This document discusses various processes for working with steel, including cold rolling, annealing, forming, drawing, and joining. Cold rolling increases the strength of steel by introducing dislocations but reduces ductility. Annealing is then used to recover ductility by allowing dislocations to rearrange at high temperatures. Steel can be formed through bending, stretching, drawing, coining, and ironing. Small diameter wire is made by repeatedly drawing and annealing rod steel. Joining is done through welding, brazing, or soldering to form a metallurgical bond between pieces. Precautions like fluxes and shields are needed to prevent oxidation during high-temperature joining.
The document discusses the process of producing steel from iron ore and scrap metal. It begins with extracting iron oxide from taconite ore and refining it into pig iron in a blast furnace. Scrap metal is also a valuable source of iron. The pig iron and scrap metal are then combined and refined in a basic oxygen furnace to produce steel. Finally, the steel is continuously cast into blocks and shapes for use in various applications.
The document discusses the process of producing steel from iron ore and scrap metal. It begins with extracting iron oxide from taconite ore and refining it into pig iron in a blast furnace. Scrap metal is also a valuable source of iron. The pig iron and scrap metal are then combined and refined in a basic oxygen furnace to produce steel. Finally, the steel is continuously cast into blocks and shapes for use in various applications.
MySQL Shell/AdminAPI - MySQL Architectures Made Easy For All!Miguel Araújo
Talk given at MySQL Belgian Days 2024.
Covers all the MySQL Architectures supported to ensure business continuity with a focus on business requirements, tecnicalities, and features: InnoDB Cluster, InnoDB ClusterSet, InnoDB Cluster Read Replicas and InnoDB ReplicaSet.
A special focus is given on the AdminAPI of MySQL Shell, with its main features, recommendations, and the latest additions and features.
The document discusses Confluence and how it compares to SharePoint. It notes that Confluence is used by 83% of Fortune 500 companies, has over 190 employees, and a marketplace of 164,000 apps. In contrast to SharePoint, Confluence provides cloud-based documentation collaboration that integrates with tools like Jira and has options for on-premise or cloud-hosted deployments.
This document provides an overview of the production of cast iron. It discusses the different types of cast iron including gray, ductile, white, malleable, and compacted graphite iron. It describes the basic production process which involves melting scrap iron and steel, controlling the carbon and silicon content, pouring the liquid metal into molds, allowing it to solidify, and then removing the casting. Key factors that determine the microstructure and properties of cast iron such as composition, pouring temperature, and cooling rate are also examined. The roles of inoculants, furnaces, ladles, and molds in the production process are summarized.
This document discusses various methods for producing steel products, including casting, forging, extrusion, and powder metallurgy. It provides details on the casting process, including melting steel, transporting it in ladles, molding techniques, and addressing issues like misruns and porosity. Forging is described as shaping metal through plastic deformation using hammers or presses. The document outlines the forging process and notes that forgings have very high toughness and desirable grain flow. Extrusion and powder metallurgy techniques are also briefly mentioned.
MySQL Shell/AdminAPI - MySQL Architectures Made Easy For All!Miguel Araújo
Talk given at MySQL Belgian Days 2024.
Covers all the MySQL Architectures supported to ensure business continuity with a focus on business requirements, tecnicalities, and features: InnoDB Cluster, InnoDB ClusterSet, InnoDB Cluster Read Replicas and InnoDB ReplicaSet.
A special focus is given on the AdminAPI of MySQL Shell, with its main features, recommendations, and the latest additions and features.
The document discusses Confluence and how it compares to SharePoint. It notes that Confluence is used by 83% of Fortune 500 companies, has over 190 employees, and a marketplace of 164,000 apps. In contrast to SharePoint, Confluence provides cloud-based documentation collaboration that integrates with tools like Jira and has options for on-premise or cloud-hosted deployments.
This document provides an overview of the production of cast iron. It discusses the different types of cast iron including gray, ductile, white, malleable, and compacted graphite iron. It describes the basic production process which involves melting scrap iron and steel, controlling the carbon and silicon content, pouring the liquid metal into molds, allowing it to solidify, and then removing the casting. Key factors that determine the microstructure and properties of cast iron such as composition, pouring temperature, and cooling rate are also examined. The roles of inoculants, furnaces, ladles, and molds in the production process are summarized.
This document discusses various methods for producing steel products, including casting, forging, extrusion, and powder metallurgy. It provides details on the casting process, including melting steel, transporting it in ladles, molding techniques, and addressing issues like misruns and porosity. Forging is described as shaping metal through plastic deformation using hammers or presses. The document outlines the forging process and notes that forgings have very high toughness and desirable grain flow. Extrusion and powder metallurgy techniques are also briefly mentioned.
This document discusses various methods of surface hardening steel, including flame hardening, induction hardening, laser hardening, carburizing, nitriding, and boriding. It explains how each process works to intensify the surface of steel parts in order to increase hardness and wear resistance while leaving the interior softer. Precise control and monitoring of the temperature and time parameters are emphasized as important for achieving the desired case depth and microstructure in the hardened surface.
The document discusses heat treating large or heavy steel parts. It explains that large parts cannot be heated or cooled uniformly like small parts due to their size. Only the outer layers of heavy parts can fully transform to martensite during quenching. Alloy additions are needed to achieve high strength throughout large parts. The document also covers continuous cooling transformation diagrams, effects of alloying elements, and considerations for heat treating specialty alloy steels.
The document discusses the production and properties of aluminum alloys. It describes how aluminum is extracted from bauxite ore through the Bayer process, then refined using electrolysis. Aluminum can also be produced from recycled scrap, which saves energy. The properties and applications of common aluminum alloys are covered. Production methods for aluminum include casting, rolling, extruding, forging, and powder metallurgy. Safety considerations are discussed for working with aluminum powder.
The document discusses metallurgy and how understanding metallurgy can help solve problems in metal production and applications. It defines key terms like ferrous metals, microstructure, and processes. It provides examples of how understanding composition, microstructure, and properties allowed engineers to solve issues like warped lawnmower blades, a tractor axle shaft breaking, and fractured lock washers. The document emphasizes that knowledge of metallurgy is useful for many metal-related jobs and industries.
The document discusses heat treating steels through various heating and cooling processes to achieve desired material properties. It describes heating steel to form austenite, then cooling through different rates to form different microstructures like pearlite or martensite. Rapid cooling through quenching produces martensite for high strength. Various quenching mediums like water, brine, and oil are discussed. The effects of alloying elements and proper furnace atmospheres on the heat treating process are also summarized.
This document discusses the production and applications of various metals, including zinc, tin, lead, mercury, and depleted uranium. It describes how zinc is extracted from ore through roasting or leaching processes. Zinc is commonly used in die casting to produce parts for applications requiring creep resistance at elevated temperatures, such as engine components. Tin is extracted from the mineral cassiterite and is primarily used in solders, especially tin-lead solders used in electronics manufacturing due to their low melting point. Printed circuit boards require solder joints with very high success rates due to their small scale and tight tolerances.
The document discusses various topics relating to the physical and chemical properties of metals, including:
- How the microstructure of metals is influenced by factors like composition, deformation, and heat treatment.
- How processes like casting, hot working, cold working, and annealing impact the grain structure and properties of metals.
- Common physical properties of metals like density, thermal expansion, electrical and magnetic conductivity.
- How properties like strength, ductility, and machinability are influenced by a metal's microstructure.
This document discusses various bulk deformation techniques including forging, rolling, and extrusion. It covers topics like hot working versus cold working, the advantages of each, and specific forging processes like closed-die forging. Forging refines grain structure and improves properties. It describes how grain flow follows the deformation pattern. The document also discusses forging equipment, defects, and provides examples of forging a connecting rod and crankshaft.
The document discusses phase diagrams and how they relate to the microstructure and properties of steels. It explains that phase diagrams show the different phases that exist at various temperatures and compositions for materials like iron-carbon alloys. The diagrams are used to understand how cooling rates affect the microstructure of steels and allow engineers to develop steels with desired properties by controlling the processing conditions.
This document provides an overview of forging processes and principles. It discusses various forging operations like smith forging, hammer forging, press forging, and roll forging. It also covers forging classification based on temperature (hot, warm, cold forging) and die arrangement (open, closed die forging). Common forging defects and applications in industries like automotive and aerospace are summarized.
This document discusses three light metals: magnesium, beryllium, and lithium. It describes their properties, extraction and processing methods, common applications, and safety precautions when working with each metal. Magnesium is extracted via electrolysis and commonly cast or die cast. Beryllium is a rigid metal used in mirrors and electronics and poses health risks if dust is inhaled. Lithium is the least dense metal, extracted from salt brines, and used in batteries due to its electrochemical properties though it is highly reactive.
The document summarizes the rolling process. It defines rolling as plastically deforming metal by passing it between rolls. Rolling provides close dimensional control and high production. There are two main types: hot rolling and cold rolling. The document describes various rolling terminologies, mill products, defects, and different rolling processes like hot rolling, cold rolling, shaped rolling, and thread rolling. It also discusses factors like angle of contact, forces involved, and how to control flatness.
The document discusses the rolling process for metal forming. Rolling is defined as passing metal between rolls to plastically deform it. There are two main types: hot rolling, which is used for initial breakdown of ingots, and cold rolling, which provides closer dimensional tolerances and better surface finishes. Rolling can produce products like plate, sheet, strip, bars, and pipes. The rolling process involves passing metal through sets of rolls under high compressive forces.
Metal rolling is one of the most important metal forming processes. It involves plastically deforming metal between two rolls to reduce thickness and shape the metal. Most metals are hot rolled into basic shapes like blooms and slabs for further manufacturing. The rolls spin in opposite directions to feed and form the metal through compression. Friction must be controlled through lubrication. Rolling refines grain structure and spreads the width of the metal. Different roll materials, sizes, and mill configurations are used depending on the application. Surface defects can occur if scale or dirt are present while internal defects result from improper material distribution.
1. Cold working is the plastic deformation of metals at a temperature below the recrystallization temperature, while hot working occurs above the recrystallization temperature.
2. Metal spinning is a metalworking process that forms an axially symmetric part by rotating a disc or tube of metal at high speed against a spinning roller. It can be done by hand or CNC lathe.
3. Forging processes like upsetting, heading, blocking, and fullering are used to refine the shape of metals for finishing. Punching and blanking are shearing processes used to produce holes.
This document discusses the machinability of various tool steels. It provides information on different types of tool steels classified by the AISI and how their machinability is influenced by factors like composition, microstructure, and heat treatment. Machining operations like turning, drilling, milling, and face milling of tool steels are also covered, outlining tool materials, speeds/feeds, cutting fluids, and heat treatments used for optimal machinability. Tool steels require special machining techniques due to their high hardness, carbon content, and alloying elements.
The document discusses various aspects of extrusion, a manufacturing process where a block of metal is forced to flow through a die opening. It describes different types of extrusion like hot and cold, direct and indirect, lubricated and hydrostatic. It also discusses defects in extrusion and the drawing process which is similar but uses a pulling force. The key information provided includes how extrusion allows shaping of solid and hollow metal sections, the operating principles and classifications of extrusion, and factors that affect the extrusion force.
The document discusses the extrusion manufacturing process. Extrusion involves forcing a block of metal through a die to create solid or hollow shapes. There are different types of extrusion classified by direction (direct, indirect), operating temperature (hot, cold), and equipment (horizontal, vertical). Hot extrusion is done at high temperatures using lubrication while cold extrusion is done at room temperature. The document also discusses defects, drawing as a related process, and factors that affect extrusion forces.
The document discusses the drivers and pressures for organizational change. It identifies that change comes from both external environmental pressures such as competition, regulations and technological changes as well as internal pressures like growth, leadership changes, and politics. Some of the key external pressures mentioned are globalization, hypercompetition, and reputation concerns. The document also examines why organizations may not change in response to environmental pressures or after crises, citing factors such as organizational learning difficulties and defensive priorities over innovation.
This document discusses evolutionary developmental biology and how changes in development can lead to evolutionary changes. It provides examples of modularity and molecular parsimony which help explain this. Modularity means parts of the body and DNA can develop differently. Molecular parsimony means organisms share developmental toolkit genes. The document then discusses specific examples like stickleback fish pelvic spines being due to different Pitx1 expression, and Darwin's finches having beak shape variations due to differing Bmp4 and Calmodulin expression levels. Mechanisms of evolutionary change include changes in location, timing, amount, or kind of gene expression.
Developmental plasticity allows an organism's phenotype to change in response to environmental conditions during development. There are two main types of phenotypic plasticity: reaction norms, where the environment determines the phenotype from a continuum of genetic possibilities, and polyphenisms, where discrete alternative phenotypes are produced. Examples include caterpillars changing appearance to match plant growth stages, frogs hatching early in response to vibrations, and temperature determining sex in crocodiles. Stressors like water levels can also influence development, as seen in spadefoot toads. Symbiotic relationships between organisms, like nitrogen-fixing bacteria in plant roots, are important to development and often involve vertical transmission from parents. Gut bacteria are also necessary for
This document discusses several genetic and environmental factors that can influence human development. Genetic factors like pleiotropy and mosaicism can result in syndromes with multiple abnormalities. The same genetic mutation can also produce different phenotypes depending on gene interactions. Environmental teratogens during critical periods of embryonic development can irreversibly damage organ formation, with alcohol, retinoic acid, and endocrine disruptors like bisphenol A and atrazine posing particular risks like fetal alcohol syndrome, cleft palate, lower sperm counts, and cancer. Both genetic and environmental heterogeneity contribute to the complexity of human development.
The endoderm forms the epithelial lining of the digestive and respiratory systems. It gives rise to tissues like the notochord, heart, blood vessels, and parts of the mesoderm. The endoderm comes from two sources - the definitive endoderm and the visceral endoderm. The transcription factor Sox17 marks and regulates the formation of the endoderm. The endoderm lines tubes in the body and gives rise to organs like the liver, pancreas, lungs and digestive system through the formation of buds and pouches along the foregut.
The document summarizes the development of the intermediate mesoderm and lateral plate mesoderm. The intermediate mesoderm forms the urogenital system including the kidneys, ureters, ovaries, fallopian tubes, testes and vas deferens. Kidney development occurs through the pronephros, mesonephros and metanephros stages. The lateral plate mesoderm splits into somatic and splanchnic layers and forms the heart through the merging of cardiac progenitor cells from both sides of the embryo. The heart tube loops to the right to begin resembling the four-chambered adult heart.
The paraxial mesoderm lies just lateral to the notochord and gives rise to vertebrae, skeletal muscles, and skin connective tissue. It is divided into somites which then form dermomyotomes and sclerotomes. Dermomyotomes develop into dermatomes that make dermis and myotomes that form back, rib, and body wall muscles. Sclerotomes form the vertebrae and rib cage. Somitogenesis occurs through a clock-wavefront model where somites sequentially segment from cranial to caudal regions under the influence of signaling molecules like retinoic acid and FGF.
The document summarizes ectodermal placodes and the epidermis. It discusses how placodes give rise to sensory structures like the eye lens, inner ear, and nose. It describes the different cranial placodes that form sensory tissues and nerves, including the anterior placodes that form the pituitary gland and eye lens. The intermediate placodes form nerves involved in sensation of the face and hearing/balance. The epidermis derives from surface ectoderm under the influence of BMPs and forms the protective outer layer of skin and its appendages like hair, sweat glands, and teeth.
- The neural plate transforms into a neural tube through a process called neurulation regulated by proteins like BMP and transcription factors like Sox1, 2, and 3.
- Primary neurulation involves the elongation, bending, and convergence of the neural folds before their closure at the midline to form the neural tube. Key regulation events involve hinge points at the midline and dorsolateral edges.
- Neural tube defects can occur if closure fails, as in spina bifida where the posterior neuropore remains open, preventing proper spinal cord development.
Mammalian development begins with fertilization and cleavage of the egg. The egg develops membranes that allow development outside of water. In mammals, the placenta exchanges gases and nutrients between the embryo and mother. Cleavage is rotational, with zygotic genes activating later than other animals. Cells compact and the morula forms an inner cell mass and trophoblast cells. The trophoblast secretes fluid to form a blastocyst cavity. The inner cell mass forms the epiblast and hypoblast, which generate the embryo and extraembryonic tissues through gastrulation. Axis formation is guided by gradients of genes like HOX and left/right asymmetries are regulated by proteins including Nodal.
- Drosophila melanogaster is a useful model organism for studying development due to its short life cycle, fully sequenced genome, and ease of breeding.
- Early Drosophila development involves syncytial cleavage where nuclei divide without cell division, specifying the dorsal/ventral and anterior/posterior axes.
- Fertilization occurs when sperm enters an egg that has already begun specifying axes; maternal and paternal chromosomes remain separate during early divisions.
This document summarizes key patterns in animal development. It describes that animals undergo gastrulation where cells migrate to form germ layers and axes. Animals are categorized into 35 phyla based on features like germ layers, organ formation, and cleavage patterns. It describes that diploblastic animals have two germ layers while most are triploblastic with three germ layers. Triploblastic animals are further divided into protostomes and deuterostomes based on mouth formation. The document also provides examples of cleavage patterns in snails which are spirally arranged in either a dextral or sinistral pattern determined by maternal factors.
1) Sex determination in mammals is primarily determined by the XY sex determination system, with females having XX and males having XY. The SRY gene on the Y chromosome causes the development of testes.
2) The gonads are initially bipotential but develop into either ovaries or testes based on the sex chromosomes. Testes secrete AMH and testosterone to direct male development while ovaries secrete estrogens for female development.
3) Gametogenesis includes the process of meiosis which produces haploid gametes from diploid germ cells in the gonads. In females, oogenesis begins in the embryo but arrests until puberty while spermatogenesis only occurs at puberty in males.
Stem cells are unspecialized cells that can divide and differentiate into specialized cell types. There are several types of stem cells defined by their potency, including totipotent stem cells found in early embryos, pluripotent stem cells in the embryo, and multipotent adult stem cells. Stem cell regulation is controlled through extracellular signals from the stem cell niche and intracellular factors that influence gene expression and cell fate. Researchers have also induced pluripotency in adult cells by introducing genes that code for key transcription factors.
This document discusses cell-to-cell communication and how it allows for the development of specialized tissues and organs through three main mechanisms: cell adhering, cell shape changing, and cell signaling. It describes how cells interact at the cell membrane through various receptor and ligand proteins. These interactions can be homophilic or heterophilic, and occur through direct contact between neighboring cells (juxtacrine signaling) or over short distances (paracrine signaling). Differential adhesion and cadherins allow cells to sort themselves into tissues based on adhesion strengths. The extracellular matrix and integrins also influence cell communication and development.
Differential gene expression refers to the process where different genes are activated in different cell types, leading to cellular specialization. While all cells contain the full genome, only a small percentage of genes are expressed in each cell. Gene expression is regulated at multiple levels, including differential transcription, selective pre-mRNA processing, selective mRNA translation, and posttranslational protein modification. The most common mechanisms involve regulating transcription through epigenetic modifications of chromatin and the use of transcription factors.
The document summarizes key stages in animal development from fertilization through organogenesis. It begins with fertilization and cleavage, followed by gastrulation where the three germ layers (endoderm, mesoderm, ectoderm) are formed. During organogenesis, organs develop from the germ layers. Metamorphosis may also occur to transition organisms like frogs from immature to sexually mature forms. Examples are provided of developmental processes in frogs and other model organisms like fruit flies and plants. Cell behavior and patterning during these stages are also discussed.
The document discusses considerations for small businesses when hiring employees. It covers deciding when to hire an employee, defining job roles, writing job descriptions, attracting and evaluating candidates, selecting the right hire, training employees, rewarding and compensating employees, and managing ownership and dividends when there are family business partners involved. The key aspects of setting up an employee program for a small business are planning job roles, writing thorough job descriptions, developing fair hiring and review processes, providing training, and establishing clear compensation and ownership structures.
This document discusses various legal issues that small business owners should be aware of, including:
- Understanding the different types of laws (federal, state, local) that may apply to a small business.
- Hiring an experienced small business attorney to provide legal advice and represent the business as needed.
- Choosing an appropriate legal structure for the business, such as a sole proprietorship, partnership, corporation, or LLC.
- Protecting the business name as intellectual property and complying with regulations regarding contracts, liability, taxation and other legal matters.
This document discusses risk management and insurance for small businesses. It begins by defining risk for business owners and identifying common sources of risk such as financial investments, theft, nonpayment of debts, and natural disasters. It then examines risks related to a business's property, personnel, customers, and intangible property. The document provides strategies for managing these risks, such as developing policies and procedures, securing valuable assets, and obtaining different types of insurance. It concludes by discussing ways for businesses to share risk through joint ventures, industry groups, and government funding programs.
This presentation was provided by Rebecca Benner, Ph.D., of the American Society of Anesthesiologists, for the second session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session Two: 'Expanding Pathways to Publishing Careers,' was held June 13, 2024.
A Visual Guide to 1 Samuel | A Tale of Two HeartsSteve Thomason
These slides walk through the story of 1 Samuel. Samuel is the last judge of Israel. The people reject God and want a king. Saul is anointed as the first king, but he is not a good king. David, the shepherd boy is anointed and Saul is envious of him. David shows honor while Saul continues to self destruct.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
3. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Describe the effects of cold-rolling on steel strip, at both the microscopic
and macroscopic scales.
• Explain the effects of annealing on cold-worked steel, at both the
microscopic and macroscopic scales.
• Understand the differences between drawing and stretching steel sheet.
• Understand why steel wire must be drawn multiple times to make small-
diameter wire.
• Understand what a metallurgical bond is.
Learning Objectives
4. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• State the three things necessary to form a metallurgical bond.
• Describe the major advantage of brazing over welding steel.
• Understand why free-machining steels are easier to cut than other
steel alloys.
• Explain why galvanizing steel protects the steel better than tinplate.
• List three ways to protect steel sheet from corrosion due to moisture
in the air.
Learning Objectives
5. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• As metal is reduced in thickness, cold work increases.
• Dislocations in metal allow atoms to slide past one another.
• Metal changes shape without fracturing.
• Dislocation tangles develop.
• Strength increases.
• Elongation is reduced.
Cold-Working Steel
6. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Steel is not hot-rolled under 3/16″ (4.8 mm)
thickness.
• Too much rough oxide scale at hot-rolling
temperatures
• Thinner gages are made by cleaning hot
strip, then cold-rolling at room temperature.
Cold-Rolled Sheet and Strip
Goodheart-Willcox Publisher
7. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Steel for cold-rolling is etched in acid (pickled).
• Uncoiled and fed through acid tanks to remove scale
• Washed, dried, and recoiled for cold-rolling
• Iron oxide scale is returned for smelting.
Cold-Rolled Sheet and Strip (cont.)
8. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Cold-rolling is typically done in four-high
rolling mills.
• Operators adjust process to achieve
desired reduction.
• Roll reduction, rolling speed, and tension
are controlled.
• Each roll reduction is a single pass
through rolls.
Controlling Thickness
JETSADA POSRI/Shutterstock.com
9. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Noncontact X-ray gauges measure gage thickness.
• Front (nose) or end (tail) of coil may be outside specified thickness.
• Must be cut off and recycled (mill scrap)
Controlling Thickness—Noncontact X-ray
Gauges
10. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Thickness variation across width is cause for rejection.
• Drawing and forming dies for next step function within narrow range of
thicknesses.
• Mill operators learn to make uniform reductions across width of
strip.
• Minimizes scrap
Importance of Uniform Thickness
11. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• As strip is cold-rolled, force needed to cold work increases.
• Ductility decreases.
• Small edge cracks can form.
• Cracks must be trimmed before further rolling.
• Strip with cracked edges cannot be shipped to customers.
• Trimmed edges become mill scrap.
Work Hardening
12. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Annealing is used to recover ductility in cold-rolled strip.
• Steel may be process annealed partway between initial gage and
final thickness.
• Usually heated to 1200°F (650°C) or above
• Then air-cooled
• Finally ready to roll to thinner gage
• Resulting microstructure is equiaxed ferrite and pearlite.
Annealing
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• Advantage of 1200°F–1300°F (650°C–700°C) process anneal is
simplicity.
• Uses less complex ovens than for higher temperatures
• Disadvantage is longer time required.
• Process is slower at lower temperatures.
• Can take 15 to 24 hours
Lower-Temperature Process Anneal
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• Advantage of 1400°F–1600°F (760°C–870°C) process anneal is
speed.
• Only one hour in furnace
• Requires expensive ovens for higher temperatures
• Higher energy input
• Controlled atmosphere
• Good door seals
Higher-Temperature Process Anneal
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• Uncoiled steel strip can be annealed in a continuous furnace.
• Steel strip is rapidly heated to over 1400°F (760°C).
• Held at temperature for less than one minute
• Cooled back to room temperature
• Protected by nitrogen-hydrogen atmosphere during annealing
Continuous Furnace Annealing
Goodheart-Willcox Publisher
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• Stationary (coil) and continuous (strip) annealing furnace
differences
• Different requirements for operators
• Produce slightly different metallurgical results
• Batch annealing (in coils) produces larger grain size.
• Produces rougher surface after cold forming
• Applications use formed areas not visible to customer.
Stationary vs. Continuous Anneal
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• Continuous strip steel annealing
produces smaller grain size.
• Sheet bends more uniformly.
• Has smoother and cleaner
surface
• Less preparation needed for
painting
Stationary vs. Continuous Anneal (cont.)
Goodheart-Willcox Publisher
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• Cold-rolled strip
• Shipped as fully or partly cold-worked
and annealed
• May be cut into flat sheet or coiled
• Based on annealing temperature and
time
• Different yield strength
• Different elongation
Semifinished Sheet and Strip
PhotoStock10/Shutterstock.com
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• Several things may be specified by
customer.
• Processing and annealing conditions
• Edge condition
• Maximum weight of each coil
• Direction of coil core
• Steel strapping requires high strength but
low formability.
• Shipped in fully cold-worked condition
Cold-Rolled Steel Requirements
Zygalski Krzysztof/Shutterstock.com
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• Strip and sheet applications involve
forming operations.
• Bending, stretching, drawing, coining,
or ironing
• Bending stresses below elastic limit will
not permanently change shape.
• Returns to original shape when stress
removed
Forming Sheet by Bending
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• Bending stresses at levels above elastic limit cause permanent
change in shape.
• Sheet will return partway to original shape.
• Effect is called springback.
Springback
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• Press brake machines bend sheet and plate.
• Setup must overbend slightly to allow for
springback.
• Springback is sensitive to variations in cold
work and annealing.
• May need to adjust press for each coil
• Sheet metal cracks if bent too far.
• Steel supplier provides tables showing
minimum bend radius.
Press Brake
Dmitry Kalinovsky/Shutterstock.com
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• Stretching sheet increases surface area and reduces thickness.
• Example of coil cut into 8′ (2.4 m) lengths for flat sheet
• Sheet is stretched between two grips.
• Makes sheet very flat and puts set into it
• It is fixed in that state.
• Flat steel workpieces may be stretched in die to form useful parts.
Forming Sheet by Stretching
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• Flat sheet is drawn (pulled) into die cavity.
• No change in thickness
• Common application is home appliances.
• Called “white goods” regardless of painted
color
• Sides and tops made from thin cold-rolled
annealed strip
• Scratches caused by worn forming tools
appear through paint.
• Causes customer rejection
Forming Sheet by Drawing
Goodheart-Willcox Publisher
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• Stretcher-strain marks are caused by forming.
• Cannot be removed
• Appear through paint
• Unacceptable for white goods
• Root cause occurs at atomic level.
• When metal is loaded to upper yield stress,
some dislocations break free.
• Forms marks as pinned dislocations move
Stretcher-Strain Marks
Goodheart-Willcox Publisher
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• Mild cold work moves dislocations that cause problem.
• Skin pass (temper roll) of sheet can reduce thickness about 2%.
• Bending sheet slightly through series of small rollers in roller leveling
pass brings no thickness change.
• Steel must be used quickly.
• Within about two weeks at room temperature
Preventing Stretcher-Strain Marks
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• Thickness of flat workpieces can be changed by coining.
• Coining stamps a punch onto flat sheet.
• Back plate holds sheet in place.
• Impression of punch is permanent.
Forming Sheet by Coining
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• Thickness of sheet can be reduced by ironing.
• Sheet is drawn through wedge-shaped ironing
die.
• Compresses and thins it as it is pulled through
• Beverage cans use this method.
• Requires very clean steel
• Uses special lubricants
Forming Sheet by Ironing
Goodheart-Willcox Publisher
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• Small-diameter wire is cold-drawn from hot-rolled coiled rod.
• Steel wire must be drawn multiple times to create small-diameter
wire.
Drawn Wire
Goodheart-Willcox Publisher
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• Frequently annealed between draws
• Reduces cold work and drawing force required
• Drawing dies for larger diameters are made of hard materials.
• Tungsten carbide
• Diamond for very small diameters
Drawn Wire (cont.)
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• Springs undergo many fatigue cycles.
• Every time they are compressed and
released.
• Many springs must withstand millions of
cycles without failure.
• Small surface notches act as stress
risers.
• Technicians must be alert to avoid this.
Drawn Wire for Small Springs
Julian Rovagnati/Shutterstock.com
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• For drawing tube, starting material is
extruded tube.
• Tube is drawn through a reducing die.
• An inside plug assures desired inside
diameter and finish.
Drawn Tube
Goodheart-Willcox Publisher
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• Room-temperature forging is called cold forging.
• Cold work develops dislocation tangles.
• Strength increases, and amount of deformation
is restricted.
• Metal is often forced into closed dies.
• Workpiece is kept under compressive load to
avoid cracking.
• Rod rolled between threaded rollers or plates
creates threads.
Cold Forging
Tawansak/Shutterstock.com
34. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Three ways to join pieces together
• Metallurgical bond, glue, or mechanical fasteners
• Metallurgical bond joins metals at atomic level.
• Metallurgical joining includes welding, brazing, and soldering.
• Workpieces (materials to be joined) are called parent metals.
• Metal added to joint is called filler metal.
Joining Steel Parts
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• Three requirements for metallurgical bond
• Heat to melt either parent or filler metal
• Disruption of surface oxide of all metals at joint region
• Protection from oxidation or contamination while parts are hot
• American Welding Society (AWS) offers standards and certifications for
welding.
• AWS definition of welding
• Process that melts part of parent metals so liquid forms a metallurgical bond
between pieces, with or without filler
Requirements for a Metallurgical Bond
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• Brazing and soldering do not melt parent metal.
• Form metallurgical bond between parent metals with filler metal
• AWS defines brazing as occurring above 840°F (450°C).
• Soldering occurs below 840°F (450°C).
• In all joining processes, parent metal is heated.
• Changes in parent microstructure are common.
Brazing and Soldering
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• Metals have surface oxide films that hinder metallurgical bonds.
• When oxide film is disrupted, metal atoms from both sides merge
together.
• Braze or solder fluxes help melted filler metal penetrate oxides.
• Metallurgical bond can form.
Metallurgical Bonds and Fluxes
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• Metals to be joined must be compatible.
• If joint serves structural purpose, it must not become brittle.
• Nickel can be safely welded to steel rod.
• Liquid metals mix and form sound metallurgical bond.
• Some metals cannot be joined without becoming brittle.
• Aluminum is not metallurgically compatible with steel.
• Aluminum-to-steel welds immediately form brittle compounds.
Metallurgical Bonds and Compatibility
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• Parent metals are melted in area to be joined.
• Flux or cover gas protects hot metal from oxidation.
• Flux or cover gas protects metal from atmospheric moisture.
• H2O is source of hydrogen and oxygen.
• Over 70 welding variations exist to produce combination of heat,
filler, and shielding.
Welding
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• Arc welding is most common method
of joining metals.
• Shielded metal arc welding (SMAW)
uses flux-coated electrode.
• Flux melts and shields weld area.
• Electrode (a metal wire) is filler metal.
Arc Welding: SMAW
Goodheart-Willcox Publisher
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• Gas metal arc welding (GMAW)
uses cover gas but no flux.
• Gas may be inert (argon or helium).
• Gas mixtures may be chemically
reducing.
• Without flux, there is no slag to chip
off.
Arc Welding: GMAW
Goodheart-Willcox Publisher
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• Welders must wear protective clothing and equipment.
• Cotton and leather items are preferred to synthetics.
• Welding arc produces harmful intense light.
• UV radiation damages exposed skin and permanently damages eyes.
• Opaque face shields and dark-tinted glass view ports are required.
• Plastic curtains should surround welding areas to protect anyone
nearby from UV radiation.
Safe Arc Welding
Safety Note
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• Gas tungsten arc welding (GTAW) uses cover gas (inert or
reducing).
• Uses nonconsumable tungsten electrode
• Separate filler metal may be used.
• GTAW gives welder great flexibility.
• GTAW requires more training.
Arc Welding: GTAW
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• All arc welding methods melt some parent
metal.
• Microstructure near weld is affected.
• Cast microstructure occurs near center of weld.
• HAZ is between cast structure and unaffected
base metal.
• Includes partially melted parent metal
• Recrystallized microstructures found there
• Welds can become brittle there.
Heat-Affected Zone (HAZ)
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• High-carbon steels and cast iron may become brittle.
• Welding these requires special procedures.
• Special filler alloys
• Preheating and postheating practices
• Welds may crack during cooling.
• They should be inspected before shipping.
• Nondestructive test methods are often used.
• Dye penetrant tests
• X-ray
• Ultrasonic inspection
Problems in Welding Steel
NDT Specialists, Inc.
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• Resistance welding is used to
make small tube on tube mill.
• Thin sheet is roll-formed into
tube.
• Resistance welding joins two
edges using rotating electrodes.
• Tubes can be drawn and
annealed.
Welded Small Tube
aaltair/Shutterstock.com; Reprinted with Permission from Plymouth Tube Co. (www.plymouth.com
47. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Spot welding is resistance welding small
areas between parts.
• Resistance welding uses metals’
electrical resistance for heat.
• Copper electrodes press metal pieces
together, shielding from air.
Resistance Welding
Goodheart-Willcox Publisher
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• Electrical current melts weld joint.
• Amount of current and time must be controlled carefully.
• Electrodes must be clean and dressed.
• Electrodes may only last one shift.
Resistance Welding—Electrical Current
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• Parts with cylindrical profile can be friction
welded.
• One part spins and presses against another part.
• Heat generated by friction melts both metals.
• Forcing parts together shields weld area from air.
• Drives out any liquid metal
• Some difficult-to-weld combinations can be
friction welded.
Friction Welding
Manufacturing Technology, Inc.
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• Forge bonding (forge welding) is very old process.
• Swords were made by hammering hot blooms together.
• Used multiple iron blooms with different carbon content.
• Modern forge bonding involves hot-rolling different alloys to bond
them into single piece.
• Carbon steel can be sandwiched between slabs of stainless steel
and rolled.
• Finished sheet resists corrosion like stainless steel sheet.
Forge Bonding/Welding
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• Brazing can make leak-tight joints quickly and
consistently.
• Valuable for producing fluid containers, such as
radiators
• Braze joints use filler alloy, since parent alloys
are not melted.
• Flux or controlled atmospheres are used.
Brazing
Handy & Harman/Lucas Milhaupt, Inc.
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• When filler alloy melts, it wets parent metal.
• Capillary action pulls liquid into joint area.
• Property of liquid to flow and fill spaces due to surface tension
• Creates brazed joints
• Operator must control several things.
• Amount and area of heating
• Flux and filler additions
Brazing and Capillary Action
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• Parts can be brazed in controlled-atmosphere furnace.
• No flux is needed.
• Atmosphere must be monitored frequently.
Brazing and Capillary Action (cont.)
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• Soldering joins parts without high temperatures.
• Requires suitable flux
• Solder filler wets steel and fills joints like brazing.
• Makes leak-free joints in steel pipe
• Makes permanent electrical connections
• Less strong then other weld joints
Soldering
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• Training is required to perform
processes consistently.
• Personnel must know what to
adjust and inspect.
• Welders
• Brazing technicians
• Furnace operators and
technicians
Skilled Metallurgical Bonding
Goodheart-Willcox Publisher
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• Gluing parts together with adhesives is an option for product
designers.
• Where two sheets overlap closely for 3/8″ (1 cm) or more, this
method works.
• Advantages include bonding without heat.
• Cleaning and preparation of parent surfaces is critical.
Adhesive Joining
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• Sheets can be joined mechanically with bolts, rivets, or screws.
• Heat is not needed.
• Dissimilar materials can be joined.
• Holes may be needed and can allow leakage.
• Mechanical fastener locations are stress raisers.
Mechanical Joining with Bolts
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• Steel sheets can be joined by clinching
two sheets together.
• Sheets can be clinched together in less
than a second.
• Joint does not puncture either sheet
and remains leak-free.
• Key disadvantage is visible button
formed on surface.
• Clinching is usually done in areas not
visible to user.
Mechanical Joining by Clinching
Goodheart-Willcox Publisher
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• Machining processes can make smooth, precise surface or final
shape.
• Machining, cutting, grinding, and polishing remove metal from
workpiece.
• All involve pressing sharp tool or abrasive against workpiece.
Cutting, Grinding, and Polishing
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• Tougher, stronger materials are more difficult to cut.
• ASTM International has machinability ratings for metals.
• Alloy UNS G11120 has 100% machinability rating.
• Metals with high machinability rating do not wear out cutting tools
quickly.
• They show little galling.
• Galling is wear caused by two surfaces rubbing and sticking together.
Machinability of Steel Alloys
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• Steels with sulfur or lead have improved
machinability.
• Alloys called free-machining steels
• Iron sulfide and lead globules cause chips to
break easily.
• Small machining chips produced instead of
long curls
• Limitations on use
• Should not hot-work high-sulfur steels
• Should not weld these steels
Free-Machining Steels
Iakiv Pekarskyi/Shutterstock.com
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• Grinding wheels do not cut well when clogged with soft metal.
• Grinding wheels for sharpening steel tool bits should never be used
to grind soft metals.
• Aluminum or mild steel embed in a wheel’s surface.
• Prevents wheel from grinding hardened steel tools
• Wheel must be dressed before being used again.
Care of Grinding Wheels
Practical Metallurgy
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• Parts polished to smooth, glossy finish with fine polishing grit.
• Polishing powder must not become contaminated.
• With coarser polishing powder
• With small stray metal particles (fines)
• Lapping and burnishing are different polishing procedures.
Polishing
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• Steel rusts in typical outdoor air.
• It forms iron oxide (Fe2O3).
• Iron oxide eventually flakes off and forms pits or holes.
• Three ways to reduce corrosion in steel
• Protect with coating
• Connect electrically to more electronegative metal
• Process to be less susceptible
Controlling Corrosion
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• Metal coatings can be passive or protective.
• Passive coatings protect steel only by shielding it from air.
• Protective coatings actively protect when steel becomes exposed.
Controlling Corrosion with Coatings
Goodheart-Willcox Publisher
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• Tinplate (tin-coated steel) is passive protection.
• If scratched, exposed steel can corrode.
• Nearly 1/10 of all steel produced in US is used for tinplate.
• Most ends up in food packaging.
Tinplate Coatings
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• Zinc-coated (galvanized) steel has active
protection.
• Zinc is more reactive and corrodes before steel.
• Galvanizing is usually done at end of production.
• Example: Galvanizing after joining steel parts
into structure
Zinc Coating: Galvanizing
Jay Warner
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• Steel is electroplated with corrosion-
resistant chromium.
• Provides shiny surface on steel parts
• Chrome plate for outdoor applications
uses layer of copper and nickel under
chrome.
• Improves adherence
Chrome Plate
streetphotog66/Shutterstock.com
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• Years ago, fasteners were commonly plated with cadmium.
• Cadmium metal is toxic to humans.
• Cadmium is now classified as carcinogenic by health agencies.
• Cadmium-plated parts are effectively forbidden by EU and US.
Cadmium Plate
Safety Note
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• Food containers can react with food stored in them.
• Need inner coating that does not react with food
• Various organic coatings used, depending on food
• Example: Nonacidic beans use different coating than acidic pineapple.
Organic Coatings
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• Galvanic corrosion occurs when dissimilar metals are in contact.
• Corrosion of more reactive metal protects second metal.
• Called sacrificial corrosion
Protecting Steel by Sacrificial Corrosion
Joe Mabel
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• Magnesium commonly used to protect steel parts
• Can occur in weldments due to composition variation
• Filler metal should be selected to avoid this problem.
Protecting Steel by Sacrificial Corrosion
(cont.)
73. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.
• Process variables can change corrosion resistance of parts.
• Through composition changes
• Through microstructure changes in selected areas
• Welded stainless steel is an example.
• Chromium carbides can form during cooling.
• Chromium content is lowered next to grain boundaries.
• Intergranular corrosion can occur.
Protecting Steel through Process
Variables
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• Processes discussed in this chapter create by-products (waste).
• Waste may be personally or environmentally hazardous.
• Cold-rolling and forming lubricants
• Smoke and dust from welding and brazing
• Fluxes for brazing
• Solvents for paint or organic coatings with VOCs
• Operations work to reduce negative impact.
Considering the Impact
Sustainable Metallurgy