Working of Laser beam machining process. Its one kind of non traditional or advanced manufacturing process.Production of laser beam and with the use of lasers how can material can be removed is to be explained over here...
LASER BEAM MACHINING - NON TRADITIONAL MACHININGSajal Tiwari
Laser Beam Machining or more broadly laser material processing deals with machining and material processing like heat treatment, allowing, cladding, sheet metal bending etc. Such processing is carried out utilizing the energy of coherent photons or laser beam, which is mostly converted into thermal energy upon interaction with most of the materials. Nowadays, the laser is also finding application in regenerative machining or rapid prototyping as in processes like stereolithography, selective laser sintering etc. Laser stands for light amplification by stimulated emission of radiation. The underline working principle of a laser was first put forward by Albert Einstein in
1917 through the first industrial laser for experimentation was developed around the 1960s. The laser beam can very easily be focused using optical lenses as their wavelength ranges from half a micron to around 70 microns. The focused laser beam as indicated earlier can have power density in excess of 1 MW/mm2 . As laser interacts with the material, the energy of the photon are absorbed by the work material leading to a rapid substantial rise in local temperature. This, in turn, results in melting and vaporization of the work material and finally material removal.
Working of Laser beam machining process. Its one kind of non traditional or advanced manufacturing process.Production of laser beam and with the use of lasers how can material can be removed is to be explained over here...
LASER BEAM MACHINING - NON TRADITIONAL MACHININGSajal Tiwari
Laser Beam Machining or more broadly laser material processing deals with machining and material processing like heat treatment, allowing, cladding, sheet metal bending etc. Such processing is carried out utilizing the energy of coherent photons or laser beam, which is mostly converted into thermal energy upon interaction with most of the materials. Nowadays, the laser is also finding application in regenerative machining or rapid prototyping as in processes like stereolithography, selective laser sintering etc. Laser stands for light amplification by stimulated emission of radiation. The underline working principle of a laser was first put forward by Albert Einstein in
1917 through the first industrial laser for experimentation was developed around the 1960s. The laser beam can very easily be focused using optical lenses as their wavelength ranges from half a micron to around 70 microns. The focused laser beam as indicated earlier can have power density in excess of 1 MW/mm2 . As laser interacts with the material, the energy of the photon are absorbed by the work material leading to a rapid substantial rise in local temperature. This, in turn, results in melting and vaporization of the work material and finally material removal.
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
There are three main types of lasers used in laser cutting.
The CO2 Laser is suited for cutting, boring, and engraving.
The neodymium(Nd) and neodymium yttrium- aluminum-garnet (NA-YAG) lasers are identical in style and differ only in application
Nd is used for boring and where high energy but low repetition are required.
The Nd-YAG laser is used where very high power is needed and for boring and engraving.
Both CO2 and Nd/ Nd-YAG lasers can be used for welding.
There are three main types of lasers used in laser cutting.
The CO2 Laser is suited for cutting, boring, and engraving.
The neodymium(Nd) and neodymium yttrium- aluminum-garnet (NA-YAG) lasers are identical in style and differ only in application
Nd is used for boring and where high energy but low repetition are required.
The Nd-YAG laser is used where very high power is needed and for boring and engraving.
Both CO2 and Nd/ Nd-YAG lasers can be used for welding.
WHAT IS LASER ???
LASER stands for Light Amplification by Stimulated Emission of Radiation.
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation
DEFINE LBM ?
LBM is a nonconventional machining process using then thermal energy of the laser beams. During the machining process, a high-energy laser beam falls on the workpiece surface and removes the workpiece material by heating, melting, and vaporizing.
LBM is a nonconventional machining process using then thermal energy of the laser beams. During the machining process, a high-energy laser beam falls on the workpiece surface and removes the workpiece material by heating, melting, and vaporizing.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Immunizing Image Classifiers Against Localized Adversary Attacks
Laser beam machining
1. Laser Beam Machining (LBM)
Principle of Laser Beam Machining (LBM)
Laser beam machining is a process in which the workpiece material is melted and
vaporized by means of an intense, monochromatic beam of light. The laser is a device,
which produces a light beam with various characteristics. Albert Einstein first published the
key principle behind the operation of the laser, when the hypothesized that, under the proper
conditions, light energy of a particular frequency could be used to stimulate the electrons in
an atom to emit additional light with exactly the same characteristics as the original
stimulating light source.
The light emitted from a laser differs from all other natural and manmade light
sources and is able to perform material processing tasks because of its properties of
monochromaticity.
Need for Laser Beam Machining (LBM)
Machining of very thin material like those used in electronic and hydraulic
components is very difficult by traditional methods. Also, few of the non-traditional methods
are not suitable in these cases. Laser beam machining (LBM) is preferred to perform micro
machining on all difficult to cut materials like ceramic, diamond, glass, semiconductor wafers
and chips etc.
Construction of Laser Beam Machining (LBM)
Laser Beam Machining equipment consists of the following main parts.
1. Ruby crystal
The cylindrical shaped ruby crystal forms the important part of the laser beam
equipment. Ruby is aluminum oxide with chromium dispersed throughout it. Both the ends of
the ruby crystal are made absolutely parallel to each other. One of the end face of the crystal
is highly silvered, so that is reflects nearly 96 % of the incident light. In order to tap the laser
output, the other end face of the crystal is partially silvered and contains a small hole through
which the laser beam emerges.
2. Xenon flash tube
The ruby crystal is surrounded by a helical flash tube containing inert gas xenon,
which itself in turn is surrounded by a reflector, to maximize the intensity of the incident light
on the ruby crystal. The flash tube is connected to a pulsed high voltage source by which the
xenon transforms the electrical energy into light energy.
3. Cooling system
A cooling system, which utilizes water, air or liquid nitrogen, is provided to protect the
ruby crystal from the enormous amount of heat generated.
2. 4. Focusing lens
The light beam or laser beam, which escapes through the tiny hole of the ruby crystal
posses low power densities. The beam is useless for material processing applications until
its power density is increased. This is achieved by means of a focusing lens. The lens
focuses the laser beam to converge to a narrow spot thereby increasing its power density.
Working Principle of Laser Beam Machining (LBM)
In operation, when the xenon flash tube is connected to a pulsed high voltage
source, the inert gas xenon transforms the electrical energy into light energy. Since the ruby
crystal is exposed to the intense light flashes, the chromium atoms of the crystal are excited
and pumped to a high energy level. These chromium atoms immediately drop to an
intermediate energy level with the evolution of heat and eventually drop back to their original
state with the evolution of a discrete quantity of radiation in the form of red fluorescent light.
As the red light emitted by one excited atom hits another excited atom, the second
atom gives off red light, which is in phase with the colliding red light wave. The effect is
enhanced as the silvered ends of the ruby crystal cause the red light to reflect back and forth
along the length of the crystal. The chain reaction collisions between the red light wave and
the chromium atoms becomes so numerous that, finally the total energy bursts and escapes
through the tiny hole as a laser beam.
The beam is focused with a simple lens to obtain high power densities in small areas
of the work surface. The intense heat of the laser beam is used to melt and, or evaporate the
workpiece material being cut. A stream of gas, like oxygen, nitrogen or argon is often used to
blow the molten metal through the cut, cool the workpiece and minimize the heat affected
zone. The type of gas used depends on the workpiece material being cut. Oxygen is used
for mild steel work pieces nitrogen or oxygen for stainless steel, nitrogen for aluminum, and
inert gas like argon for titanium metals.
3. Advantages of Laser Beam Machining (LBM) Process
_ Tool wear and breakage are not encountered.
_ Holes can be located accurately by using an optical laser system for alignment.
_ Very small holes with a large aspect ratio can be produced.
_ A wide variety of hard and difficult-to-machine materials can be tackled.
_ Machining is extremely rapid and the setup times are economical.
_ Holes can be drilled at difficult entrance angles (10° to the surface).
_ Because of its flexibility, the process can be automated easily such as the on-the-fly
operation for thin gauge material, which requires one shot to produce a hole.
_ The operating cost is low.
1.Any material, including non-metals, and irrespective of their hardness and brittleness can
be machined by laser.
2.Apart from cutting, drilling and welding materials, lasers can also be used for marking,
scribing, heat-treating of surfaces and selectively clad materials.
3.Laser Beam machining process can be easily automated.
Disadvantages of Laser Beam Machining (LBM) Process
1.Laser beam machining is costlier.
2.Low thermal efficiency.
3.Low metal removal rates.
Tapers are normally encountered in the direct drilling of holes.
The thickness of the material that can be laser drilled is restricted to 50 mm.
4.Process is limited to thin parts.
5.High reflectivity material are difficult to machine.
6.Difficult to drill exact round holes.
7.Not applicable to blind machining of metals.
Applications of Laser Beam Machining (LBM)
Laser beam machining is used to perform precision micro-machining on all materials
such as steel, ceramic, glass, diamond, graphite etc. It is used for cutting, drilling, welding of
materials, marking, scribing, heat treating of surfaces and selectively clad materials.