This document provides an overview of special casting processes, including die casting, centrifugal casting, and precision casting. It discusses the key characteristics of each process, such as die casting using pressure to force molten metal into metal molds, allowing for small, complex parts to be produced in large quantities. Centrifugal casting involves rotating a mold to utilize centrifugal force to position molten metal, suitable for symmetrical shapes. Precision casting creates highly accurate castings using ceramic shell molds, enabling unmachined alloys and radioactive metals to be cast.
This document discusses various casting processes including investment casting, plaster mold casting, ceramic mold casting, permanent mold casting, and die casting. It describes the key steps in each process and notes advantages and limitations. Defects that can occur in castings such as misruns, cold shuts, and shrinkage cavities are also outlined.
The document discusses various manufacturing processes. It provides details about metal casting processes like sand casting and special casting processes such as shell mold casting and investment casting. Sand casting involves pouring molten metal into a sand mold cavity to form the desired shape. The mold is formed using sand, which acts as the expendable refractory material. The document also describes the various steps involved in sand casting and types of patterns used. Special casting processes provide advantages like better surface finish and dimensional accuracy compared to sand casting.
Casting is a manufacturing process where liquid material is poured into a mold and allowed to solidify. The solidified part is known as a casting. Investment casting, also known as lost-wax casting, involves creating a wax pattern, coating it with refractory material to create a ceramic mold, melting away the wax to leave a cavity, and pouring molten metal into the mold cavity. This allows for very intricate parts to be cast with close tolerances and smooth finishes. Investment casting is commonly used for parts that are difficult to machine from difficult to machine alloys like aluminum, copper, and steels.
Electron beam welding is a welding process that uses a beam of high-energy electrons to join materials. The electrons are generated by an electron gun and accelerated to near the speed of light by a high voltage between the cathode and anode. This gives the electrons sufficient kinetic energy to melt the welding material. The process occurs inside a vacuum chamber to prevent electrons from colliding with air molecules and losing energy. When the electron beam hits the workpiece, its kinetic energy converts to thermal energy, melting the edges to be joined together. The weld then solidifies, fusing the materials. Electron beam welding offers advantages like deep penetration welds, a small heat-affected zone, and the ability to weld heat-sensitive materials.
This document provides an overview of metal casting fundamentals. It discusses the importance of metal casting in manufacturing due to its ability to produce complex internal and external shapes in large quantities. The document outlines the basic steps in the casting process, including heating the metal, pouring it into a mold, and allowing it to solidify. It also summarizes the solidification process for pure metals and alloys, including factors that influence solidification time and techniques to control shrinkage and promote directional solidification. Finally, it categorizes common metal casting processes as either expendable or permanent mold and discusses their relative advantages.
Shell mold casting is a metal casting process that uses a resin-coated sand mixture to form a thin-walled mold shell around a metal pattern. The pattern is heated and pressed into the sand-resin mixture to form the shell, which is then cured in an oven. Two shell halves are joined to form the complete shell mold, into which molten metal is poured to create the casting. This allows for high-precision casting of small to medium parts like gear housings, cylinder heads, and connecting rods. The shell mold casting process provides advantages over sand casting like better surface finish and dimensional accuracy for the final casting.
This document discusses various casting processes including investment casting, plaster mold casting, ceramic mold casting, permanent mold casting, and die casting. It describes the key steps in each process and notes advantages and limitations. Defects that can occur in castings such as misruns, cold shuts, and shrinkage cavities are also outlined.
The document discusses various manufacturing processes. It provides details about metal casting processes like sand casting and special casting processes such as shell mold casting and investment casting. Sand casting involves pouring molten metal into a sand mold cavity to form the desired shape. The mold is formed using sand, which acts as the expendable refractory material. The document also describes the various steps involved in sand casting and types of patterns used. Special casting processes provide advantages like better surface finish and dimensional accuracy compared to sand casting.
Casting is a manufacturing process where liquid material is poured into a mold and allowed to solidify. The solidified part is known as a casting. Investment casting, also known as lost-wax casting, involves creating a wax pattern, coating it with refractory material to create a ceramic mold, melting away the wax to leave a cavity, and pouring molten metal into the mold cavity. This allows for very intricate parts to be cast with close tolerances and smooth finishes. Investment casting is commonly used for parts that are difficult to machine from difficult to machine alloys like aluminum, copper, and steels.
Electron beam welding is a welding process that uses a beam of high-energy electrons to join materials. The electrons are generated by an electron gun and accelerated to near the speed of light by a high voltage between the cathode and anode. This gives the electrons sufficient kinetic energy to melt the welding material. The process occurs inside a vacuum chamber to prevent electrons from colliding with air molecules and losing energy. When the electron beam hits the workpiece, its kinetic energy converts to thermal energy, melting the edges to be joined together. The weld then solidifies, fusing the materials. Electron beam welding offers advantages like deep penetration welds, a small heat-affected zone, and the ability to weld heat-sensitive materials.
This document provides an overview of metal casting fundamentals. It discusses the importance of metal casting in manufacturing due to its ability to produce complex internal and external shapes in large quantities. The document outlines the basic steps in the casting process, including heating the metal, pouring it into a mold, and allowing it to solidify. It also summarizes the solidification process for pure metals and alloys, including factors that influence solidification time and techniques to control shrinkage and promote directional solidification. Finally, it categorizes common metal casting processes as either expendable or permanent mold and discusses their relative advantages.
Shell mold casting is a metal casting process that uses a resin-coated sand mixture to form a thin-walled mold shell around a metal pattern. The pattern is heated and pressed into the sand-resin mixture to form the shell, which is then cured in an oven. Two shell halves are joined to form the complete shell mold, into which molten metal is poured to create the casting. This allows for high-precision casting of small to medium parts like gear housings, cylinder heads, and connecting rods. The shell mold casting process provides advantages over sand casting like better surface finish and dimensional accuracy for the final casting.
Casting is a manufacturing process where a liquid material is poured into a mold and allowed to solidify. There are several types of casting processes. Permanent mold casting uses reusable molds, usually made of metal. In the gravity process, preheated molds are coated with a refractory material before molten metal is poured in. Once solidified, the casting is removed. Slush casting is a variant that produces hollow castings. Shell mold casting uses a sand-resin mixture applied to a pattern to form a thin-walled reusable mold, allowing for complex geometries and high precision. Die casting forces molten metal into a mold cavity under high pressure to produce parts with excellent dimensional accuracy.
The document discusses various metal casting processes including sand casting, shell molding, expanded polystyrene casting, and investment casting. Sand casting is the most widely used process and involves making a sand mold around a pattern and pouring molten metal. Shell molding uses a thin shell mold made of sand and resin. Expanded polystyrene casting uses a polystyrene foam pattern that vaporizes when metal is poured. Investment casting, also called lost wax casting, involves making a wax pattern, coating it with refractory material, and melting the wax out of the mold before pouring metal.
The document discusses gravity die casting or permanent mold casting, which uses permanent molds made of materials like cast iron or steel to pour molten metal into without external pressure. It describes the design of permanent molds including parting lines, risers, and cores. The summary also lists some applications of permanent mold casting such as carburetor bodies, brake cylinders, and aircraft/missile castings.
Die Casting and its types By Raghav GuptaRaghav Gupta
This document provides an overview of different types of die casting processes and classifications of dies. It discusses the key aspects of various die casting methods including hot chamber die casting, cold chamber die casting, low pressure die casting, high pressure die casting, vacuum die casting, squeeze die casting, and gravity die casting. It also covers classifications of dies based on the number of impressions and materials poured, and provides examples of common applications for different metal alloys cast through die casting.
Different types of casting process and its applicationmangal iron
Casting involves pouring liquid metal into molds to form objects. The main types of casting are sand casting, permanent mold casting, centrifugal casting, continuous casting, and investment casting. Sand casting uses sand as the mold material and is inexpensive but less accurate. Permanent mold casting uses reusable metal molds for higher accuracy. Centrifugal casting forms thin-walled cylinders. Continuous casting produces long strips of metal in an automated process. Investment casting creates molds from liquid and is suitable for complex shapes.
The document discusses two die casting processes: gravity die casting and high pressure die casting. Gravity die casting involves pouring molten metal into an open mold, allowing it to cool and solidify. The mold is then tapped to release the finished casting. Common products made through gravity die casting include toasters, lawnmowers, and car wheel rims. High pressure die casting forces molten metal into a closed mold under high pressure to form shapes. Common products include golf club heads, car engine blocks, and radiators. Both processes result in castings that exhibit ejector pin marks and sprue/runner marks.
Casting is a manufacturing process where molten material is poured into a mold and solidifies to form a desired shape. There are two main categories of casting processes - expendable and non-expendable mold casting. Expendable processes use temporary molds like sand casting while non-expendable uses reusable molds. Key steps in casting include mold production, melting the material, and pouring it into the mold. Casting allows creating complex shapes in a single step and is well-suited for mass production. However, cast parts often require further machining and may be more brittle than other manufactured components.
1. Carbon dioxide moulding is a rapid hardening process where carbon dioxide gas is forced into molds made of dry silica sand, sodium silicate binder, and low moisture content to harden them.
2. Shell mould casting uses fine silica sand, phenolic resin, and a catalyst to form thin sand shells around a heated pattern that are then cured and assembled to form a mold.
3. Investment casting, also called lost wax casting, uses wax patterns coated with refractory material to form ceramic molds, the wax is then melted out before pouring molten metal.
The document discusses various casting processes including shell molding, expanded polystyrene casting, investment casting, plaster mold casting, ceramic mold casting, permanent mold casting, die casting, and centrifugal casting. It provides details on the key steps for each process as well as their advantages and limitations. Various furnace types for melting metals are also outlined, such as cupolas, direct fuel-fired furnaces, crucible furnaces, and electric-arc furnaces.
This PPT will let you know about metal casting and more specifically about the type of casting that is, Die casting, types of die casting, Cleaning of castings and inspection of casting
Permanent mould casting is a metal casting process that uses reusable molds to produce castings. There are four main permanent mould casting processes: gravity, slush, low pressure, and vacuum. Gravity process involves preheating the mold and pouring molten metal in. Slush casting produces hollow castings by allowing a shell to solidify before draining the remaining liquid. Low pressure uses gas pressure to push molten metal into the mold, while vacuum casting pulls molten metal into the mold in a vacuum. Permanent mould casting produces castings with good surface finish and dimensional accuracy.
Casting is a process where molten metal is poured into a mold and solidifies. It can create complex geometries and large parts. Molds are made of materials like sand, plaster or metal. Expendable molds are destroyed to remove parts while permanent molds can be reused. Direction solidification, from remote areas to risers, minimizes shrinkage. Riser design uses the minimum metal needed based on solidification calculations.
Castings - Aluminum Gravity die casting Processroshnipatel829
"Aluminium die casting processes are hush-hush as Ingot casting or Mould casting.
During the willingly style, head of the line or slight aluminium is appoint
into rolling ore (slab), extrusion alloy (billet) and wire waive ingot which
are as a consequence transformed in semi- and satisfied products... www.alphametalind.com"
The document provides an overview of the metal casting process. It discusses the history and basic features of casting, including the types of molds used. The main casting processes are classified as either expandable mold casting (such as sand casting) or permanent mold casting (such as die casting and centrifugal casting). Sand casting uses expendable sand molds, while die casting uses reusable steel dies and forces molten metal into the mold under high pressure. Selection of the appropriate casting process depends on factors like alloy, size, shape, tolerance, and economics of machining versus production costs.
Fettling is the process of preparing castings for use by removing unwanted material like gates, risers, fins, and imperfections. It involves several steps and techniques. First, dry sand cores are knocked out and gates and risers are removed through chipping, cutting, sawing, or abrasive machining depending on the material. Then fins and other projections on the casting surface are chipped off. Finally, the casting is cleaned through tumbling, shot blasting, or other modern blasting processes to produce a smooth, finished part meeting specifications. Fettling transforms crude castings into functional, high quality components through various removal and cleaning operations.
This presentation is all about the advanced casting process: shell molding, it is used by many small and big industries. The applications and the merits and demerits are described.
The document discusses different types of metal casting processes. It describes gravity die casting and pressure die casting as two types of die casting processes. Gravity die casting involves pouring molten metal into an open steel mold, allowing it to cool and solidify, then tapping the mold to release the casting. Pressure die casting forces metal under high pressure into molds called dies. The document also discusses vacuum permanent mold casting and compares attributes of different casting processes like maximum size, tolerance, and economic quantity.
Sand casting, investment casting, and die casting are the main casting methods discussed. Key topics include the casting process basics for each, phase change and shrinkage during solidification, heat transfer considerations, and pattern design guidelines. Variations and developments like continuous casting and 3D printing of investment tooling are also covered. Environmental impacts of casting such as energy use and emissions are reviewed.
...
Slush Casting is a traditional method of permanent mold casting process, where the molten metal is not allowed to completely solidify in the mold. When the desired thickness in obtained, the remaining molten metal in poured out. Slush casting method is an effective technique to cast hollow items like decorative pieces, components, ornaments, etc.
APPLICATIONS
Some casting of pewter is cast using slush casting method. Using pewter and other metals mainly hollow products are casted. Decorative and ornamental objects that are casted are as vase, bowls, candlesticks, lamps, statues, jewelery, animal miniatures, various collectibles etc. Small objects and components for industry like tankard handle, handles for hollow wares, etc.
ADVANTAGES
Slush casting is used to produce hollow parts without the use of cores
The desired thickness can be achieved by pouring our the left over molten metal
A variety of exquisitely designed casting can be casted for decorative and ornamental purpose.
The document discusses continuous casting of steel and defects that can occur during the continuous casting process. It provides details on:
- Continuous casting involves delivering liquid metal into a water-cooled copper mold where the cast section is formed and then continuously withdrawn for further solidification. More than 50% of current steel production is continuously cast.
- Defects originate from factors like mold oscillation, mold flux, segregation, and phase transformations. Common defects include cracks, blowholes, inclusions, segregation, and pipes.
- Cracks are caused by mechanical and thermal stresses during casting and processing. Blowholes are caused by insufficient deoxidation or humidity. Inclusions arise from physical-chemical effects
Principles and applications of the following processes: Forging
2.Principles and applications of the following processes: Rolling,
3.Extrusion, Wire drawing, and Spinning,
4.Powder metallurgy – Principal steps involved
5.Advantages, Disadvantages, and limitations of powder metallurgy
The document provides information on various casting processes for aluminum alloys. It discusses sand casting, die casting, semi-solid casting, squeeze casting, and Cosworth casting. For each process, it describes the key steps, suitability for different applications, advantages, and disadvantages. Sand casting allows for complex shapes at low cost but has rough finishes. Die casting facilitates high-volume production of parts with complex geometries. Semi-solid casting results in near-net shape parts with excellent dimensional accuracy. Squeeze casting produces stronger parts with a tighter grain structure.
Casting is a manufacturing process where a liquid material is poured into a mold and allowed to solidify. There are several types of casting processes. Permanent mold casting uses reusable molds, usually made of metal. In the gravity process, preheated molds are coated with a refractory material before molten metal is poured in. Once solidified, the casting is removed. Slush casting is a variant that produces hollow castings. Shell mold casting uses a sand-resin mixture applied to a pattern to form a thin-walled reusable mold, allowing for complex geometries and high precision. Die casting forces molten metal into a mold cavity under high pressure to produce parts with excellent dimensional accuracy.
The document discusses various metal casting processes including sand casting, shell molding, expanded polystyrene casting, and investment casting. Sand casting is the most widely used process and involves making a sand mold around a pattern and pouring molten metal. Shell molding uses a thin shell mold made of sand and resin. Expanded polystyrene casting uses a polystyrene foam pattern that vaporizes when metal is poured. Investment casting, also called lost wax casting, involves making a wax pattern, coating it with refractory material, and melting the wax out of the mold before pouring metal.
The document discusses gravity die casting or permanent mold casting, which uses permanent molds made of materials like cast iron or steel to pour molten metal into without external pressure. It describes the design of permanent molds including parting lines, risers, and cores. The summary also lists some applications of permanent mold casting such as carburetor bodies, brake cylinders, and aircraft/missile castings.
Die Casting and its types By Raghav GuptaRaghav Gupta
This document provides an overview of different types of die casting processes and classifications of dies. It discusses the key aspects of various die casting methods including hot chamber die casting, cold chamber die casting, low pressure die casting, high pressure die casting, vacuum die casting, squeeze die casting, and gravity die casting. It also covers classifications of dies based on the number of impressions and materials poured, and provides examples of common applications for different metal alloys cast through die casting.
Different types of casting process and its applicationmangal iron
Casting involves pouring liquid metal into molds to form objects. The main types of casting are sand casting, permanent mold casting, centrifugal casting, continuous casting, and investment casting. Sand casting uses sand as the mold material and is inexpensive but less accurate. Permanent mold casting uses reusable metal molds for higher accuracy. Centrifugal casting forms thin-walled cylinders. Continuous casting produces long strips of metal in an automated process. Investment casting creates molds from liquid and is suitable for complex shapes.
The document discusses two die casting processes: gravity die casting and high pressure die casting. Gravity die casting involves pouring molten metal into an open mold, allowing it to cool and solidify. The mold is then tapped to release the finished casting. Common products made through gravity die casting include toasters, lawnmowers, and car wheel rims. High pressure die casting forces molten metal into a closed mold under high pressure to form shapes. Common products include golf club heads, car engine blocks, and radiators. Both processes result in castings that exhibit ejector pin marks and sprue/runner marks.
Casting is a manufacturing process where molten material is poured into a mold and solidifies to form a desired shape. There are two main categories of casting processes - expendable and non-expendable mold casting. Expendable processes use temporary molds like sand casting while non-expendable uses reusable molds. Key steps in casting include mold production, melting the material, and pouring it into the mold. Casting allows creating complex shapes in a single step and is well-suited for mass production. However, cast parts often require further machining and may be more brittle than other manufactured components.
1. Carbon dioxide moulding is a rapid hardening process where carbon dioxide gas is forced into molds made of dry silica sand, sodium silicate binder, and low moisture content to harden them.
2. Shell mould casting uses fine silica sand, phenolic resin, and a catalyst to form thin sand shells around a heated pattern that are then cured and assembled to form a mold.
3. Investment casting, also called lost wax casting, uses wax patterns coated with refractory material to form ceramic molds, the wax is then melted out before pouring molten metal.
The document discusses various casting processes including shell molding, expanded polystyrene casting, investment casting, plaster mold casting, ceramic mold casting, permanent mold casting, die casting, and centrifugal casting. It provides details on the key steps for each process as well as their advantages and limitations. Various furnace types for melting metals are also outlined, such as cupolas, direct fuel-fired furnaces, crucible furnaces, and electric-arc furnaces.
This PPT will let you know about metal casting and more specifically about the type of casting that is, Die casting, types of die casting, Cleaning of castings and inspection of casting
Permanent mould casting is a metal casting process that uses reusable molds to produce castings. There are four main permanent mould casting processes: gravity, slush, low pressure, and vacuum. Gravity process involves preheating the mold and pouring molten metal in. Slush casting produces hollow castings by allowing a shell to solidify before draining the remaining liquid. Low pressure uses gas pressure to push molten metal into the mold, while vacuum casting pulls molten metal into the mold in a vacuum. Permanent mould casting produces castings with good surface finish and dimensional accuracy.
Casting is a process where molten metal is poured into a mold and solidifies. It can create complex geometries and large parts. Molds are made of materials like sand, plaster or metal. Expendable molds are destroyed to remove parts while permanent molds can be reused. Direction solidification, from remote areas to risers, minimizes shrinkage. Riser design uses the minimum metal needed based on solidification calculations.
Castings - Aluminum Gravity die casting Processroshnipatel829
"Aluminium die casting processes are hush-hush as Ingot casting or Mould casting.
During the willingly style, head of the line or slight aluminium is appoint
into rolling ore (slab), extrusion alloy (billet) and wire waive ingot which
are as a consequence transformed in semi- and satisfied products... www.alphametalind.com"
The document provides an overview of the metal casting process. It discusses the history and basic features of casting, including the types of molds used. The main casting processes are classified as either expandable mold casting (such as sand casting) or permanent mold casting (such as die casting and centrifugal casting). Sand casting uses expendable sand molds, while die casting uses reusable steel dies and forces molten metal into the mold under high pressure. Selection of the appropriate casting process depends on factors like alloy, size, shape, tolerance, and economics of machining versus production costs.
Fettling is the process of preparing castings for use by removing unwanted material like gates, risers, fins, and imperfections. It involves several steps and techniques. First, dry sand cores are knocked out and gates and risers are removed through chipping, cutting, sawing, or abrasive machining depending on the material. Then fins and other projections on the casting surface are chipped off. Finally, the casting is cleaned through tumbling, shot blasting, or other modern blasting processes to produce a smooth, finished part meeting specifications. Fettling transforms crude castings into functional, high quality components through various removal and cleaning operations.
This presentation is all about the advanced casting process: shell molding, it is used by many small and big industries. The applications and the merits and demerits are described.
The document discusses different types of metal casting processes. It describes gravity die casting and pressure die casting as two types of die casting processes. Gravity die casting involves pouring molten metal into an open steel mold, allowing it to cool and solidify, then tapping the mold to release the casting. Pressure die casting forces metal under high pressure into molds called dies. The document also discusses vacuum permanent mold casting and compares attributes of different casting processes like maximum size, tolerance, and economic quantity.
Sand casting, investment casting, and die casting are the main casting methods discussed. Key topics include the casting process basics for each, phase change and shrinkage during solidification, heat transfer considerations, and pattern design guidelines. Variations and developments like continuous casting and 3D printing of investment tooling are also covered. Environmental impacts of casting such as energy use and emissions are reviewed.
...
Slush Casting is a traditional method of permanent mold casting process, where the molten metal is not allowed to completely solidify in the mold. When the desired thickness in obtained, the remaining molten metal in poured out. Slush casting method is an effective technique to cast hollow items like decorative pieces, components, ornaments, etc.
APPLICATIONS
Some casting of pewter is cast using slush casting method. Using pewter and other metals mainly hollow products are casted. Decorative and ornamental objects that are casted are as vase, bowls, candlesticks, lamps, statues, jewelery, animal miniatures, various collectibles etc. Small objects and components for industry like tankard handle, handles for hollow wares, etc.
ADVANTAGES
Slush casting is used to produce hollow parts without the use of cores
The desired thickness can be achieved by pouring our the left over molten metal
A variety of exquisitely designed casting can be casted for decorative and ornamental purpose.
The document discusses continuous casting of steel and defects that can occur during the continuous casting process. It provides details on:
- Continuous casting involves delivering liquid metal into a water-cooled copper mold where the cast section is formed and then continuously withdrawn for further solidification. More than 50% of current steel production is continuously cast.
- Defects originate from factors like mold oscillation, mold flux, segregation, and phase transformations. Common defects include cracks, blowholes, inclusions, segregation, and pipes.
- Cracks are caused by mechanical and thermal stresses during casting and processing. Blowholes are caused by insufficient deoxidation or humidity. Inclusions arise from physical-chemical effects
Principles and applications of the following processes: Forging
2.Principles and applications of the following processes: Rolling,
3.Extrusion, Wire drawing, and Spinning,
4.Powder metallurgy – Principal steps involved
5.Advantages, Disadvantages, and limitations of powder metallurgy
The document provides information on various casting processes for aluminum alloys. It discusses sand casting, die casting, semi-solid casting, squeeze casting, and Cosworth casting. For each process, it describes the key steps, suitability for different applications, advantages, and disadvantages. Sand casting allows for complex shapes at low cost but has rough finishes. Die casting facilitates high-volume production of parts with complex geometries. Semi-solid casting results in near-net shape parts with excellent dimensional accuracy. Squeeze casting produces stronger parts with a tighter grain structure.
The document describes an automatic ingot feeder for furnaces. It uses two pneumatic cylinders to pick up aluminum ingots and move them slowly into the furnace tank using compressed air. A DC motor and microcontroller circuit are used to control the movement of the ingot material. The feeder aims to reduce difficult manual methods and labor previously used to load ingots.
IRJET- Effect of Soft Annealing on Copper, Brass and GunmetalIRJET Journal
The document analyzes the effect of soft annealing on copper, brass, and gunmetal samples. Rockwell hardness tests were performed before and after annealing samples at 850°C. Brass was found to be the hardest before annealing, while copper was hardest after annealing. Microstructure images showed grain refinement in copper after annealing but no visible changes in brass. Gunmetal samples developed cracks and pores after annealing. Wear tests found copper to be most resistant to wear, followed by brass, with gunmetal being the least resistant due to cracks and pores developed during annealing. In conclusion, annealing increased ductility and workability while decreasing hardness, with copper retaining higher hardness and wear resistance compared to brass and gunmetal after annealing.
1. Die casting is a metal casting process where molten metal is forced into a mold cavity under high pressure. This allows for intricate metal parts to be cast with high dimensional accuracy and consistency.
2. The main alloys used are zinc, aluminum, magnesium, copper, and tin-based alloys. Die casting is best suited for high volume production due to the large capital costs of the equipment and tooling.
3. The die casting process involves preparing lubricated dies, filling the mold cavity with molten metal under pressure, maintaining pressure until solidification, then ejecting and separating the castings from the shot and scrap.
IIIE SECTION A MANUFACTURING TECHNOLOGY NOTES 8.die castingsBhaskar Nagarajan
This document summarizes the die casting process used to produce metal castings. It discusses:
- Die casting forces molten metal into a mold cavity under high pressure (1500-25400 psi).
- Common materials used are zinc, aluminum, magnesium, copper, lead, and tin alloys.
- There are four main steps: die preparation, filling, ejection, and shakeout to separate scrap.
- Different types of die casting machines (hot chamber, cold chamber, vacuum) are used depending on the material and required pressure.
It is a near net shape process in which casting and forging is done in single step.
It is Referred by many names such as “squeeze casting” , “pressure infiltration”, “liquid metal forging”, “extrusion casting”, “liquid pressing'', “pressure crystallization”.
The document provides an overview of various casting methods including sand casting, investment casting, and die casting. It summarizes the key characteristics of each method such as typical metals used, size range, tolerances, surface finish, and process details. It also discusses related topics such as solidification and shrinkage, heat transfer considerations, pattern design guidelines, process variations, and potential environmental impacts.
Mild steel is a low-carbon steel with less than 0.25% carbon by weight, making it more ductile than higher-carbon steels. It is manufactured through processes like direct reduced iron and electric arc furnaces. Mild steel can be recycled without losing its properties. It has applications in construction materials, machinery parts, and other areas due to its strength, weldability, and lower cost compared to other steels. Some disadvantages are that it is heavier than other materials and prone to rusting.
Drop forging is a mass production technique that shapes hot metal between two dies using great force. There are two main types - closed die forging shapes metal inside molds, while open die forging positions the metal manually. Drop forging works metals both hot, to prevent hardening, and cold. It produces strong, complex parts in large quantities economically for runs over 50,000 units.
The document discusses various manufacturing processes and focuses on metal casting and joining techniques. It provides details about different types of casting processes like sand casting, special casting processes including centrifugal casting, CO2 process, investment casting and shell moulding. It also describes metal joining techniques such as different welding processes, brazing and soldering. Defects in castings and welded joints are also discussed. The document is divided into five units covering metal casting, joining, forming, sheet metal working and plastic component manufacturing processes.
Die casting is a metal casting process where molten metal is forced under high pressure into a mold cavity created using two hardened tool steel dies. Most die castings are made from non-ferrous metals like zinc, copper, aluminum, and magnesium. The casting equipment and metal dies represent large capital costs, but die casting allows for high-volume, low-cost production of small to medium sized castings.
The document discusses various manufacturing processes used in mechanical engineering. It covers primary shaping processes like casting and forging, machining processes, surface finishing processes, and joining processes. It then describes specific processes in more detail, including casting methods like sand casting and die casting. It also discusses hot working processes like hot rolling, hot forging, and extrusion which shape metals above their recrystallization temperature, as well as cold working processes below that temperature like cold rolling. Cold working increases strength and hardness but reduces ductility.
RAW MATEIAL and Heat Treatment process .pptSameerSutar8
This document provides an overview of a training programme on raw materials and heat treatment. It discusses the objectives of the training, which are to provide awareness of different raw material types, their characteristics, advantages, and examples used in the division. It then describes common product types like rolled products, forgings, castings, tubular products, and extrusions. The remainder of the document discusses these processes and material types in further detail, including definitions, considerations, defects, inspection methods, and more. It aims to educate participants on raw materials and manufacturing processes.
Types of melting furnaces,
2.Metal pouring equipment
3.Casting defects, remedies, Safety pollution,
4.Control and mechanization in foundries
5.Applications of Ferrous and nonferrous casting in automobiles
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process.
The document discusses cold working, hot working, and annealing processes for metals. Cold working involves plastic deformation at low temperatures to increase strength but reduce ductility through dislocation formation. Hot working above recrystallization temperatures can reduce imperfections through atomic mobility. Annealing heats metals slowly to allow recovery and recrystallization, reducing strength but increasing ductility. Examples of each process and their advantages/disadvantages are provided.
The document discusses cold working, hot working, and annealing processes for metals. Cold working involves plastic deformation at low temperatures to increase strength but reduce ductility through dislocation formation. Hot working above recrystallization temperatures can reduce imperfections through atomic mobility. Annealing heats metals slowly to allow recovery and recrystallization, reducing dislocations and improving properties like ductility. Examples of each process and their advantages/disadvantages are provided.
The document discusses cold working, hot working, and annealing processes for metals. Cold working involves plastic deformation at low temperatures to increase strength but reduce ductility through dislocation formation. Hot working above recrystallization temperatures can reduce imperfections through atomic mobility. Annealing heats metals slowly to allow recovery and recrystallization, reducing strength but increasing ductility. Examples of each process and their advantages/disadvantages are provided.
The document provides an overview of the steel melting shop (SMS) at Jindal Steel and Power Limited (JSPL). It describes the key equipment in the SMS including electric arc furnaces, ladle refining furnaces, vacuum degassing units, and continuous casters. It also summarizes the main processes like primary refining at the electric arc furnace and secondary refining at the ladle refining furnace. Safety rules and precautions for working in the SMS are highlighted at the end.
Similar to Ch3 specialcastproc Erdi Karaçal Mechanical Engineer University of Gaziantep (20)
The document describes the structure of metals and their properties. It includes figures and outlines explaining common crystal structures of metals like body-centered cubic, face-centered cubic, and hexagonal close-packed. It also describes defects in crystal structures like vacancies and dislocations, and how plastic deformation occurs in metals through slip and twinning. The effects of processes like solidification, recovery, and recrystallization on grain size and mechanical properties are summarized.
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Ch3 specialcastproc Erdi Karaçal Mechanical Engineer University of Gaziantep
1. 02/11/14 CHAPTER 3 SPECIAL CASTING
PROCESSES
1
CHAPTER 3
SPECIAL CASTING PROCESSES
3.1 INTRODUCTION
ME 333 PRODUCTION PROCESSES II
The process used for making a casting depends on;
-the quantity to be produced,
-the metal to be cast,
-the complexity of the part.
Sand molds are single-purpose molds, and are completely destroyed after the metal
has solidified.
Quite obvious the use of a permanent mold effect considerable saving in labor cost.
A summary of the various special casting methods, which will be discussed in this
chapter, is as follows:
A.Casting in metallic molds
B.Centrifugal casting
C.Precision or investment casting
D.Continuous casting
E.Shell molding
2. ME 333 PRODUCTION PROCESSES II
3.2 METAL MOLD CASTING PROCESSES
Permanent molds must be made of metals capable of withstanding high
temperatures.
Because of their high cost they are recommended only when many casting are to
be produced.
Although permanent molds are impractical for large castings and alloys of high
melting temperatures, they can be used advantageously for small and medium-sized
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castings that are manufactured in large quantities.
Die Casting: Die casting is a process in which molten metal is forced by
pressure into a metal mold known as a ‘die’.
The usual pressure is 100 to 125 atm.
It is the most widely used of any of the permanent mold processes.
There are two methods employed:
1. Cold-chamber Die Casting
2. Hot-chamber Die Casting
3. ME 333 PRODUCTION PROCESSES II
(1) Cold-chamber Die Casting:
Material to be cast is molten outside the machine.
Used for materials having high melting temperature Tm> 550°C, i.e. brass,
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aluminum, and magnesium.
(2) Hot-chamber Die Casting:
Materials to be cast is molten inside the machine.
Used for materials having low melting temperature Tm< 550°C, i.e. zinc, tin, and
lead.
(The principal distinction between the two is determined by the location of the melting
pot.
In the hot-chamber pot is included in the machine; and
In the cold-chamber pot is separate from the machine,
metal is introduced to injection cylinder by other means.)
4. ME 333 PRODUCTION PROCESSES II
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Fig. 3.1 Types of Die Casting
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Schematics of hot-chamber die-casting
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Schematics of cold-chamber die-casting
7. Die Casting Cavities
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Die Casting Products
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ME 333 PRODUCTION PROCESSES II
Advantages of die casting:
1. The process is rapid (since both dies and cores are permanent)
2. The surface quality is very good. (The smooth surface improves
appearance and reduces work required for other operations.)
3. Dimensional tolerances are very good comparing to sand casting. (The
size is so accurately controlled that little or no machining is necessary.)
4. The scrap loss is low since sprue, runners, and gates can be remelted.
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ME 333 PRODUCTION PROCESSES II
- The optimum production quantity ranges from 1,000 to 200,000 pieces.
- Max. Weight of brass die casting is about 2 kg, but aluminum die castings of
over 50 kg are common.
- Small to medium size castings can be made at a cycle rate of 100 to 800 die
fillings per hour.
- The life of dies depends on the metal cast and may range from 10,000 fillings
for brass to several million if zinc is used.
- If the part is big and complex, a single-cavity mold is used. If the parts are small
and quantity is large, multiple-cavity die can be used.
Optimum no. of parts: 1000-200,000
Weight of part: Brass about 2 kg
Aluminum about 50 kg
Die life: about 10,000 filling for Brass
Several millions for filling Zinc
Other methods of metal mold castings: low-pressure permanent mold casting,
gravity permanent mold casting, slush casting and pressed casting.
10. 3.3 DIE-CASTING ALLOYS
A relatively wide range of nonferrous alloys can be die-cast. The principal base
metals used are ZINC, ALUMUNIUM, MAGNESIUM, COPPER, LEAD and TIN. They
are classified in two groups:
1.Low-temperature alloys (casting temp. below 5500C),
2.High-temperature alloys
Zinc-Base Alloys : Over 75% of die castings are produced from zinc-base alloys.
Melting point is around 4000C. So, they are cast by Hot-chamber die casting.
ASTM Number Al Cu Mg Zn
AG40A(XXIII) 4.1 0.1 max 0.04 Remainder
AC41A(XXV) 4.1 1.0 0.04 Remainder
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ME 333 PRODUCTION PROCESSES II
Aluminum improves mechanical properties.
Copper improves tensile strength and ductility.
Magnesium makes casting stable in microstructure.
Zinc alloys are widely used in: automotive industry, washing machines,
refrigerators, business machines, etc.
11. Aluminum-Base Alloys : They are used due to their lightness in mass and
resistance to corrosion. Compared to zinc alloys they are more difficult to cast
(melting point around 5500C). Since molten aluminum will attack steel if kept in
continuous contact with it, the cold-chamber process generally is used.
ASTM
Number Cu Si Mg Al Uses
S12A&B -- 12 -- Remainder Large Intricate castings
S5C -- 5 -- Rem. Gen. Purpose
G8A 3 -- 8 Rem. High strength, res. corro.
SG100A&B -- 9.5 0.5 Rem. Gen. Purpose, Good Property,
excellent casting charac.
SC84B 3.5 9 -- Rem. Good machinability and
castability
Principal elements used as alloys with aluminum are SILICON, COPPER, and
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MAGNESIUM.
Silicon increases hardness and corrosion resisting properties, copper increases
mechanical properties, magnesium increases lightness and resistance to
impact. They are generally used in aerospace industry and production of
pistons.
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ME 333 PRODUCTION PROCESSES II
Copper-Base Alloys : Die casting of brass and bronze have presented a
greater problem due to their high casting temperature. Temperatures are
around 870 to 10400C, which need heat resisting die material. Copper alloys are
cold chamber die-cast.
ASTM
Number Cu Si Sn Pb Zn Uses
Z30A 57 min -- 1.5 1.5 30 min Yellow brass, good
machinability
Z5331A 65 1 -- -- Rem. Gen. Purpose casting, Corr.
res., castability
Z5144A 81 4 -- -- Rem.
High strength, hardness,
wear resistance-but most
difficult to mold
Copper-base alloys have extensive use in miscellaneous hardware, electric-machinery
parts, small gears, marine, automotive and aircraft fittings, chemical
apparatus, and numerous other small parts.
13. Magnesium-Base Alloys : It is alloyed principally with ALUMINUM, but may
contain small amounts of SILICON, MANGANESE, ZINC, COPPER, and
NICKEL. They have the lowest density. Their casting temperatures are around
670-7000C, so, cold chamber die casting is suitable.
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ASTM Number Al Zn Mn Si Cu Ni Mg
B94 9 0.5 0.13 0.5 0.3 0.03 Rem.
Zinc parts Aluminium parts
Copper parts
Magnesium parts
15. • Die Materials:
- Hot-worked tools steels
- Mold steels
- Maraging Steels
- Refractory Metals
Properties:
1.High hot strength
2.High temperature wear resistance
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16. ME 333 PRODUCTION PROCESSES II
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3. 4. CENTRIFUGAL CASTING (Savurma Döküm)
Centrifugal casting is the process of rotating a mold while the metal solidifies so
as to utilize centrifugal force to position the metal in the mold.
Castings of symmetrical shape lend themselves particularly to this method,
although many other types of casting can be produced.
Fig. 3.2 Centrifugal casting machine for casting steel or cast iron pipe
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ME 333 PRODUCTION PROCESSES II
Setup for true horizontal centrifugal casting
18. Centrifugal casting is often more economical than other methods.
Cores in cylindrical shapes and risers or feed-heads are both eliminated.
The castings have a dense metal structure with all impurities forced back to the
centre where frequently they can be machined out.
Piston rings weighing 50-100 grams to paper mill rolls weighing over 42 tons have
been cast in this manner.
Aluminum engine block uses centrifugally cast iron liners.
In some alloys, the heavier elements tend to be separated from the base metal,
known as “gravity segregation”.
The metal is forced against the walls on the mold with a centrifugal force of
approximately 70 g, which is a force 70 times that of the force of gravity alone on
the casting. Forces as high as 150 g have been used but are seldom found
necessary unless very thick-walled cylinders are being cast.
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19. Semi-centrifugal casting
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ME 333 PRODUCTION PROCESSES II
- In this method, centrifugal force is used to produce solid castings rather than
tubular parts.
- Density of the metal in the final casting is greater in the outer sections than at the
center of rotation.
- The process is used on parts in which the center of the casting is machined away,
such as wheels and pulleys.
20. 3.5. PRECISION OR INVESTMENT CASTING (Hassas Döküm)
Precision or investment casting employed techniques that enable very smooth
highly accurate castings to be made from both ferrous and non-ferrous alloys.
The process is useful in casting unmachinable alloys and radioactive metals.
There are a number of processes employed, but all incorporate a sand, ceramic,
plaster (alçı), or plastic shell made from an accurate pattern into which metal is
poured.
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Advantages of investment techniques are;
(1) intricate forms with undercuts can be cast;
(2) a very smooth surface is obtained with no parting line;
(3) dimensional accuracy is good;
(4) unmachinable parts can be cast;
(5) may replace die casting for short runs.
Main disadvantage is that it is expensive and not suitable for big parts.
21. Patterns are produced from wax (mum) or plastics which are subsequently melted
from the mold, leaving a cavity having all the details of the original pattern.
Present practice requires that a replica of the part to be cast made from steel or
brass.
From this replica a bismuth or lead-alloy split mold is made.
After wax is poured into the mold and solidification takes place, the mold is opened
and the wax pattern removed.
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Replica Split pattern Wax pattern
Wax Tree Plaster Coated
Fig. 3.3
Processes of
Precision or
Investment
Casting
22. Several patterns are usually assembled (Wax Tree) with necessary gates and risers
by heating the contact surfaces (wax welding) with a hot wire.
This cluster is molded by silica sand, plaster or ceramic slurries.
After the mold material gets strength, the mold is placed upside down and heated in
an oven for several hours to melt out the wax and to dry the mold.
The casting can be produced by gravity, vacuum, pressure, or centrifugal casting.
When the solidification finished, mold is broken away and gates and risers are cut-off.
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Replica Split pattern Wax pattern
Wax Tree Plaster Coated
Fig. 3.3
Processes of
Precision or
Investment
Casting
23. 02/11/14 CHAPTER 3 SPECIAL CASTING
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Figure
Schematic
illustration of
investment
casting, (lostwax
process).
Castings by this
method can be
made with very
fine detail and
from a variety of
metals.
23
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Investment casting of an integrally cast
rotor for a gas turbine.
(a)Wax pattern assembly.
(b)Ceramic shell around wax pattern.
(c)Wax is melted out and the mold is filled,
under a vacuum, with molten superalloy.
(d)The cast rotor, produced to net or near-net
shape.
Crosssection and microstructure
of two rotors:
(top) investment-cast;
(bottom) conventionally cast.
Examples
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3. 6. CONTINUOUS CASTING )
Continuous casting
consists of pouring
molten metal into one
end of a metal mold
open at both ends,
cooling rapidly, and
extracting the solid
product in a continuous
length from the other
end.
This is done with copper,
brass, bronze,
aluminum, and to a
growing extent, cast iron
and steel.
Fig. 3.4 A continuous casting rolling process
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Continuous casting is done for a number of purposes.
It is suitable for any shapes of uniform cross-section: round,
square, rectangular, hexagonal, fluted, gear toothed, and
many other forms; solid or hollow.
A growing use is to produce blooms, billets, and slabs for
rolling structural shapes. This is cheaper than rolling from
ingots.
A bloom has a square cross section with a minimum size of
15 by 15 cm.
A billet is smaller than a bloom and may have any square
section from 4 cm up to the size of a bloom.
Slabs may be rolled from either an ingot or a bloom. They
have a rectangular cross-sectional area with a minimum width
of 25 cm and a minimum thickness of 4 cm. The width is
always three or more times the thicknesses, which may be as
much as 40 cm. Plates, skelp and thin strips are rolled from
slab.
27. Continuous casting offers several advantages:
1. It yields 10% or more over rolling from ingots. Ingots have an appreciable
amount of porous end, which returns back to furnace. This waste is eliminated in
continuous casting.
2. A hollow center occurs from shrinkage in continuous casting but it is welded shut
after four rolling passes. Continuous cast structure is more uniform and dense.
3. Physical properties and surface finishes are comparable to those obtained in
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other metal mold processes.
Continuous casting is essentially automatic, and unit labor cost is low. Dies or
molds are made of copper or graphite.
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3. 7. SHELL MOLDING
ME 333 PRODUCTION PROCESSES II
Shell moulding is a casting process in which the mold is a thin shell (typically 9mm)
made of sand held together by a thermosetting resin binder.
Steps in shell moulding: (1) a match-plate or cope-and-drag metal pattern is heated and placed over a
box containing sand mixed with thermosetting resin;
(2) Box is inverted so that sand and resin fall onto the hot pattern, causinga layer of the mixture to
partially cure on the surface to form a hard shell;
(3) Box is repositioned so that loose, uncured particles drop away;
(4) Sand and shell is heated in oven for several minutes to complete curing
(5) Shell mold is stripped from the pattern
(6) Two halves of the shell mold are assembled, supported by sand or metal shot in a box,
(7) The finished casting is removed
29. Advantages:
1. Good surface finish (up to 2.5
mm)
2. Good dimensional accuracy
(±0.25 mm)
3. Suitable for mass production
Disadvantages:
Expensive metal pattern
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Area of application:
Mass production of steel casting of less than 10 kg
Two halves of a shell mold pattern
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3. 8. Expandable-pattern casting (Lost foam Process)
This process uses a polystyrene pattern, which evaporates upon contact with
molten metal to form a cavity for the casting; this process is also known as lost-foam
casting.
It has become one important casting process for ferrous and nonferrous
metals, particularly for the automative industry.
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3. 9. Casting Techniques for single-crystal components
Methods of casting turbine
blades: (a) directional
solidification; (b) method to
produce a single-crystal blade;
and (c) a single-crystal blade with
the constriction portion still
attached.