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Designers and materials engineers are recognizing the increasing importance of resistance to impact and fatigue as a portion of total component reliability. With the use of proper materials and heat treatments, if required, improved impact strength of forged components is achievable. The resulting higher strength-to-weight ratio can be used to reduce section thickness in part designs without jeopardizing performance characteristics or safety. Weight reduction, even in parts produced from less expensive materials, can amount to a considerable cost savings over the life of a product run. The consistency of material from one forging to the next, and between separate quantities of forgings is extremely high. Forged parts are made through a controlled sequence of production steps rather than random flow of material into the desired shape. Uniformity of composition and structure piece-to-piece, lot-to-lot, assure reproducible response to heat treatment, minimum variation in machinability, and consistent property levels of finished parts. Dimensional characteristics are remarkably stable. Successive forgings are produced from the same die impression, and because die impressions exert control over all contours of the forged part, the possibility of transfer distortion is eliminated. For cryogenic applications, forgings have the necessary toughness, high strength-to-weight ratios, and freedom from ductile-brittle transition problems. Forgings are produced economically in an extremely broad range of sizes. With the increased use of special punching, piercing, shearing, trimming, and coining operations, there have been substantial increases in the range of economical forging shapes and the feasibility of improved precision. However, parts with small holes, internal passages, re-entrant pockets, and severe draft limitations usually require more elaborate forging tooling and more complex processing, and are therefore usually more economical in larger sizes. |
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Forging versus
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Forging Advantages When Using A Similar Alloy
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Casting
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Welding/Fabricating
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Machining
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| Powder metal Additional Informations on Comparisons |
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| Composites/Plastics Additional Informations on Comparisons |
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| North American Forges to Offshore Competition | . |
| Forgings are superior to metal parts produced by other methods in their compatibility with other manufacturing processes The characteristically uniform refinement of crystalline structure in forged components assures superior response to all forms of heat treatment, maximum possible development of desired properties, and unequaled uniformity. Because forged components of weldable materials have a near absence of structural defects, material at welding surfaces offers the best possible opportunity for strong, efficient welds by any welding technique. Again, the near absence of internal discontinuities or surface inclusions in forgings provides a dependable machining base for metal-cutting processes such as turning, milling, drilling, boring, broaching, and shear spinning; and shaping processes such as electrochemical machining, chemical milling, electrical-discharge machining, and plasma jet techniques. Forged parts are readily fabricated by assembling processes such as welding, bolting, or riveting. More importantly, single-piece forgings can often be designed to eliminate the need for assemblies. In many applications, forgings are ready for use without surface conditioning or machining. Forged surfaces are suited to plating, polishing, painting, or treatment with decorative or protective coatings. |
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Metal
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Characteristic
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Application
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| Aluminum |
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Primarily for structural and engine applications in the aircraft and transportation industries where temperatures do not exceed 400°F.
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| Magnesium |
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Usually employed at service temperatures lower than 500°F but certain alloys provide short-time service to 700°F. |
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Copper,
Brass, Bronze
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Important for applications requiring corrosion resistance. | |
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Low-Carbon and
Low-Alloy Steels
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Comprise the greatest volume of forgings produced for service applications up to 900°F. | |
| Microalloy/ HSLA Steels |
Various automotive and truck applications including crankshafts, connecting rods, yokes, pistons, suspension and steering components, spindles, hubs, and trunio
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Special-Alloy
Steels
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Used in transportation, mining, industrial and agricultural equipment, as well as high-stress applications in missiles and aircraft.
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| Stainless Steel |
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Used in pressure vessels, steam turbines, and many other applications in the chemical, food processing, petroleum, and hospital services industries. Used for high-stress service at temperatures up to 1,250°F and low-stress service to 1,800°F and higher.
Nickel-Base
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Nickel-Base
Superalloy
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Service in the 1,200-1,800°F range. Structural shapes, turbine components, and fittings and valves.
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| Titanium |
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Used primarily in the temperature services to 1,000°F. Configurations nearly identical to steel parts are forgeable and 40% lighter in weight. Aircraft-engine components and structurals, ship components, and valves and fittings in transportation and chemical industries.
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| Refractory Metal |
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High-temperature applications involving advanced chemical, electrical, and nuclear propulsion systems and flight vehicles. |
| Beryllium |
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Used primarily in nuclear, structural, and heat-sink applications. |
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Zirconium
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Produced in relatively limited quantities and used almost exclusively in nuclear applications.
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Queen City Forging Company
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Member, Forging Industry Association |
This page discusses metalworking processes,strong,tough,reliable,structural integrity,heat treatment,consistent machinability,directional strength,greater metallurgical soundness,mechanical properties of metal,solidification,ductility,resistance to impact,fatigue,recrystallization,grain refinement,grain flow,uniformity of composition and structure,die impression,cryogenic applications,ductile-brittle transition,punching,piercing,shearing,trimming,coining,tooling,Casting,Welding/Fabricating,Machining,Powder metal,Composites/Plastics,weldable,welding,turning,milling,drilling,boring,broaching,shear spinning,electrochemical machining,chemical milling,electrical-discharge machining,plasma jet techniques,bolting,riveting,single-piece forgings,plating,polishing,painting,treatment with decorative or protective coatings,Aluminum,Magnesium,Copper, Brass, Bronze,Low-Carbon and Low-Alloy Steels,Microalloy/HSLA Steels,Special-Alloy Steels,Stainless Steel,Nickel-Base Superalloy,Refractory Metal,Beryllium,Zirconium.