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Dongguan Goodjob Precision Components Co.,Ltd.

ADD: No.68, Changsheng North Road, Dalang,Dongguan,Guangdong,China

Tel: +86-769-23327726

Fax: +86-769-23327736


11. Q: What industries is applied to aluminium forged parts?

A: Aluminum forging has been proved forging type in a wide of applications such as Aerospace, Transportation, Telecommunication, Energy electronics etc. especially for Automotive industry. Compared with aluminum casting, aluminum forging is more reliable for the designer to consider when there is a requirement on strength. The design of aluminum forging can often provide the new part desired light weight and high strength at low cost.


12. Q: What are the features of the aluminum forging parts?

A: Features of aluminum forging parts:

(1) The density of aluminum alloy forgings is small which is only 34% of steel forgings and 30% of copper forgings. So aluminum alloy forging is ideal material for lightweight.

(2) The internal structure is fine, uniform and without defects, and its reliability is much higher than that of aluminum alloy castings and die castings, and also higher than that of other materials castings.

(3) The plasticity of aluminum alloy is good. It can be processed into a variety of high precision forging parts with complex shapes. The machining allowance is small, only about 20% of the residual amount of aluminum alloy drawing plate is processed, which greatly saves time and cost.

(4) Good corrosion resistance, thermal conductivity and non-magnetic properties.

(5) The surface is smooth and nice, and the surface treatment is good and durable.

13. Q: What is heat treatment?

A: Heat treating (or heat treatment) is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve a desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, normalizing and quenching. It is noteworthy that while the term heat treatment applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding.


14. Q: What techniques of heat treatment?

A: annealing, normalizing, stress relieving, aging, quenching, tempering, hardening. Carburizing, Nitriding, carbonitriding.


15.Q: What is Normalizing in heat treatment?

A: Normalizing is an annealing heat treatment used to refine the grains and produce a more uniform and desirable size distribution. Normalizing is accomplished by heating the material to a temperature above its upper critical temperature(eg. Just above 1333 ˚F F for most fastener-related steels). After sufficient time has been allowed for the alloy to completely transform to austenite, the metal is allowed to cool in the air.


16. Q: What is Tempering in heat treatment?

A: Untempered martensitic steel, while very hard, is too brittle to be useful for most applications. A method for alleviating this problem is called tempering. Most applications require that quenched parts be tempered. Tempering consists of heating steel below the lower critical temperature, (often from 400 to 1105 ˚F or 205 to 595 ˚C, depending on the desired results), to impart some toughness. Higher tempering temperatures (may be up to 1,300 ˚F or 700 ˚C, depending on the alloy and application) are sometimes used to impart further ductility, although some yield strength is lost.


17. Q: What is called Aging in heat treatment?

A: Some metals are classified as precipitation hardening metals. When a precipitation hardening alloy is quenched, its alloying elements will be trapped in solution, resulting in a soft metal. Aging a "solutionized" metal will allow the alloying elements to diffuse through the microstructure and form intermetallic particles. These intermetallic particles will nucleate and fall out of solution and act as a reinforcing phase, thereby increasing the strength of the alloy. Alloys may age "naturally" meaning that the precipitates form at room temperature, or they may age "artificially" when precipitates only form at elevated temperatures. In some applications, naturally aging alloys may be stored in a freezer to prevent hardening until after further operations - assembly of rivets, for example, may be easier with a softer part.


18. Q: What is called Quenching in heat treatment?

A: Quenching is a process of cooling a metal at a rapid rate. This is most often done to produce a martensite transformation. In ferrous alloys, this will often produce a harder metal, while non-ferrous alloys will usually become softer than normal.

To harden by quenching, a metal (usually steel or cast iron) must be heated above the upper critical temperature and then quickly cooled. Depending on the alloy and other considerations (such as concern for maximum hardness vs. cracking and distortion), cooling may be done with forced air or other gases, (such as nitrogen).


19.Q: What is annealing in heat treatment?

A: Annealing consists of heating a metal to a specific temperature and then cooling at a rate that will produce a refined microstructure, either fully or partially separating the constituents. The rate of cooling is generally slow. Annealing is most often used to soften a metal for cold working, to improve machinability, or to enhance properties like electrical conductivity.

20. Q: What is carburizing?

A: Carburizing also referred to as Case Hardening, is a heat treatment process that produces a surface which is resistant to wear, while maintaining toughness and strength of the core. This treatment is applied to low carbon steel parts after machining, as well as high alloy steel bearings, gears, and other components.