Metal injection molding technology in the application of automobile industry
Metal Injection Molding (Metal Powder Injection Molding, or MIM) is a traditional Powder metallurgy technology and plastic Injection Molding technology of the combination of a high and new technology.MIM began in the late 1970 s, in the past the lack of proper powder and raw material price is too high, imperfect knowledge platform, the technology is not mature, people understand and market accept time is not long, production (including mold manufacturing cycle is too long, investment is not enough, its development and application is relatively slow.To solve the problem of the difficulty of MIM technology, promote the MIM technology is practical, the mid – 80 – the United States has an advanced powder processing plan, the research content covers 18 topics related to the injection molding.Then Japan, Germany, etc. Also a positive research on the development of MIM.With the deepening of the MIM research and development of new type of binder, pulverizing technology and the advance of degreasing process, to the early 90 s has achieved industrialization.After more than 20 years of efforts, now the MIM has become the international field of powder metallurgy is developing rapidly, the most promising a new net shaping technology and has been hailed as “the most popular metal parts forming technology”.
At present, among national automobile industry competition is intense, win in the fierce competition of the premise condition is to use low cost technology to produce high quality products, metal powder injection molding (MIM) the development of technology has greatly promoted the development of the automotive industry.
MIM technology with a large amount of binder as a means of flow, so can be arbitrary shape like plastic industry all sorts of complex metal parts, this is a traditional powder metallurgy mold process cannot reach.And because the injection molding is a kind of net-shape forming technology, with almost no subsequent processing, parts manufacturing cost is greatly reduced, before need dozens of machining sequence of parts can be achieved once forming.In addition, because of the uniformity of flow during injection molding filling cavity, density uniformity throughout the MIM products, to avoid the PM moulding process inevitably density inhomogeneity.And because the fine powder, the product can reach very high density after sintering, and the mechanical properties of MIM products superior to moulding and precision casting products.At present, the MIM technology is mainly used for automobile fuel supply system in the automobile industry of nozzle, seat belt accessories, automotive electric control device accessories, airbag sensor parts and production of automobile interior trim parts.
Automobile manufacturing industry is the biggest user of MIM part, 6 o % of total sales accounted for about the MIM parts in according to the American metal market statistics, in 1990 the United States every 10 cars with MIM parts.With l5 9 kg, 1999.9 kg.Increased by 46% with M1M technology in the production of auto parts material is generally 2 Fe, ni, Fe – 0.4 c a 1 cr a 0.75 mn a 0.2 mo Fe 2 c_0 a 0.5 cr a 0.6 a 0 5 mn ni and other low alloy steel, also use a small amount of stainless steel.