MIM Technology: Invisible Engine for Automotive Precision Manufacturing

In the wave of transformation towards lightweight and intelligent in the automotive industry, metal injection molding (MIM) technology has become a key support for core component manufacturing due to its dual advantages of complex molding and mass production. From powertrain to intelligent control, the production difficulties of many difficult parts have been solved through MIM technology, and its application cases are spread throughout the core fields of automotive manufacturing.

The power system is a key application scenario of MIM technology, and the manufacturing of turbocharger components can be regarded as a model. The turbocharger turbine needs to operate at high speed in a high-temperature exhaust environment, which not only includes complex blade surfaces and precision mounting holes, but also needs to withstand temperatures exceeding 600 ℃. BASF, a German company, adopts the Catamold process and uses nickel based ultra-high temperature alloy powder as raw material to form turbine components through MIM technology. Its room temperature tensile strength is increased by more than 20% compared to precision castings. The domestic team from Beijing University of Science and Technology uses K418 alloy powder as raw material, optimizes the binder formula and sintering process, and produces a turbocharged engine with a density of 98%, fully meeting the high-strength requirements of the engine.

The precision upgrade of fuel injection systems also relies on MIM technology. The magnetic components such as the iron core and armature of automotive fuel injectors need to have high-precision magnetic permeability and mechanical properties. Traditional forging processes are not only cumbersome, but also suffer from material waste. India US MIM Technology Co., Ltd. uses 440C stainless steel powder to manufacture fuel injector sealing supports through MIM process. The component has multi angle grooves and top micro holes, which can be formed in one go without subsequent processing. The single piece cost is reduced by 35% compared to traditional processes, and the fuel efficiency is improved by 10% -20%. The density of these components can reach 7.65g/cm ³, and the tensile strength can reach up to 1600MPa, far exceeding the traditional process level.

MIM technology demonstrates powerful adaptability to complex structures in intelligent control and safety systems. The bending connector of the car rearview mirror contains multiple precision slots, and traditional processing is prone to dimensional deviations, leading to assembly difficulties. Mingyang Technology of the Beijing Stock Exchange uses MIM technology to mass produce this component. By accurately controlling the mold shrinkage, the dimensional tolerance of the part is controlled within ± 0.3%, and the assembly pass rate is increased to over 99%. The ignition pin, D-axis and other core components of the airbag are made of 17-4PH stainless steel through MIM, with a hardness of 38-41HRC and a tensile strength of over 1100MPa. They can achieve stable triggering under instantaneous impact, ensuring driving safety.

Nowadays, the application proportion of MIM technology in the automotive field has reached 13%, becoming the third largest application market after light weapons and medical fields. From power turbines to safety components, MIM technology has achieved high-precision and low-cost mass production of complex parts with the advantage of near net forming. In the future, with the development of new energy vehicles, its application in fields such as motor gears and battery structural components will be more extensive, continuously empowering the upgrading of the automotive industry.