Metal powder injection molding technology and materials will continue to improve in the future

Metal powder injection molding technology and materials will continue to improve in the future

In the past 30 years, the parts produced by metal powder injection molding technology have become increasingly complex, and its application fields have covered a wide range of different industries. With the growing demand of the market for high-quality parts with small geometric deformation and strong material performance, MIM technology has been integrated into production lines of all walks of life, such as the manufacturing of MIM auto parts, MIM medical devices and MIM mobile phone accessories. The field of high power density (such as modern automobile engine, powertrain and mechanical manufacturing) requires small and compact mechanical system, because it can provide greater innovation potential and higher production efficiency. In addition, the complex metal powder injection molding technology parts (powder metallurgy micro gear and powder metallurgy small module gear) also play a lot of advantages, for example, it can effectively reduce the assembly time of notebook computers, mobile phones and other mass production products.

In order to meet the needs of the industry for the continuous development of technical requirements and relevant specifications, leading manufacturers in the MIM industry must explore the growth space of metal powder injection molding technology and equipment in terms of accuracy and efficiency. At present, the restrictions on mechanical and chemical properties and optical appearance of parts are mainly caused by the following aspects: uneven mixing of geometrically deformed powder and raw materials; Density fluctuation caused by injection and degreasing stage; The temperature in the sintering furnace is uneven. Process gas management with inaccurate chemical decomposition and discoloration; The binder is deposited again in the second degreasing step; Residual sintering furnace pollutants. In addition to these technical restrictions, the highly competitive market environment will transfer the cost pressure to the parts manufacturers. Because of this, in order to promote the industry to move forward, zhongwei precision research found that higher income, sophisticated production equipment and materials are crucial.

In addition to the high purchase cost of raw materials (such as fine metal powder, polymer binder and ready injection raw materials), high-temperature sintering is one of the main cost drivers in metal powder injection molding technology. The investment and operation cost of degreasing sintering furnace are the key to the competitiveness of metal powder injection molding parts manufacturers. In addition, selecting the appropriate furnace type according to the specific production situation is the prerequisite for success in the metal powder injection molding technology industry.

Without considering customized and highly specialized systems, most sintering furnaces on the market can be divided into periodic vacuum furnaces and continuous atmosphere furnaces. The brown parts after injection molding and catalytic/degreasing contain residual polymer, and both furnaces provide the solution of removing polymer by thermal method. Through practice, Zhongwei has found that it is appropriate to make full use of continuous atmosphere furnace if it is a relatively large part with completely consistent mass production or similar shape. In this case, the cycle is short and the sintering capacity is high, which can obtain favorable cost-benefit rate. However, in medium and small scale production lines, this continuous atmosphere furnace with annual output of 150~200t, high input cost and large volume is not economical. Moreover, the continuous atmosphere furnace requires longer shutdown time in maintenance, reducing production flexibility.

If continuous production and low maintenance costs are maintained, MIM experts suggest that the adhesive collection system of metal powder injection molding technology should be considered to protect key structural components. The separation of gas flow and binder is realized in modern vacuum sintering furnace. A vacuum pump realizes the hot zone vacuum pumping, which is composed of a Roots pump supported by a mechanical pump. The high temperature and high speed process gas carries the saturated evaporated polymer material and is pumped out through the exhaust pipe at the bottom of the vacuum furnace shell. When the air flow of metal powder injection molding technology turns due to the influence of the cold pipe wall, it suddenly slows down and cools, resulting in the instant re condensation of some gaseous binders; In this way, up to 20%~25% of the binder material has been deposited in the pipeline, which will lead to pipeline plugging.

The above is related to metal powder injection molding (MIM) technology told by zhongwei Precision Editor. The materials of metal powder injection molding technology will continue to improve in the future, and the application fields will also be more diversified. If you want to know more about MIM technology and MIM materials, please consult the professional team of zhongwei Precision Metal Powder Injection Molding MIM technology to answer for you!