What is the metal powder injection molding technology? Which situations are applicable?

What is the metal powder injection molding technology? Which situations are applicable?

一、 What is metal powder injection molding technology?

Metal Injection Molding (MIM) is a new near net forming technology in the field of powder metallurgy. The process of MIM includes six steps: powder making, mixing powder and binder, injection molding, degreasing and debonding agent, sintering and solidification, and post treatment.

Specifically, powder making: MIM requires metal powder with a very small particle size, typically within the range of 0 to 30 microns, obtained through high-pressure water atomization or gas atomization methods; Mixing powder and binder: Fully mix metal powder and organic binder to form particles, and heat the mixed particles into a plasticized state; Injection molding: The mixture is squeezed into the mold cavity through an injection molding machine to form the initial blank of the part; Degreasing and debonding agent: Remove the adhesive from the part blank through chemical or thermal decomposition methods to obtain a part blank with only metal or a small amount of adhesive residue; Sintering solidification: Send the parts into the sintering furnace for solidification, further removing residual adhesive; Post treatment: By means of quenching heat treatment, chemical heat treatment, steam treatment, etc., the internal pores of the parts are reduced, the compactness of the parts is improved, the strength, corrosion resistance, and wear resistance of the parts are improved, and the final parts are formed.

二、 What situations are suitable for metal powder injection molding technology?

At present, MIM is widely used in electronic products, watches, small medical devices, automotive engine parts, sports equipment, light weapons, and other fields. Compared with traditional mechanical processing, MIM technology can effectively utilize materials and shape complex structural parts, making it one of the effective supplementary methods for traditional processing.

The processing applicable to MIM technology can be classified into the following situations:

1. In traditional cutting or grinding processes, parts with significant material loss and long processing periods are suitable for cost reduction through MIM technology.

2. MIM can be used for mass production, and parts that meet certain conditions for mass production but have lower demand relative to mold cost are suitable for MIM technology.

3. Metals that are difficult to cut, such as titanium, nickel alloys, etc., can be considered to be manufactured through MIM technology, which will improve the accuracy of the product compared to traditional processing and significantly save materials.

4. Parts with complex geometric shapes, such as surface threads, knurling, cross holes, etc., are difficult to achieve in traditional powder metallurgy. In cutting, multi axis or multi reference parts that require multiple changes in processing stations are suitable for processing through MIM technology.

5. Parts that need to be processed by different material combinations, such as parts made of metal and ceramic composite materials, or parts made of different material overlays, such as hard magnetic soft magnetic, magnetic non magnetic, conductive insulation material overlays.

三、 Is metal powder injection molding technology suitable for materials?

The range of materials applicable to MIM technology is relatively broad. In principle, powder materials with a melting point above the sintering temperature can be used to manufacture parts through MIM technology. Considering economic efficiency, the commonly used materials currently include iron based, nickel based, low alloy, hard alloy, etc