MIM Powder and Milling Technology for Metal Injection Molding
Dec 01, 2022
MIM Powder and Milling Technology for Metal Injection Molding
MIM has high requirements for raw powder, and the powder selection should be conducive to mixing, injection molding, degreasing and sintering, which is often contradictory. The research of MIM raw powder includes: shape, particle size, particle size composition, specific surface area, etc. Are you familiar with MIM powder and powder making technology of metal injection molding? Answer from zhongwei precision powder metallurgy manufacturer:
Because the requirements of MIM raw powder are very strict, the price of MIM raw powder is usually very high, and some even reach 10 times of the price of traditional PM powder. This is the key factor limiting the wide application of MIM technology. Currently, the MIM is being produced. The methods of using raw material powder mainly include carbonyl method, ultra-high pressure water atomization method, high-pressure gas atomization method, etc.
Binder is the core of MIM technology. In MIM, adhesives have two basic functions: enhancing fluidity to fit injection molding and maintain the shape of green blanks. In addition, it should be easy to remove. Non pollution, non-toxic, reasonable cost, etc., for this purpose, a variety of adhesives have emerged. In recent years, from individual experience to degreasing methods and requirements for adhesive functions, targeted adhesive system design direction.
The adhesive is usually composed of low molecular weight components, high molecular weight components and some necessary additives. Low molecular components have low viscosity, good fluidity and are easy to remove. The high molecular component has high viscosity and high strength, and maintains the strength of the formed blank. Properly proportion the two to obtain high powder loading capacity, and finally obtain products with high precision and high uniformity.
Mixing is the process of mixing metal powders and adhesives to obtain a uniform feed. Because the properties of the feed determine the performance of the final injection molding product, the mixing process is very important. This involves various factors, such as the way and order of adding adhesive and powder, mixing temperature, characteristics of mixing device, etc. This treatment step is at an empirical level, and the important indicators for the final evaluation of the mixing process are the uniformity and consistency of the feed obtained.
The mixing method is usually to add high melting point components to melt them, then cool them, add low melting point components, and then add metal powder in batches. This can prevent the vaporization or decomposition of low melting point components, and the addition of metal powder in batches can prevent the rapid increase of torque caused by sharp temperature drop, and reduce equipment loss. These are the information about MIM powder and powder making technology of metal injection molding. Friends with questions can continue to pay attention to the update of zhongwei precision official website.
