Advantages of Metal Injection Molding over Powder Metallurgy

MIM is the development of the traditional PM process. The standard PM process involves compacting a lubricated powder mixture in a rigid mold via uniaxial pressure, ejecting the compact from the mold, and then sintering it. Millions of fairly complex shapes can be produced, but parts with undercuts or bulges at right angles to the direction of pressing cannot be directly produced because the part must be ejected, i.e. pushed out of the mold cavity. The MIM process essentially removes this limitation.
For many years, it has been common to use thermoplastic injection molding to produce fairly complex parts, and such parts are relatively cheap. However, their mechanical properties are poor for engineering applications. MIM adds very high volume fractions of metal powders to the mix to produce plastic bonded metal or ceramic parts. Carefully removing the plastic binder leaves a metal or ceramic skeleton, which can be sintered in much the same way as a molded part. When sintered to a density of 95% or higher, the mechanical properties are generally better than conventional PM parts. If the shape allows parts to be produced by conventional pressing and sintering, then MIM will in most cases be too expensive. However, MIM is less expensive than machining if the required quantity of complex shaped parts is above a certain quantity.
The impact of mass production on costs is that, for example, for a small part weighing 4.5 grams, the cost per part drops from $1.40 for 250,000 units per year to $0.20 for 3 million units or more per year (although larger parts The smaller is the cost gap between 250,000 yuan and 3 million yuan).
The competing process with MIM is investment casting, and for most properties of parts produced by both processes, MIM is superior, especially with high casting quantities, and of course with non-castable alloys, as well as the many possible Shapes cannot be produced by means other than MIM. For example, for high-precision endoscope accessories, in order to maintain high precision and dexterity, Shenzhen Yujiaxin Technology Co., Ltd. generally adopts MIM technology to customize products that meet customer requirements. If you are interested in learning more about how we can help your company manufacture high-precision and aesthetically pleasing medical device parts, please feel free to contact us and we will be happy to serve you.