In the metal injection molding MIM, the binder plays a very important role, it directly affects the mixing, injection molding, degreasing and other processes, and has a great impact on the quality, degreasing and dimensional accuracy of the metal powder injection molding blank, alloy composition, etc. Its role is to bond the metal powder particles, so that the mixture is heated into a material with rheological characteristics in the barrel of the injection machine, that is, it becomes a carrier to drive the flow of powder. Therefore, the choice of binder is the key to the formation of the whole powder injection. Requirements for binder: a small amount, that is, to ensure that the mixture has better rheology while using as little binder as possible; b No reaction, i.e. no chemical reaction with metal powder; c Easy to remove, no residue in the product. The soul of binder powder metallurgy MIM process, its addition and removal is the key technology of MIM, and the degreasing process used in the binder system is a key research topic at home and abroad. The binders used in MIM include thermoplastic systems, thermoset systems, water-soluble systems, gel systems and special systems, each of which has its own advantages and disadvantages. Thermoplastic binder system is the mainstream and precursor of MIM binder, and people focus on improving the rheological properties of feeding grains,A lot of research has been carried out to reduce degreasing deformation and shorten the degreasing time, and some special agents including polyacetal binders have been developed。The special system has enabled the further development of thermoplastic binder system. But the research and development of binders lacks with powders
Affinity, mixing of powders and binders, rheological and thermodynamic properties of binders and feeds under various conditions,The influence of binders on degreasing and product properties provides universal principles and theoretical basis for the selection of binders, which is undoubtedly unique It has a very positive meaning. The development of a new and efficient binder system is also the focus of MIM technology .
Post time: Jun-23-2022