Powder Loads Powder metallurgy injection molding parts
Powder injection molding powder injection molding is a new type of near-net size molding technology, is used to produce smaller size and complex shape and surface of the product, compared with the traditional processing technology, powder injection into the technical cost advantages. The current powder metallurgy injection molding parts cross-sectional size of 25 ~ 50mm, length up to 150mm, between the single weight of 0.1g ~ 150g, so powder metallurgy injection molding suitable for the production of large quantities, complex shape, small size parts. PIM combines powder metallurgy and plastic injection molding processes for the production of metals, ceramic products and refractory metal parts. The process includes the following four processes: mixing, injection molding,degreasing, sintering. When injection molding technology used in ceramics and metal, known as ceramic powder injection molding (CIM) and metal powder injection molding (Metal Injection Molding, referred to as MIM) Principle Powder injection molding is the powder and binder Evenly mixed to make it flow, in the injection extruder by a certain temperature and pressure, into the mold forming.
This process can produce complex bricks, the resulting billet by solvent treatment or special removal of the binder after the thermal decomposition furnace, and then sintering its products density of up to 95% or more, line shrinkage The rate of up to 15% to 25%, and then according to the need for sintering products for precision, a small amount of processing and surface strengthening treatment processes, the final available products. Ceramic powder injection molding technology from the polymer injection molding, with high polymer polymer at high temperature melting, low temperature coagulation characteristics of the molding, after molding and then remove the polymer. Compared with the traditional ceramic processing technology, ceramic powder injection molding technology to be simple and more able to create a variety of complex shapes of high-precision ceramic parts, and easy to scale and automated production, has been widely used in aviation, military, automotive , Electronics, machinery and medical equipment and other industries. CIM basic process includes four steps: 1. Binder and ceramic powder mixing 2. Molding 3. Degreasing 4. Sintering where the degreasing is ceramic injection molding technology Metal powder injection molding technology is in the traditional injection molding and powder metallurgy Based on the development of a new type of metal injection molding, has been widely used in electronic information, medical equipment, automotive, aerospace and other fields.
Injection molding process, especially suitable for mass production of small, complex high-density metal or metal compounds products, expanding the application of powder metallurgy technology. Since the 20th century, 70 years since the rapid development, has great potential, known as the "21st century forming technology." MIM process is mainly divided into three stages of the mixture of binder and metal powder injection molding; by heating or low temperature roasting into a certain shape of the porous metal parts; high temperature sintering into a solid only metal parts of the composition, if necessary Can be appropriate post-processing metal powder injection molding advantages can be prepared complex shape, high accuracy parts of the parts, parts of the density and performance of the same, both isotropic.
Sintering density of up to 95% or more, excellent mechanical properties can be compared with the United States forging materials. Can be made of micro-composite materials or composite parts, give full play to the performance advantages of different materials. It is convenient to adopt a multi-cavity mold, high forming efficiency, long mold life, especially suitable for mass production. Disadvantages Due to the large number of thread shrinkage during the sintering process, the shrinkage rate is 11% ~ 20%, so the process produces tight products with limited tolerance. MIM process, including mixing, injection molding, degreasing, sintering, the dimensional accuracy of products by each process set the parameters of the nature of raw materials and processing conditions and mold design and other aspects of the impact, thus affecting the quality of products.