Powder material compression molding is to fill a mixture of a certain mass (volume) of alloy powder, inorganic non-metal powder and a certain forming agent into a rigid mold cavity, and then apply a certain size to the powder along a single axial direction through upper and lower dies. Pressure is a process in which the loose powder is compressed into a compact with a certain size, shape, density and strength in a closed cavity, and then the compact is ejected from the mold. The whole process includes three steps of powder loading, pressing and demoulding.
The basic purpose of compression molding is to compact the loose powder body into a semi-finished compact with a certain size, shape, density and strength, and lay the foundation for the next step of sintering. Generally speaking, in the pressing process, it is relatively easy to achieve a certain size, shape and average density, but it is more difficult to make the density distribution of the green compact uniform. The more complex the shape, the more difficult it is to make the green compact density distribution uniform. The inhomogeneity of the density distribution of the green compact not only ultimately affects the mechanical properties of the product, but is also an important cause of compaction waste such as cracking, delamination, edge drop, uneven sintering shrinkage, product deformation, and out-of-accuracy.
热门资讯
