Abstract
The effects of powder characteristics on the microstructures and mechanical properties of sintered alloy tool steel (SKD11) compacts by metal injection molding were investigated. A gas-atomized(GA)and a water-atomized(WA)alloy tool steel powders and a polyamide binder were used. They were mixed well and injected into metallic molds for transverse test specimens. These injection-molded specimens were debound at 593 K in air and then were sintered at various temperatures between 1473 K and 1483 K in vacuum. These sintered compacts were heated at 1293 K and quenched, and then were tempered at various temperatures between 453 K and 803 K. The densification of the GA powder compact was fairly superior to that of the WA powder compacts. Consequently, the mechanical properties of the sintered GA powder compacts were superior to those of the sintered WA powder compacts. The mechanical properties equivalent to those of the wrought alloy tool steel could be fabricated successfully by controlling the sintering and heat-treatment conditions precisely.
