Abstract
The effects of sintering conditions and heat-treatment conditions on the mechanical properties of sintered tool steel(AISI D2)compacts were investigated. An AISI D2 gas atomized powder and polyamide binder were mixed well and injection molded into metallic molds for transverse test specimen. These injection-molded compacts were debound at 593 K and then sintered at various temperatures between 1473 K and 1483 K. The sintered compacts were annealed at 1173 K and quenched from 1293 K, and then were tempered at various temperatures between 453 K and 803 K. The relative density increased with increase in sintering temperature and showed to be more than 99 in the case of 1483 K. The hardness decreased with elevating the tempering temperature and showed to be larger than 58 HRC in the case of 543 K. The transverse rupture strength of the compacts sintered at 1473 K and 1478 K showed to be larger than 3000 MPa regardless the tempering temperatures. The tool steel compacts of which mechanical properties were equivalent to those of the wrought tool steels could be fabricated by controlling the sintering and heat-treatment conditions precisely.
