Abstract
The effect of sintering conditions on the mechanical properties of SUS304L stainless steel sintered powder made by injection moldings has been studied. Specimens were made of SUS304L with 9μm in average diameter which was sintered at temperatures of 1573 K to 1673 K with the holding period of 1.8 ks to 14.4 ks in vacua of 1 Pa, then they were cooled in evacuated or nitrogen gas atmosphere. The higher the sintering temperature, and the longer the holding period at the elevated temperature, the greater the density of the sintered specimen. An example of this was greater than 98%. Specimens cooled in vacua gave the tensile strength of 520 MPa and the maximum hardness was given at the sintering temperature of 1623 K, regardless of the holding period. The mechanical strength of a sintered SUS304L specimen cooled in vacua was comparable with a specimen which was melted and cast. The specimens cooled in nitrogen gas yielded higher strengths and hardnesses possibly due to the nitride formation on the surface.
