Metal injection moulding of a 17-4 PH stainless steel: a comparative study of mechanical properties

While the metal injection moulding (MIM) of the precipitation-hardenable 17-4 PH stainless steel has found wide-ranging applications in a number of industries and popularity as a workhorse alloy, data on the as-sintered properties 'that can be expected' is limited and scattered in the literature. A quantitative comparison of the mechanical properties of as-sintered 17-4 PH materials prepared via MIM is currently not available in the literature. -5 mu m, -15 mu m, and -45 mu m starting 17-4 PH stainless steel powder materials and their bimodal mixtures were used to formulate with feedstocks investigated in this work. This paper compares the as-sintered mechanical properties resulting from the measured tensile tests against those properties reported in the literature, those specified in the ASTM and MPIF standard minimum specification for MIM materials, those properties specified in the material suppliers' datasheets and the mechanical properties of 17-4 PH wrought material - for completeness. While the as-sintered properties of the CSIR 17-4 PH material are generally lower than expected, the comparison shows that the measured properties are within the industry standard specifications. Findings from this study are a testament that a range of mechanical properties is feasible from the 17-4 PH alloy.