[T10] Other Processing

[16P-T10-03] Impact of Sintering Parameters on Sintering Densification and Mechanical Properties of High-Performance Powder Metallurgy (HPM) 17-4PH Compacts

X. Huang¹, *H. Wang¹, T. Yang², Y. Lan¹, Y. Fan³, G. Shu^1,2 (1.Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taiwan, 2.Institute of Mineral Resources Engineering, National Taipei University of Technology, Taiwan, 3.United Powder Technologies (UPT) Co., Ltd., Taiwan)

Keywords:17-4PH, high-performance powder metallurgy (HPM), sintering parameter, phase diagram, mechanical properties

Traditional press-and-sinter (PS) processes often use coarse 17-4PH stainless steel powders, resulting in low sintered density and poor mechanical properties. To address these issues, we developed a High performance Powder Metallurgy (HPM) process Using fine 17-4PH powders commonly used in metal injection molding (MIM) into PS process. Experimental results of sintering temperatures revealed that temperatures exceeding 1260°C induce δ-phase formation, enhancing diffusion rates, promoting pore spheroidization, and inhibiting grain coarsening. Sintering at 1320°C for an hour in H2 atmosphere yielded high-density (7.4 g/cm³) 17-4PH components with excellent mechanical properties (tensile strength approximately 1000 MPa, HRC 34 hardness, ~8% elongation). Temperatures exceeding 1360°C resulted in liquid phase formation, uneven alloy distribution, and grain coarsening. Our study underscores the cost-effective HPM process's ability to achieve mechanical properties comparable to MIM, enhancing competitive advantage in powder metallurgy technology.