Revealing the impact of Hot Isostatic Pressing temperature on the microstructure and mechanical characteristics of Selective Laser Melted CuAlNiMn shape memory alloy

Abstract

The present research examines the impact of temperature during Hot Isostatic Pressing (HIP) on the mechanical, microstructure, and density characteristics of Cu-based shape memory alloys (SMAs) made by Selective Laser Melting (SLM). HIP improved the density of the built components by 11.5 %, with a reduction in density with an increase in HIP temperature. Pore aspect ratio analysis revealed non-spherical pores at higher temperatures, while spherical and small pores were observed at 950 °C. SEM analysis demonstrated the disappearance of shrinkage porosity and an increase in grain size with higher HIP temperatures. XRD analysis confirmed phase transformation and variation in crystallite size with an increase in HIP temperature. After HIP treatment, microhardness and tensile strength significantly improved, with the 950 °C sample showing the highest values.