Influence of hot isostatic pressing on the properties of 316L stainless steel, Al-Mg-Sc-Zr alloy, titanium and Ti6Al4V cold spray deposits

Abstract

In this paper an effect of capsule-free hot isostatic pressing (HIP) on the porosity and mechanical properties of different cold spray deposits was experimentally evaluated. The HIP post-treatment significantly decreased (more than 2 times) the porosity of 316L and pure titanium deposits. The densification effect of HIP on the porous Ti6Al4V deposit was significantly less pronounced. Mechanical properties of the deposits after HIP were also improved. In particular, the tensile strength of the stainless steel, pure titanium and Ti6AL4V increased from 30 MPa, 70 MPa and 20 MPa to 211 MPa, 480 MPA and 560 MPa correspondingly. Compressive strength of the Al-Mg-Sc-Zr alloy samples after HIP was also increased ~25%. Improvement of mechanical properties is explained by material diffusion and microstructure changes during HIP cycle.