Journal Article

Hot isostatic pressing influence on the mechanical properties of selectively laser-melted 316L steel

Grzelak, K., Torzewski, J., Kania, B., Kluczyński, J., Gocman, K., Szachogłuchowicz, I., Śnieżek, L., Wachowski, M., Perkowski, K., Oziębło, A.

2020

Overview

Industries that rely on additive manufacturing of metallic parts, especially biomedical companies, require material science-based knowledge of how process parameters and methods affect the properties of manufactured elements, but such phenomena are incompletely understood. In this study, we investigated the influence of selective laser melting (SLM) process parameters and additional heat treatment on mechanical properties. The research included structural analysis of residual stress, microstructure, and scleronomic hardness in low-depth measurements. Tensile tests with specimen deformation analysis using digital image correlation (DIC) were performed as well. Experiment results showed it was possible to observe the porosity growth mechanism and its influence on the material strength. Specimens manufactured with 20% lower energy density had almost half the elongation, which was directly connected with the porosity growth during energy density reduction. Hot isostatic pressing (HIP) treatment allowed for a significant reduction of porosity and helped achieve properties similar to specimens manufactured using different levels of energy density.

• Publisher: Polish Academy of Sciences
• Subject: 316l austenitic steel / Biomedical materials / Deformation analysis / Digital imaging / Elongation / Flux density / Heat treating / Heat treatment / Hot isostatic pressing / Laser beam melting / Mechanical properties / microscopic investigation / Porosity / Process parameters / Residual stress / residual stresses / selective laser melting (slm) / Structural analysis / Tensile tests