Development of 316L and 316L-1.0Y2O3 ODS steel fabricated by selective laser melting (SLM)

• Main Author: Zhou, Chong
• Other Authors: Zhou Wei
• Format: Theses and Dissertations
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/77043
• Institution: Nanyang Technological University

Oxide dispersion strengthened (ODS) ferritic steels contain a high density of thermally stable nanoscopic Y (Al, Ti) oxides particles, leading to exhibit superior physical and mechanical properties, but the conventional manufacturing route based on powder metallurgy (PM) is unfavorable. Selective laser melting (SLM) is an excellent additive manufacturing (AM) technology with outstanding potential, which has been regarded as a candidate for processing ODS alloys. And 316L stainless steel is one of the most widely investigate materials for SLM due to a wide range of applications. In this work, Y2O3 particles were used to add into 316L stainless steel by using the SLM process to explore the differences between 316L and 316L - 1.0 Y2O3 in the porosity, microstructure, and micro-hardness. The porosity of 316L - 1.0 Y2O3 is significantly higher than 316L. And both the molten pool and austenitic columnar grain could be observed in 316L and 316L - 1.0 Y2O3 steel by an optical microscope and a scanning electron microscope. While 316L - 1.0 Y2O3 appeared many lack of fusion regions and spherical pores, leading to an unobvious increase in microhardness. In conclusion, Y2O3 particles have a significant influence on the porosity, microstructure, and microhardness of 316L stainless steel fabricated by SLM, which is worthy of further research.