Microstructures and Hardening Mechanisms of a 316L Stainless Steel/Inconel 718 Interface Additively Manufactured by Multi-Material Selective Laser Melting
Shahir Mohd Yusuf,
Nurainaa Mazlan,
Nur Hidayah Musa,
Xiao Zhao,
Ying Chen,
Shoufeng Yang,
Nur Azmah Nordin,
Saiful Amri Mazlan,
Nong Gao
Affiliations
Shahir Mohd Yusuf
Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
Nurainaa Mazlan
Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
Nur Hidayah Musa
Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
Xiao Zhao
Aeronautical and Astronautical Department Southampton Boldrewood Innovation Campus, University of Southampton, Southampton SO16 7QF, UK
Ying Chen
Fujian Provincial Key Laboratory of Functional Materials and Applications, Xiamen University of Technology, Xiamen 361024, China
Shoufeng Yang
Production Engineering, Machine Design and Automation Section, Department of Mechanical Engineering, Katholieke Universiteit Leuven (KU Leuven), 3001 Leuven, Belgium
Nur Azmah Nordin
Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
Saiful Amri Mazlan
Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
Nong Gao
Materials Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
For the first time, the interfacial microstructures and hardening mechanisms of a multi-material (MM) 316L stainless steel/Inconel 718 (316L SS/IN 718) interface fabricated by a novel multi-material selective laser melting (MM SLM) additive manufacturing (AM) system have been investigated in this study. MM 316L SS/IN 718 parts were successfully built with high densification levels (>99%) and low porosity content (average: ~0.81%). Microscopy analysis indicates that the interfacial microstructures are characterised by dense dislocation tangling networks, NbC and TiC, and very small amounts of Laves phase (<2 wt. %). In addition, equiaxed grains (average: 45 ± 3 μm) are attained in the interfacial region, whereas both individual IN 718 and 316L SS regions exhibit show columnar grains with average sizes of 55 ± 5 μm and 85 ± 3 μm, respectively. Vickers microhardness (HV) and nanoindentation measurements exhibit that the hardness values of the interfacial region are between those of the individual material regions. A strengthening model is built to assess the contribution of intrinsic strength, solid solution, precipitations, dislocations, and grain boundaries to the overall interfacial hardness of the as-built MM alloy.
