About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
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Symposium
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Additive Manufacturing of Metals: Microstructure, Properties and Alloy Development
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Presentation Title |
Cryogenic Mechanical Properties of CrCoNi Medium Entropy Alloy Produced by Selective Laser Melting with Hot Isostatic Pressing |
Author(s) |
Tri Hoang Nguyen, Minh Tien Tran, Kyung-Hwan Jung, Ho Won Lee, Sun-Kwang Hwang, Dong-Kyu Kim |
On-Site Speaker (Planned) |
Tri Hoang Nguyen |
Abstract Scope |
The present study investigated the mechanical properties and microstructure of CrCoNi medium entropy alloy (MEA) fabricated by selective laser melting (SLM) with hot isostatic pressing (HIP). The microstructure-property correlation of as-built and HIP treated CrCoNi MEA-SLM were examined by uniaxial tensile test, electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM) at room (298 K) and cryogenic (77 K) temperatures. The use of HIP significantly enhances the elongation to fracture at both temperatures compared to the as-built one. At 77 K, both yield strength, ultimate tensile strength, and elongation are substantially increased. The formation of nano-twinning at 77 K examined by TEM results in the increased tensile properties compared to room temperature. Furthermore, the steady work hardening behavior, which postpones the onset of necking instability, is attributed to the interaction between dislocations and twinning. It reveals that the CrCoNi MEA-SLM with HIP possesses the excellent mechanical properties at cryogenic temperature. |