| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing: Processing Effects on Microstructure and Material Performance
|
| Presentation Title |
Effects of Post-heat Treatments on the Microstructure Evolutions, High Temperature Oxidation and Mechanical Properties of IN738LC Fabricated by Selective Laser Melting |
| Author(s) |
Kyu-Sik Kim, Myeong-Se Kim, Kee-Ahn Lee |
| On-Site Speaker (Planned) |
Kyu-Sik Kim |
| Abstract Scope |
Effects of different heat treatments on the microstructure evolution, oxidation behavior, and mechanical properties of additively manufactured IN738LC were studied. Three different post-heat-treatments were performed respectively: standard heat-treatments, direct aging, hot isostatic pressing. Changes in amounts of defects and microstructure characteristics were analyzed quantitively by OM, SEM, EBSD, and TEM. Oxidation behavior was investigated by high-temperature isothermal oxidation tests from 800 to 1100°C. The influence of microstructures on the oxidation mechanism is discussed in the perspective of local chemical-compositions. Mechanical properties were evaluated from room temperature up to 1000°C. As a result, the direct-aged sample showed the highest yield strength of 1170.3 MPa at room temperature. Interestingly, the serrated stress flow is observed only in the as-built sample due to a dynamic strain aging at intermediate temperatures. Deformed microstructures were analyzed to discuss the effects of post-heat-treatments on strengthening mechanisms and deformation behaviors of IN738LC fabricated by selective laser melting. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |