| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
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| Symposium
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Advancing Current and State-of-the-Art Application of Ni- and Co-based Superalloys
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| Presentation Title |
G-7: The Role of Microstructural Homogenization on Tensile and Stress-rupture Behavior of Selective Laser Melted Nickel Based 718 Alloy |
| Author(s) |
Shahzad Salam, Ichiro Mitama, Takuma Sakata |
| On-Site Speaker (Planned) |
Ichiro Mitama |
| Abstract Scope |
The effects of homogenization and HIP treatment on tensile and stress-rupture properties of selective laser melted 718 alloy were investigated. Samples were homogenized at 1065°C/4h or 1140°C/4h prior to industrial solution (982°C/1h) and double aging treatment (718°C/8h+621°C/8h) specified in AMS5663. Additional samples were subjected to hot-isostatic-pressing (HIP) at 1065°C/4h or 1140°C/4h under uniform stress of 100MPa prior to solution and aging. Tensile properties were determined at 25°C and 649°C in air, and stress-rupture tests were conducted at 649°C under a constant stress of 689MPa. Specimen without homogenization/HIP treatment exhibited inferior high-temperature ductility and rupture-life. Ductility improved significantly with homogenization/HIP treatments in both horizontal and vertical orientations due to grain recrystallization and interdendritic δ-phase dissolution. Specimen homogenized/HIP treated at 1140°C/4h exceeded the minimum high-temperature tensile requirements specified in AMS5663. Although the rupture-life also improved by homogenization/HIP treatments, minimum requirement of 23h of rupture life was not realized. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |