The Microstructure and Mechanical Properties of Heat Treated NiCr20TiAl Superalloy

Abstract:

NiCr20TiAl is a typical age-hardening superalloy with Ni-Cr as matrix and γ′ as strengthening phase. The microstructure and mechanical properties of nickel base superalloy NiCr20TiAl under different heat treatment were examined by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), optical microscope (OM) and mechanical tester. The results showed that superior comprehensive mechanical performance of NiCr20TiAl cast alloy was achieved by 1050°C/8h, air cool (AC) +700°C/16h, AC treatment. The edge cracks problem was resolved by 1150°C/1h, water quench (WQ) solid solution treatment before cold rolling process. The vickers hardness of the alloy decreases from 308 to 148. The vickers hardness of the NiCr20TiAl alloy could be controlled below 250 by 1080°C/2min treatment.

• Periodical: Materials Science Forum (Volume 849)
• Pages: 531-536
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.849.531
• Online since: March 2016
• Authors: Ran Wei*, Hui Yun Wu, Qing Quan Zhang, Ming Yang Li, Yu Cao, Zhen Rui Li
• Keywords: Mechanical Performance, Microstructure, NiCr20TiAl Nickel Base Superalloy

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