Single-step aging treatment for a precipitation-strengthened Ni-based alloy and its influence on high-temperature mechanical behavior

SCRIPTA MATERIALIA

卷:162

Article

Unocic, Kinga A.¹  Shin, Dongwon¹  Sang, Xiahan²  Cakmak, Ercan¹  Tortorelli, Peter F.¹ 

[1] Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN 37831 USA

[2] Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA

关键词: Ni-base alloys;    Grain boundaries;    Ni3Al;    Aging treatment;    Scanning transmission electron microscopy (STEM);    Carbides;   

DOI  :  10.1016/j.scriptamat.2018.11.045

来源: Elsevier

【 摘 要 】

A simplified aging treatment yielded microstructural features in Ni-based alloy that produced strengthening behavior normally associated with more complex thermal processing. Specifically, a time series of 800 degrees C heat treatments was used to study the evolution of grain boundary carbides and gamma' precipitates and the corresponding hardness, tensile strength, and creep resistance. These analyses and computational thermodynamic calculations revealed that a 4-hour aging treatment produced appropriately sized and uniformly distributed coherent gamma' precipitates and the desired Cr-rich carbides like those formed during the conventional two-step heat treatment. Accordingly, the former heat treatment produced targeted typical strength levels for this alloy. Published by Elsevier Ltd on behalf of Acta Materialia Inc.

【 授权许可】

Free