Microstructure Characterization of Ni-Based Alloys for Packaging Application upon Long-Term Heat Treatment

Coatings

Jianbing Ren¹  Kejian Li²  Yilong Ma² 

[1] School of Mechanical and Power Engineering, Chongqing University of Science & Technology, Chongqing 401331, China;School of Metallurgy and Materials Engineering, Chongqing University of Science & Technology, Chongqing 401331, China;

关键词: Ni alloy;    Mo addition;    grain size;    precipitate;    heat treatment;   

DOI  :  10.3390/coatings11101159

来源: DOAJ

【 摘 要 】

In this study, an investigation was conducted to examine two types of Ni-based alloys upon long-term heat treatment and compare their grains, surface corrosion layers and microhardness values. The working environment of the tested samples was a temperature of 1000 °C for 5000 h. Two samples, respectively, contained low (~8 wt.%) and high (~16 wt.%) contents of Mo, and the low-Mo-content sample contained Nb (~4 wt.%) and other elements. The grains, precipitates, corrosion layers and microhardness values of the samples before and after heat treatment were determined by scanning electron microscopy, electron back-scattered diffraction, transmission electron microscopy, X-ray diffraction analysis and Vickers hardness tests. The results revealed that the grain was surprisingly stable in the sample with the higher Mo content; after heat treatment, the grain size was ~35 μm, which was similar to the grain size before heat treatment. Moreover, for the sample with the higher Mo content, the microhardness was found to be higher, especially after long-term high-temperature treatment, which is of great significance for the long service life of materials.

【 授权许可】

Unknown