Infrared Brazing of CoCrFeMnNi Equiatomic High Entropy Alloy Using Nickel-Based Braze Alloys

Entropy

Shyi-Kaan Wu¹  Chieh Lin¹  Ren-Kae Shiue¹  Huai-Li Huang² 

[1] Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan;Department of Mechanical Engineering, National Taiwan University, Taipei 106, Taiwan;

关键词: high entropy materials;    infrared brazing;    nickel-based filler metal;    microstructure;   

DOI  :  10.3390/e21030283

来源: DOAJ

【 摘 要 】

Infrared vacuum brazing of CoCrFeMnNi high entropy alloy (HEA) using BNi-2 and MBF601 fillers has been investigated. Both brazes show poor wettability at temperatures only 20 °C above their liquidus temperatures. However, the wettability of BNi-2 and MBF601 fillers on CoCrFeMnNi HEA is greatly improved with increasing the test temperatures, 50 °C above their liquidus temperatures. The BNi-2 brazed joints are dominated by Ni-rich matrix with huge CrB and a few tiny boride precipitates. Average shear strengths of joints increase with increasing brazing temperature and/or time, and fracture location changes from blocky CrB in the brazed zone to grain boundary boride in the substrate. The MBF601 brazed joints are composed of CoCrFeMnNi-based matrix, particles of B/Co/Cr/Fe/Mn/Ni/P compounds, and some phosphides form along the grain boundaries of the substrate. The specimen brazed with MBF601 filler foil at 1050 °C for 600 s has the highest average shear strength of 321 MPa, while that brazed at 1080 °C for 600 s has a lower average shear strength of 271 MPa due to the presence of solidification shrinkage voids.

【 授权许可】

Unknown