Spalling resistance of thermally grown oxide based on NiCoCrAlY(Ti) with different oxide peg sizes  

作　　者：Liang Yang Ryutan Choi Yu Zheng Mohammad Hassan Shirani Bidabadi Abdul Rehman Chi Zhang Hao Chen Zhi-Gang Yang 

机构地区：[1]Key Laboratory for Advanced Materials of Ministry of Education,Department of Materials Science and Engineering,Tsinghua University,Beijing 100084,China [2]Department of Defect Control,Samsung Electronics,Gyeonggi-do 18448,South Korea

出　　处：《Rare Metals》2021年第3期663-670,共8页稀有金属（英文版）

基　　金：financially supported by the Tsinghua University Initiative Scientific Research Program and the National Magnetic Confinement Fusion Energy Research Project of China(No.2015GB118001)。

摘　　要：NiCoCrAlY is usually used as the material to bond-coat in thermal barrier coating systems under high temperatures.Using NiCoCrAlY and adding different amounts of the active element Ti(0,0.1,0.3,and0.5;wt%),the relationship between oxide peg size and thermally grown oxide spalling resistance is ascertained by examining specimens subjected to a cyclic oxidation experiment.Oxide pegs,consisting of a Y-and Ti-rich oxide core and an outer Al_(2) O_(3) sheath,are formed by Ti and A1 successively reacting with oxygen after the rapid generation of Y-rich oxide.The size of the oxide pegs with higher Ti concentrations is on average bigger in the alloy.Severe thermally grown oxide spalling occurred in the0.5 wt% Ti specimen,but in the 0.3 wt% Ti specimen,it displayed the best adherence with the alloy due to the presence of fine pegs.Cavities existed at the interface between the inner oxide core and outer Al_(2) O_(3) sheath of larger pegs serve as microcrack sources and further induce severe scale failure combined with the initial interface crack between the scale and alloy.

关 键 词：Alloy Thermal cycling OXIDATION PEG 

分 类 号：TG174.4[金属学及工艺—金属表面处理]