Effects of Dy on Transient Oxidation Behavior of EB-PVD β-NiAl Coatings at Elevated Temperatures  

作　　者：ZHAO Xiaoyu GUO Hongbo GAO Yuzhi WANG Shixing GONG Shengkai 

机构地区：[1]School of Materials Science and Engineering, Beihang University, Beijing 100191, China

出　　处：《Chinese Journal of Aeronautics》2011年第3期363-368,共6页中国航空学报（英文版）

基　　金：National Natural Science Foundation of China （50771009, 50731001）; National Basic Research Program of China （2010CB631200）; Research Fund for the Doctoral Program of Higher Education of China （20070006017）

摘　　要：β-NiAl is a potential oxidation-resistant coating material to be operated at temperatures above 1 150 ℃. In this paper,β-NiAl coatings with 0-0.5 at% Dy are prepared by electron beam physical vapor deposition （EB-PVD）. Transient oxidation behavior of the coatings is investigated. At 1 200 ℃, only stable α-Al2O3 phase is observed on the 0.05 at% doped coating, whereas the phase transfomlation from θ-Al2O3 to α-Al2O3 occurs in the 0.5 at% Dy doped coating during 1 h oxidation. At 1 100 ℃, all the coatings reveal the transient transformation of θ-α in the early 15 min and the transformation for the 0.05 at% Dy doped coating is completed within 45 min, much earlier than that for the 0.5 at% Dy doped coating. Overdoping of Dy retards the transformation of θ-α. The undoped and overdoped coatings reveal the whisker structure of θ-Al2O3 even after 20 h oxidation at 1 100 ℃, while the 0.05 at% Dy coating reveals typical granulated structure of α-Al2O3.β-NiAl is a potential oxidation-resistant coating material to be operated at temperatures above 1 150 ℃. In this paper,β-NiAl coatings with 0-0.5 at% Dy are prepared by electron beam physical vapor deposition （EB-PVD）. Transient oxidation behavior of the coatings is investigated. At 1 200 ℃, only stable α-Al2O3 phase is observed on the 0.05 at% doped coating, whereas the phase transfomlation from θ-Al2O3 to α-Al2O3 occurs in the 0.5 at% Dy doped coating during 1 h oxidation. At 1 100 ℃, all the coatings reveal the transient transformation of θ-α in the early 15 min and the transformation for the 0.05 at% Dy doped coating is completed within 45 min, much earlier than that for the 0.5 at% Dy doped coating. Overdoping of Dy retards the transformation of θ-α. The undoped and overdoped coatings reveal the whisker structure of θ-Al2O3 even after 20 h oxidation at 1 100 ℃, while the 0.05 at% Dy coating reveals typical granulated structure of α-Al2O3.

关 键 词：Β-NIAL OXIDATION phase transformation reactive element electron beam physical vapor deposition （EB-PVD） 

分 类 号：TG174.444[金属学及工艺—金属表面处理] TB332[金属学及工艺—金属学]