INFLUENCE OF RARE EARTH DOPING ON MECHANICAL PROPERTY AND MICRO-STRUCTURE OF CHROMIA OXIDE FILM

作     者：JIN Huiming FELIX Adriana 

作者机构：College of Mechanical Engineering Yangzhou University Yangzhou 225005 China College of Materials Engineenng National University of Antiuquia Medellin 23715 Colombia 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2008年第21卷第3期

页      面：16-19页

核心收录：

学科分类：08[工学] 080203[工学-机械设计及理论] 0802[工学-机械工程] 

基　　金：National Natural Science Foundation of China(No.29231011) Natural Science Foundation of Jiangsu Province,China(No.07KJD430246) 

主　　题：Stress Acoustic emission Interface Yttrium Oxidation 

摘      要：The isothermal oxidizing kinetics of Co-40Cr alloy and its yttrium ion-implanted samples are studied at 1 000 ℃ in air by thermal-gravity analysis （TGA）. Scanning electronic microscopy （SEM） is used to examine the Cr2O3 oxide film＇s morphology after oxidation. Acoustic emission （AE） method is used in situ for monitoring the cracking and spalling of oxide films formed on both samples during oxidizing and subsequent air-cooling stages. Theoretical model is proposed relating to the film fracture process and is used for analyzing the acoustic emission spectrum both on time domain and on AE-event number domain. It is found that yttrium implantation remarkably reduces the isothermal oxidizing rate of Co-40Cr and improves the anti-cracking and anti-spalling properties of Cr2O3 oxide film. The reasons for the improvement are mainly that the implanted yttrium reduced the grain size of Cr2O3 oxide, increased the high temperature plasticity of oxide film, and remarkably reduced the number and size of Cr2O3/Co-40Cr inteffacial defects.