摘要
用直流反应溅射方法在镍基高温合金K38G上制备了Al_2O_3涂层,研究了涂覆(Na、K)_2SO_4的试样在1123K空气中的热腐蚀行为。实验表明,Al_2O_3涂层具有良好的粘附性,能降低K38G合金的腐蚀速率并减小腐蚀深度。本文还讨论了Al_2O_3涂层对K38G热腐蚀影响的机制。
Hot corrosion behavior of Ni-base superalloy K38G with Al_2O_3 coating was investigated in air at 1123K by applying (Na,K)_2SO_4 salt deposit. The Al_2O_3 coating was prepared by means of DC reactive sputtering, which improved the corrossion resistance of superalloy K38G. Both the basic fluxing and the oxidation-sulfidation occurred during the incubation period of the uncoated specimensm whereas they were alleviated by the application of the Al_2O_3 coating. For example, the depth of internal salfidation layer was minimized 3 times. It was also observed that the Al_2O_3 coating was scarcely thinned during corrosion. Some (Al,Cr)_2O_3 pillars and the TiO_2 needles were found at the coating / salt interface for the coated specimen. The mechanisms of the influence of the Al_2O_3 coating on hot corrosion of K38G alloy was discussed.
出处
《腐蚀科学与防护技术》
CAS
CSCD
1993年第1期32-37,共6页
Corrosion Science and Protection Technology
基金
国家自然科学青年基金
关键词
热腐蚀
耐热合金
氧化铝
涂层
Al_2O_3 coating
hot corrosion
superalloy
