High-temperature Anti-oxidation Property of Al2O3Gradient Composite Coatings on TC11 Alloys

Affiliation of Author(s):材料科学与技术学院

Journal:Cailiao Daobao/Mater. Rev.

Abstract:Aiming at mitigating the high-temperature oxidation of titanium alloy which causes mechanical properties deterioration and lifetime reduction, a gradient composite coating composed of gradient alumina (ZrO2+Al2O3) and Al2O3via a sol-gel me-thod (with the advantage of ease of composition control) on the surface of TC11 titanium alloy. Experiment were carried out among gradient coating, Al2O3coating and matrix, and an oxidation rate of 0.015 mg2/ (cm4·h) and an oxidation index of 2.137 for the gradient coating were obtained from the fitting results of weight gain data after 700℃-100 h oxidation. It can be concluded that the high-temperature oxidation resistance of the gradient coating is better than the others taking into account weight gain curve and EDS analysis upon the oxidized samples. Thermal shock test at 700℃ confirms the better match of thermal expansion coefficient between matrix and Al2O3outer layer for gradient coating (ZrO2+Al2O3), inferring the mitigation effect due to the chemical composition gradient to the mismatch which further benefits the promotion of resistance toward high-temperature oxidation and lifetime prolongation of titanium alloy matrix. © 2017, Materials Review Magazine. All right reserved.

ISSN No.:1005-023X

Translation or Not:no

Date of Publication:2017-07-25

Co-author:Du, Wenbo,Tao, Xuewei,Luo, Xixi

Correspondence Author:Du, Wenbo,Yao Zhengjun

Date of Publication:2017-07-25