Hot corrosion behavior of NbSi2/SiO2-Nb2O5 multilayer coating on Nb alloy

被引：39

作者：

Ge, Yulin ^{[1
,2
]}

Wang, Yaming ^{[1
,2
]}

Chen, Junchen ^{[1
,2
]}

Zou, Yongchun ^{[1
,2
]}

Guo, Lixin ^{[1
,2
]}

Ouyang, Jiahu ^{[1
,2
]}

Jia, Dechang ^{[1
,2
]}

Zhou, Yu ^{[1
,2
]}

机构：

[1] Harbin Inst Technol, Inst Adv Ceram, Harbin 150001, Heilongjiang, Peoples R China

[2] Harbin Inst Technol, Key Lab Adv Struct Funct Integrat Mat & Green Mfg, Harbin 150001, Heilongjiang, Peoples R China

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2018年 / 767卷

关键词：

Nb alloy; Multilayer coating; Pack cementation; Microarc oxidation; Hot corrosion; ULTRAHIGH TEMPERATURE ALLOY; MICRO-ARC OXIDATION; SILICIDE DIFFUSION COATINGS; THERMAL BARRIER COATINGS; ELECTROLYTE CHEMISTRY; RESISTANCE; TI; NIOBIUM; MICROSTRUCTURE; SODIUM;

D O I：

10.1016/j.jallcom.2018.07.059

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A NbSi2/SiO2-Nb2O5 multilayer coating, consisting of a NbSi2 inner layer and a SiO2-Nb2O5 outer layer, was prepared on Nb alloy through halide activated pack cementation (HAPC) and microarc oxidation (MAO). The hot corrosion behaviors of the single NbSi2 coated and the NbSi2/SiO2-Nb2O5 coated Nb alloys were comparatively investigated with a mixture of Na2SO4/NaCl (3:1 wt.%) salt at 900 degrees C. The growth kinetics of the corroded scales follow the parabolic laws, and the parabolic rate constants of the NbSi2 coated and the NbSi2/SiO2-Nb2O5 coated specimens were 2.16 x 10(-3) mms(-2) and 1.04 x 10(-3) mms(-2), respectively. During the corroding process, the SiO2-Nb2O5 outer layer that serves as a barrier promotes the formation of continuous SiO2 scale, and isolates the NbSi2 layer from the corrosion salt. The lower corrosion rate of the NbSi2/SiO2-Nb2O5 coated specimens is attributed to the formation of the protective SiO2 corroded scale. (C) 2018 Elsevier B.V. All rights reserved.

引用

页码：7 / 15

页数：9

共 51 条

[11] Lanthanum hexaaluminate - a new material for atmospheric plasma spraying of advanced thermal barrier coatings [J].