K444合金表面CVD铝化物涂层的高温氧化和固态Na_(2)SO_(4)诱导的空气腐蚀  

High Temperature Oxidation and Solid Na_(2)SO_(4)Induced Corrosion of CVD Aluminide Coating on K444 Alloy in Air

作　　者：刘姝妤 耿树江[1] 王金龙[1] 王福会[1] 孙清云 吴勇 段海涛 夏思瑶 夏春怀 LIU Shuyu;GENG Shujiang;WANG Jinlong;WANG Fuhui;SUN Qingyun;WU Yong;DUAN Haitao;XIA Siyao;XIA Chunhuai(Shenyang National Laboratory for Materials Science,Northeastern University,Shenyang 110819,China;Wuhan Research Institute of Materials Protection,Wuhan 430030,China)

机构地区：[1]东北大学、沈阳材料科学国家研究中心东北大学联合研究分部,沈阳110819 [2]武汉材料保护研究所有限公司,武汉430030

出　　处：《中国腐蚀与防护学报》2023年第3期553-560,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家重点研发计划(2020YFB2010404);湖北省重点研发计划(2021BAA210)。

摘　　要：采用化学气相沉积(CVD)技术在镍基高温合金K444表面制备了渗铝涂层,对比研究了K444合金及其CVD渗铝涂层在不同温度下(750、850和950℃)的高温氧化行为和750℃-Na_(2)SO_(4)+Air条件下的腐蚀行为,获得了氧化和腐蚀动力学。利用SEM/EDS和XRD对氧化和腐蚀后的表面膜截面形貌和组成进行了观察和分析。结果表明,CVD渗铝涂层氧化及腐蚀时表面均能生成连续致密的Al2O3薄膜,抑制了金属元素的外扩散,减缓了氧化反应和与固态Na_(2)SO_(4)的反应,显著提升了K444合金的抗氧化能力和750℃下抗固态Na_(2)SO_(4)腐蚀的能力。Aluminide coating was prepared on Ni-base superalloy K444 by chemical vapor deposition(CVD).The oxidation behavior in air at 750,850 and 950℃,and solid Na_(2)SO_(4)induced corrosion in air at 750℃were investigated for K444 alloys without and with CVD aluminide coating respectively.The kinetic curves were obtained.The cross-section morphology and composition of oxidized and corroded samples were characterized by SEM/EDS and XRD.The results show that a continuous and dense Al2O3 scale can form on the surface of CVD aluminide coating during oxidation and corrosion,which inhibits the outward diffusion of metal elements,correspondingly,slows down the oxidation reaction and solid Na_(2)SO_(4)induced corrosion,and therefore,significantly enhances the resistance to the high temperature oxidation in air at 750-950℃,as well as to the solid deposits of Na_(2)SO_(4)induced corrosion in air at 750℃of K444 alloy.

关 键 词：镍基高温合金 CVD渗铝涂层 高温氧化 固态Na_(2)SO_(4)腐蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]