水蒸气温度对700℃先进超超临界锅炉候选合金GH2984氧化行为的影响  

Effect of Steam Temperature on Oxidation Behavior of GH2984 Alloy as a Candidate for 700℃ Advanced Ultra-supercritical Boilers

作　　者：杨珍[1] 鲁金涛[1] 张夏妮 赵新宝[1] 袁勇[1] 党莹樱[1] 尹宏飞[1] 谷月峰[1] YANG Zhen;LU Jin-tao;ZHANG Xia-ni;ZHAO Xin-bao;YUAN Y〇 ng;DANG Ying-ying;YIN H〇 ng-fei;GU Yue-feng(National Engineering Research Center of Clean Coal Combustion for Utility Boilers,Xi？an Thermal Power Research Institute Co.,Ltd.,X i？an 710032,China)

机构地区：[1]西安热工研究院有限公司电站清洁燃烧国家工程研究中心,西安710032

出　　处：《材料工程》2018年第1期74-82,共9页Journal of Materials Engineering

基　　金：国家自然科学基金项目(51401163,51301130)

摘　　要：采用X射线衍射仪、扫描电子显微镜对比研究GH2984合金在750℃和850℃纯水蒸气中的氧化行为。结果表明:GH2984合金的氧化动力学遵循抛物线规律;温度升高,Cr挥发加速,外氧化和内氧化的速率急剧增加,氧化膜的组成结构发生明显的变化。750℃时,合金表面形成单层致密的(Cr,Mn)_2O_3膜;温度升至850℃,氧化膜中空洞的数量大幅增加,氧化膜转变为由薄的外层Fe_2TiO_5和厚的次外层(Cr,Mn)_2O_3及薄的内层(Nb,Mo)_2O_5组成的三层结构。Ti,Al优先于晶界处发生内氧化,分别形成TiO_2和Al_2O_3;两种内氧化产物的尺寸和数量均随温度升高而增加。The oxidation behavior of GH2984 alloy in pure steam at 750℃ and 850℃ was investigated by using X-ray diffractometer(XRD)and scanning electron microscope equipped with energy dispersive spectra(SEM/EDS).Results show that GH2984 alloy is oxidized parabolically with time.The temperature rising greatly promotes the external and internal oxidation and also the evaporation of Cr.The composition and microstructure of the oxide films change obviously.At 750℃,a compact and single-layered(Cr,Mn)_2O_3 film is formed on alloy surface;the number of voids in oxide scale increases at 850℃,whereas a three-layered oxide scale consisting of thin Fe_2TiO_5 outer layer and much thicker(Cr,Mn)_2O_3 middle layer and thinner(Nb,Mo)_2O_5 inner layer is formed at the elevated temperature.Ti and Al are internally oxidized preferentially along grain boundaries to be TiO_2 and Al_2O_3,respectively;both the number and the size of the two internal oxides increase with the temperature rising.

关 键 词：GH2984高温合金 先进超超临界燃煤电站 水蒸气 高温氧化 

分 类 号：TG132.3[一般工业技术—材料科学与工程]