925镍铁基耐蚀合金均匀化及高温氧化行为  

Oxidation Behavior during High Temperature Homogenization Treatment of Cast Ni-Fe Based Corrosion Resistant 925 Alloy

作　　者：赵展[1] 李景阳[1] 董建新[1] 姚志浩[1] 张麦仓[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《中国腐蚀与防护学报》2017年第1期1-8,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(51571012)~~

摘　　要：采用氧化增重实验、XRD、SEM以及EDS研究了925合金在均匀化温度1130~1190℃时的高温氧化行为。结果表明,925合金完全均匀化需要在1160℃保温20 h以上。均匀化中形成的氧化膜由内至外分为3层,分别为TiO_2层、Cr_2O_3层以及由TiO_2和尖晶石结构的Cr、Fe氧化物构成的外层。均匀化时间超过20 h,Cr_2O_3层开始减薄,并且尖晶石状Cr、Fe氧化物部分剥落;氧化时间增加至50 h时,Cr_2O_3氧化层减薄,尖晶石状Cr、Fe大量剥落。同时内部大量形成Al、Ti内氧化物。综合考虑氧化行为对合金的影响,在满足合金均匀化要求的前提下,建议925合金的均匀化工艺为1160℃保温20 h。The oxidation behavior of the as-cast 925 superalloy were investigated in the temperature range of 1130-1190 ℃ by means of mass change measurement, X-ray diffractometer, scanning electron microscopy and energy dispersive X-ray spectroscopy. The results show that after homogenization treatment at 1160℃ for 20 h, the formed oxide-scale showed three-layered structure： an internal oxidation layer composed of Al2O3 and TiO2, a continuous and dense middle layer of Cr2O3 and an outmost layer of the spinel oxidation of Cr and Fe. When the homogenization time increased, the layer of Cr2O3 became thinner and the spinel oxides of Cr and Fe begun to break down and the oxidation was aggravated. Taking the oxidation behavior of the alloy during homogenization into account, the appropriate homogenization of 925 superalloy should be conducted at 1160℃ for 20 h.

关 键 词：925合金 均匀化 高温氧化 

分 类 号：TG146[一般工业技术—材料科学与工程]