摘要
研究了Co-20Re-25Cr-1Si-1Al合金在1000~1300℃下、0.1 MPa纯O_(2)气氛中、24 h的恒温氧化行为。实验结果表明,由于Re元素极易形成金属氧化物(ReO_(3))并从合金中逸出,导致合金在1000℃、1200℃和1300℃下出现了失重的现象。在1100℃条件下,连续Cr_(2)O_(3)保护层形成对合金起到保护作用,合金呈现出增重现象。在四个温度下的氧化膜均包含双层结构:外层氧化膜主要为CoO和CoCr_(2)O_(4),内层氧化膜为Cr_(2)O_(3)。1%Si和1%Al不足以使Co-20Re-25Cr-1Si-1Al合金发生Si和Al选择性外氧化,氧化膜下方发生Si和Al的内氧化。但1%Al的添加促进了Cr_(2)O_(3)氧化膜的形成,使得Co-20Re-25Cr-1Si-1Al合金的耐高温氧化性能大幅提高。
The constant temperature oxidation behavior of Co-20Re-25Cr-1Si-1 Al alloy was studied at 1000 ~1300 ℃ in a pure O_(2) atmosphere at 0.1 MPa for 24 h.The oxidation behavior of Co-20Re-25Cr-1Si-1Al alloy was investigated.The experimental results showed that the alloy showed weight loss at 1000 ℃,1200 ℃ and 1300 ℃ due to the ease of elemental Re-forming metal oxides(ReO_(3)) and escaping from the alloy.At 1100 ℃,the alloy show weight gain due to the formation of a continuous Cr_(2)O_(3) protective layer that protects the alloy.The oxide films at all four temperatures contain a bilayer structure:the outer oxide film was mainly CoO and CoCr_(2)O_(4),the inner oxide film was Cr_(2)O_(3).1% Si and 1% Al are not sufficient to cause selective external oxidation of Si and Al in Co-20Re-25Cr-1Si-1Al alloy,and internal oxidation of Si and Al occurr below the oxide film.However,the addition of 1% Al promotes the formation of Cr_(2)O_(3) oxide film,which greatly improves the high temperature oxidation resistance of Co-20Re-25Cr-1Si-1Al alloy.
作者
张帅
肖伯涛
Zhang Shuai;Xiao Botao(School of Materials and Mechatronics,Jiangxi Science&Technology Normal University,Nanchang 330038,Jiangxi,P.R.China;Jiangxi Key Laboratory of Surface Engineering,Nanchang 330038,Jiangxi,P.R.China)
出处
《江西科技师范大学学报》
2021年第6期30-34,共5页
Journal of Jiangxi Science & Technology Normal University
基金
国家自然科学基金项目(51865014)
材料成形与模具技术国家重点实验室开放基金项目(P2019-012)
江西科技师范大学硕士研究生创新专项资金项目(YC2019-X04)。
