晶粒细化对Cu-20Ni-20Cr合金氧化行为的影响  

Effect of Grain Size on the Oxidation Behavior of Cu-20Ni-20Cr Alloy

作　　者：曹中秋[1,2] 牛焱[3] 吴维 

机构地区：[1]沈阳师范大学 [2]中国科学院金属研究所,辽宁沈阳110016 [3]中国科学院金属研究所

出　　处：《稀有金属材料与工程》2003年第12期1016-1020,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助项目(59871050和50071058)

摘　　要：为探讨晶粒尺寸变化对三元复相合金氧化行为的影响,采用机械合金化制备了纳米晶三元Cu-20Ni-20Cr合金,并对比研究了该合金与同成分的铸态合金在700℃～800℃,0.1MPa纯氧气中的氧化行为。结果表明,铸态合金表面没有形成连续的Cr2O3保护膜,而是形成了含有所有组元氧化物及它们复合氧化物的复杂氧化膜结构。纳米晶Cu-20Ni-20Cr合金在700℃时合金表面形成了连续的Cr2O3氧化膜,而800°C时虽没有形成Cr2O3外氧化膜,但氧化膜规则平坦,外层是CuO,中间层是Cu2O,NiO和Cr2O3组成的混合氧化物区,内层则形成了一薄但不连续的Cr2O3层。晶粒细化降低了合金表面形成Cr2O3氧化膜所需活泼组元Cr的临界浓度。In order to study the effect of grain size on the oxidation behavior of ternary multi-phase alloys, ternary Cu-20Ni-20Cr alloys were prepared at 700degreesC - 800degreesC in pure O-2 using are-melting(CA) and mechanical alloying(MA), respectively. The results show that for CA-Prepared Cu-20Ni-20Cr, no continue Cr2O3 film is formed on the surface of cast alloy, instead a complex oxidation films structure is formed made up of all the component oxides on the other hand with the fine-granular(nano-meter scale) MA-Prepared Cu-20Ni-2OCr alloy, oxidation at 700degreesC resulted in a film structure of 3 layers- (i) an outer CuO layer, (ii) an intermediate layer containing a mixture of Cu2O, NiO and Cr2O3, and (iii) an inner discontinuous Cr2O3 layer at 800degreesC no continuous Cr2O3 film forms on the surface. It is found that the finer grains reduced the critical concentration of the active element Cr suitable for the formation of Cr2O3 oxidation film on the alloy surface.

关 键 词：Cu-Ni-Cr合金 晶粒细化 复相组织 高温氧化 

分 类 号：TG115[金属学及工艺—物理冶金]