摘要
研究了 3种不同Co含量双相Cu Co合金在 60 0～ 80 0℃空气中的氧化行为 .合金氧化动力学遵循抛物线规律 ,并且在同一温度下抛物线速率常数随Co含量升高而降低 .所有合金均形成由Cu和Co氧化物的复杂混合物组成的复合氧化膜 ,其中Cu的氧化物倾向于集中在膜的外层 .通常在外层膜下 ,是Co的氧化物和金属Cu的混合区 ;对于Co含量低于 50 % (质量分数 ,下同 )的合金 ,这就是Co的内氧化区 ;而对含 75 %Co的合金则是在Co氧化物的基体上分布着孤立的Cu颗粒 .与固溶体二元合金不同的是 ,在这一区域下面的合金基体没出现Co的贫化 .基于合金显微组织的双相特征 ,对合金氧化膜的特殊结构进行讨论 .
The air oxidation of three two\|phase Cu\|Co alloys namely Co\|25%, 50% and 75% Cu was studied at 600～800℃. The scaling kinetics follows only approximately the parabolic rate law, with rate constants isothermally increasing with the Cu content. All the alloys form composite scales containing complex mixtures of Cu and Co oxides, where Cu concentrates preferentially in the external regions. Beneath the external scales there is in most cases a region of a mixed Co oxide and Cu metal: for alloys containing up to 50% Cu this zone corresponds to the internal oxidation of Co, while for the alloy containing 25% Cu it is a Co oxide matrix containing dispersion of isolated Cu particles. At variance with the behavior of solid\|solution binary alloys, Co is not depleted in the alloy beneath this region in spite of its preferential local oxidation. The peculiar structure of the scales formed on these alloys is interpreted by considering their two\|phase nature.
出处
《腐蚀科学与防护技术》
CAS
CSCD
2000年第2期77-81,共5页
Corrosion Science and Protection Technology
基金
国家自然科学基金!资助 (No .5972 510 1和No.598710 50 )
