摘要
针对Inconel 600和Inconel 690合金在高温高压水环境中生成的腐蚀氧化膜,提出了扩散路径分析模型,阐明了氧化膜微观结构及其形成机理。基于氧化膜成分、合金成分、以及环境因素,构建了Inconel 600及Inconel 690合金的Ni-Cr-H_2O三元相图。Inconel 600合金高温高压水腐蚀的扩散路径表明,其氧化膜由内层Cr_2O_3与外层FeCr_2O_4尖晶石构成。通过Inconel 690合金高温高压水腐蚀的扩散路径分析可知,氧化膜由单一的Cr_2O_3构成。扩散路径分析结果表明,在Inconel 600氧化膜中,O^(2-)比Cr^(3+)具有更高的扩散速率,而在Inconel 690氧化膜中,O^(2-)的迁移率较低,所受阻力较大,从而使得Inconel 600和Inconel 690合金氧化膜呈现出不同的微观结构。
A model of diffusion path analysis （DPA） was proposed to describe the microstructure and formation mechanism of oxide films on Inconel 600 and Inconel 690 in high-temperature and high-pressure water. First, a Ni-Cr- H20 ternary phase diagram was plotted according to the known composition of the alloys and oxide films, along with the environment factors. The diffusion path describing the oxidation of Inconel 600 in high-temperature and high- pressure water indicated that the surface films consisted of Cr2O3 inner layer and FeCr2O4 outer layer. According to the DPA for Inconel 690, the surface film was composed of Cr2O3 entirely. The diffusivity of O2- was higher than that of Cr3＋ in surface films on Inconel 600. The Cr2O3 film formed on Inconel 690 had a higher resistance to the transportation of oxygen through the film, and thus the mobility of oxygen was low. As a consequence, the surface films formed on Inconel 600 and Inconel 690 exhibited different microstructures.
出处
《腐蚀与防护》
CAS
北大核心
2016年第6期498-502,共5页
Corrosion & Protection
基金
国家核电技术有限公司资助项目(2015SN010-006)
关键词
扩散路径分析模型
镍基合金
高温水氧化
diffusion path analysis （DPA） model
nickel-based alloy
oxidation in high temperature water
