机构地区: 洛阳工业高等专科学校材料工程系
出 处: 《腐蚀科学与防护技术》 2005年第4期227-229,共3页
摘 要: 通过循环氧化试验和SEM观察,研究了内氧化对扩散型热浸渗铝钢循环氧化性能的影响.结果表明,经高温扩散处理后,热浸镀铝钢扩散层的次外层和过渡层之间均有空洞产生.随扩散温度升高和时间延长,次外层和过渡层之间空洞逐步聚集连接成平行于表面的波浪线状空洞带,使高温氧化过程中扩散层产生了内氧化,氧化动力学曲线偏离平方抛物线规律而呈现抛物线—直线规律.因此,渗铝钢的长期氧化速度同时受扩散层内氧化和外氧化的控制.探讨了扩散层空洞带和内氧化的形成机理. The effect of internal oxidation in the diffusion layer on cyclic oxidation resistance of aluminizing steel was investigated.The results showed that,after high temperature diffusion treatment,the diffusion layer of aluminizing steel formed voids between the middle layer and the transitional layer,and the voids aggregated progressively into a wavy voids zone parallel to the surface with the temperature rising and time prolonging.This leaded to the internal oxidation of the diffusion layer during high temperature oxidation,and the kinetics curves of oxidation deviated the square parabola into the parabola—straight.Therefore,the long-term oxidation rate of aluminizing steel was controlled both by the external and internal oxidation of the diffusion layer.The formation mechanism of the voids and internal oxidation were discussed.