机构地区: 西安理工大学材料科学与工程学院
出 处: 《材料热处理学报》 2005年第4期106-110,共5页
摘 要: 通过高温氧化试验和扫描电镜观察,研究渗铝钢在800℃氧化后次外层过渡层界面空洞的形态、分布和生成过程,测定空洞平均直径和深度随氧化时间的变化。结果表明,空洞侧面常含有特殊的结晶学小平面,其可能达到的平衡形状在某种程度上依赖于合金晶粒的晶体几何;随氧化时间增加,空洞形态逐渐由圆币型向多边型演变,其分布由沿三维圆锥面立体分布转变为二维平面分布;空洞的生长可以划分为快速生长和稳定生长两阶段;空洞带深度随时间先快速增加而后保持不变。探讨了界面空洞的形成机制和空洞带的形成过程。 The shape, distribution and formation of voids along the interface between the subsurface layer and transition layer of aluminized steel during oxidation at 800°C were investigated. The variations of the average size and depth of the interfacial voids with oxidation time were examined by means of scanning electron microscopy (SEM). The results show that the wall of voids usually has particular crystallographic facets and the equilibrium shape of the voids has some dependence of the crystal orientation of the surrounding matrix. With oxidation time prolonging, the spherical voids become gradually polygonal void and its distribution changes from three-dimensional conical type into two-dimensional plane type. The growth of the voids can be divided into two stages: fast growth and stable growth. The depth of voids band first increases quickly and then unchanged. The formation mechanisms of the voids are discussed.