【摘要】 研究了不同稀土含量铁铬铝合金,在高温下晶粒长大及界面结构。结果表明:在1200℃以上高温,稀土组元（以La为主）对抑制合金的晶界长大有一定效果,La₂O₃可作为TiN相析出的形核中心,细小TiN质点可在晶界上出现,阻碍晶界迁移;在变温过程中,La向界而扩散,在晶界以La₂O₃形式出现,同时稀土加速氧穿过氧化膜向基体中渗透,导致Al₂O₃及La₂O₃在基体中形成。更多还原

【Abstract】 The experiments have been performed to investigate the grain growth, the characterization of grain boundary migration and the interfacial phenomena at high temperature for Fe-25Cr-5Al-RE alloy. The results show that the rare earth (landium is main) has a certain effect on the grain growth of alloy; La2O3 may be the nuclear center of titanium nitride phases that precipitate in the matrix of the alloy; for Fe-Cr-Al-RE (RE<0.1%) fine titanium nitride may precipitate on the grain boundaries and inhibite the migration of grain boundaries; by repeated heating and cooling, the rare earth increases the permeation of O2- ions through the oxide scale, lanthanum atoms diffuse towards the interfaces and precipitate as lanthana. There is no doubt that the precipitates lanthana and alumina in matrix as a trapping of vacancies greatly increase the oxidation resistance and the life of the electric heating a lloy.更多还原