不同热处理温度下LaFe11.6 Si1.4合金的相和组织结构

摘要

研究了经不同温度热处理后的 LaFe11.6 Si1.4合金的相和组织结构,并探究其相变机理.铸态 LaFe11.6 Si1.4合金在高温热处理时经历包析反应和包晶反应.在低于1423K 左右时,铸态 LaFe11.6 Si1.4合金发生 Fe(Si)+LaFeSi→1∶13固固包析反应；在1423~1593K,发生 Fe(Si)+LaFeSi→1∶13固液包晶反应；在1593~1739K,已形成的1∶13相熔化,合金处于固相 Fe和液相两相区.基于相变热力学及动力学的因素,铸态合金在1523 K 附近具有最大的包晶反应驱动力,LaFe11.6 Si1.4合金热处理5小时后,合金1∶13相含量最高.%A research is made of the phase and structure of LaFe11.6 Si1.4 alloys undergoing a heat treatment at different temperatures,and to explore the mechanism of the phase transition.The LaFe11.6 Si1.4 cast alloys undergoes the peritectoid re-actions and peritectic reaction under high temperature heat treatment.At the temperatures of less than about 1423K,the cast alloy undergoes LaFe11.6 Si1.4 Fe (Si)+ LaFeSi → 1∶13 Solid Solid peritectoid reaction;at the temperatures of 1423~1593K, it undergoes Fe (Si)+ LaFeSi → 1∶ 13 solid-liquid peritectic reaction;while in temperatures of 1593~1739K,1∶13 has formed a molten phase,Fe alloys are found in a solid/liquid two-phase state.Based on factors of phase transition thermody-namics and kinetic phase transition,cast alloy at 1523K possesses a maximum peritectic reaction driving force,after 5 hours of heat treatment of LaFe11.6 Si1.4 alloy,the 1∶13 alloy is of the highest phase content.