对Fe40Al60粉末压坯进行激光点燃自蔓延烧结,利用XRD、金相、硬度等表征手段,分析烧结合金表层区、中部区和底部区的微观组织结构及宏观性能,并采用有限元分析方法,对Fe40Al60激光烧结过程的温度场进行数值模拟,得到了烧结过程温度场分布云图和路径图。结果表明:表层区产物相主要为FeAl、Al2O3,中部区产物相为Fe3Al、FeAl、Al2O3,底层区产物相为Fe3Al、Al2O3和Fe;烧结合金表层区组织为条状,中部区组织为胞状,底层区组织为针状;表层区硬度HV为9010 MPa,中间层硬度HV为10 050 MPa,底层区硬度HV为9650 MPa。模拟结果表明:10 s时,表层区温度最高为1150 K,中部区温度为894.033 K,底层区温度最低为820.979 K。表明试样各区域物相与该区温度场模拟结果相一致。
Fe40Al60 alloy was prepared by laser ignition induced self-propagating high-temperature synthesis. The microstructure and macroscopic properties of different areas in the sintered alloy were investigated by XRD, microscopic tests and hardness tests. The temperature field of Fe40Al60 was simulated by finite element analysis software ANSYS. Contour maps of temperature field and the path map were obtained after sintering for 10 s. The results show that the main phases of the alloy surface are Fe Al and Al2O3, in the median layer are Fe3Al, FeAl and Al2O3, while in the bottom layer are Fe3Al, Al2O3 and Fe. The microstructure of the surface is strip-like, the median cellular, and the bottom fine needle. The hardness of 10050 MPa occurs in the median layer which is the highest, while that is 9010 MPa in the surface layer, and 9650 MPa in the bottom layer. The simulation result shows that at 10 s, the temperature of the direct laser sintering surface is up to 1150 K, the median is 894.033 K and the bottom 820.979 K, which are consistent with the XRD results.