摘要
采用激光熔化沉积方法在Fe基材料中获得(Ti,Nb)C复合碳化物颗粒增强相,分析了(Ti,Nb)C颗粒增强Fe基材料的组织特征、界面形成机理以及激光热输入对碳化物析出量的影响规律。在此基础上,通过调节加工参数优化了(Ti,Nb)C颗粒增强Fe基材料的力学性能。结果表明:(Ti,Nb)C颗粒增强Fe基材料的物相主要由α-Fe基体以及(Ti,Nb)C复合碳化物增强颗粒组成,α-Fe晶粒和(Ti,Nb)C碳化物通过低指数晶面的结合获得了匹配良好的界面取向。随着激光热输入的增大,材料中(Ti,Nb)C颗粒尺寸和面积比明显增加,而(Ti,Nb)C颗粒增强Fe基材料的抗拉强度随热输入的增加呈先增后减小的趋势,当热输入105 J·mm^(-2),抗拉强度最大,为653 MPa。从拉伸应力–应变曲线与断口微观组织形貌可以看到,(Ti,Nb)C颗粒增强Fe基材料表现出良好的韧性,受外部加载时,(Ti,Nb)C复合碳化物颗粒可以吸收和分散应力,阻碍位错和裂纹的扩展,从而达到增强材料力学性能的效果。
The(Ti,Nb)C composite carbide particle-reinforced phases were obtained in the Fe-based materials by laser melting deposition method.The microstructure characteristics and interface formation mechanism of the(Ti,Nb)C particle-reinforced Fe-based materials were studied,and the influence of laser heat input on the carbide precipitation were analyzed.On this basis,the mechanical properties of the(Ti,Nb)C particle-reinforced Fe-based materials were optimized by adjusting the processing parameters.The results show that the phases of the Fe-based materials reinforced by(Ti,Nb)C particles are mainly composed of theα-Fe matrix and(Ti,Nb)C composite carbide reinforced particles.Theα-Fe grains and(Ti,Nb)C carbides show the well-matched interfacial orientation through the combination of low-index crystal planes.Meanwhile,with the increase of heat input,the size and the area ratio of(Ti,Nb)C particles in the materials increase significantly.The tensile strength of the(Ti,Nb)C particle-reinforced Fe-based materials shows a trend of increasing first and then decreasing with the increase of heat input.When the heat input is 105 J·mm^(-2),the tensile strength is the maximum,which is 653 MPa.It can be seen from the tensile stress-strain curves and microstructure of the fracture surface that the(Ti,Nb)C particle-reinforced Fe-based materials exhibit good toughness.The(Ti,Nb)C composite carbide particles subjected to external loading can absorb and disperse stress,hinder the propagation of dislocations and cracks,thereby achieving the effect of enhancing the mechanical properties of the materials.
作者
李庆棠
张宇辰
吴海荣
LI Qingtang;ZHANG Yuchen;WU Hairong(Beijing Xinfeng Areospace Equipment Co.,Ltd.,Beijing 100854,China;Queen Mary University of London Engineering School,Northwestern Polytechnical University,Xi’an 710129,China)
出处
《粉末冶金技术》
北大核心
2025年第3期359-366,共8页
Powder Metallurgy Technology
关键词
激光熔化沉积
颗粒增强
Fe基材料
微观组织
力学性能
laser melting deposition
particle reinforcement
Fe-based materials
microstructure characteristics
mechanical properties
作者简介
通信作者:吴海荣,E-mail:359958370@qq.com。
