摘要
利用激光增材制造技术制备了Ti6Al4V/Inconel718功能梯度材料,研究了该梯度材料的成分及相组成、显微组织和显微硬度的变化。研究表明:沿组成梯度方向发生了一系列相变:α+β→β+Ti2Ni+TiCr2+Ti-Fe→β+TiNi+TiCr2+Ti-Fe→γ+Laves,过渡层主要是由TiNi和Ti2Ni以及Ti-Cr和Ti-Fe等二元相组成的混合体;沿材料底部至顶部微观组织发生了由魏氏α片层组织转变为等轴β晶组织,再由等轴β晶组织外延生长为细小树枝晶组织;显微硬度结果表明:硬度的增加主要与α相体积分数的减少,β相及Ti-Ni、Ti-Cr和Ti-Fe析出相的增加,以及固溶硬化和晶粒细化作用有关,本研究中最大值为8230 MPa。
Ti6Al4V/Inconel718 functionally graded materials were fabricated by laser additive manufacturing technology.The composition,phase composition,microstructure and microhardness of the gradient materials were studied.The results show that a series of phase transitions occur along the composition gradient direction:α+β→β+Ti2Ni+TiCr2+Ti-Fe→β+TiNi+TiCr2+Ti-Fe→γ+Laves.The transition layer is mainly composed of binary phases including TiNi,Ti2Ni,Ti-Cr,Ti-Fe,etc;the microstructure from the bottom to the top of the material changes from the Widmanstättenα-laths structure to the equiaxedβstructure,and then it is epitaxially grown from equiaxedβstructure into fine dendritic structure.The results of microhardness test show that the increase of hardness is mainly related to the decrease ofαphase volume fraction,the increase ofβphase,Ti-Ni,Ti-Cr and Ti-Fe phase,solid solution hardening and grain refinement.The maximum value in this study is 8230 MPa.
作者
黄金鑫
孙中刚
常辉
唱丽丽
邢飞
周廉
Huang Jinxin;Sun Zhonggang;Chang Hui;Chang Lili;Xing Fei;Zhou Lian(Nanjing Tech University,Nanjing 210009,China;Nanjing Zhongke Raycham Laser Technology Co.Ltd,Nanjing 210038,China;Shangi Institute for Advanced Materials(Nanjing)Co.Ltd,Nanjing 210038,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2020年第8期2813-2819,共7页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51875274)。
