摘要
采用基于脉冲等离子弧的增材制造技术在Q235基板上加工了Inconel 718合金试样,通过改变功率和焊接速度研究了不同热输入对试样组织与性能演变规律的影响。借助光学显微镜、扫描电镜、能谱分析、维氏硬度仪等手段对试样晶粒形态、枝晶间距、元素偏析、析出相成分及分布、显微硬度等进行表征,结果表明随着热输入从1.08×106 J/m增大至1.76×106 J/m,晶粒形态从细长的柱状枝晶逐渐转变为粗大的胞状枝晶,枝晶间距从6.34μm增大至9.09μm,Nb、Mo等元素在枝晶间偏析加剧,Laves相由颗粒状、块状逐渐变为长链状,显微硬度不断下降。
The effect of heat input on microstructure and mechanical property of pulsed plasma arc additive manufactured Inconel 718 superalloy samples were investigated.Five different heat inputs ranging from 1.08×10^6 J/m to 1.76×10^6 J/m were adopted by changing power and welding speed.The microstructure morphology,dendritic spacing,elemental segregation and interdendritic Laves phase were also studied by using optical microscopy(OM),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The results show that as the heat inputs increase,the microstructure morphology is changed from columnar dendrites to cellular dendrites,and dendritic spacing also increases from 6.34μm to 9.09μm.Consequently,elemental segregation of Nb and Mo are promoted so that the morphology of interdendritic Laves phase is changed from particles to chains,which leads to the decrease of microhardness.
作者
王凯博
吕耀辉
刘玉欣
孙哲
徐滨士
WANG Kaibo LU Yaohui LIU Yuxin SUN Zhe XU Binshi(National Defense Key Laboratory for Remanufacturing Technology, Academy of Armored Force Engineering, Beijing 100072)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2017年第14期100-104,共5页
Materials Reports
基金
国家重点研发计划项目(2016YFB1100201)
关键词
热输入
增材制造
脉冲等离子弧
组织
heat input
additive manufacturing
pulsed plasma arc
microstructure