定向凝固NiAl-Mo过共晶合金组织演变及性能（英文）  

Microstructure Evolution and Mechanical Properties of a Directionally Solidified NiAl-Mo Hyper-Eutectic Alloy

作　　者：张建飞[1] 徐鹏飞[1] 董悦雷 郝文纬 张宇昊 Zhang Jianfei;Xu Pengfei;Dong Yuelei;Hao Wenwei;Zhang Yuhao(Inner Mongolia University of Science and Technology,Baotou 014010,China)

机构地区：[1]内蒙古科技大学

出　　处：《稀有金属材料与工程》2019年第11期3514-3518,共5页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51564041);the Natural Science Foundation of Inner Mongolia of China(2018MS05028);the Inner Mongolia University of Science and Technology Industry-Study-Research Found(PY201509)

摘　　要：采用液态金属高温度梯度定向凝固装置制备了NiAl-16Mo(原子分数,%)过共晶合金,研究了生长速率对合金组织演变及性能的影响。结果表明:在生长速率为12~300μm/s范围内,该合金的凝固组织为初生Mo枝晶与NiAl/Mo纤维共晶的混合组织。随生长速率的增加,初生Mo枝晶的体积分数由12μm/s的7.21%增加到300μm/s的11.42%,Mo枝晶尺度和间距同时随之减小。力学性能测试结果表明,室温断裂韧性和高温强度随生长速率增加而降低,同时对合金强韧化机理进行了探讨。A hyper-eutectic alloy,with nominal composition Ni-42 Al-16 Mo(at%),was directionally solidified at growth rates ranging in 12~300μm/s by liquid metal cooling(LMC)technique.Microstructural examination reveals that the NiAl-16 Mo alloy is composed of primary Mo dendrite and NiAl/Mo eutectic cell in all the growth conditions employed.With the growth rates increasing from 12 to 300μm/s,the volume fraction of Mo primary dendrite increases from 7.21%to 11.42%,while the size and the arm spacing of Mo primary dendrite reduces simultaneously.The corresponding room temperature fracture toughness(RTFT)and ultimate high temperature compressive strength(UTCS)decrease with the increase of growth rates.The toughening and strengthening mechanism of composite was also discussed.

关 键 词：晶体生长 金属间化合物 断裂韧性 压缩强度 

分 类 号：TG1[金属学及工艺—金属学]