电弧熔炼Cr-40Ti-20Nb三元合金的组织与压缩性能  

Microstructure and Compression Properties of Cr-40Ti-20Nb Ternary Alloy Prepared by Arc Melting

作　　者：董旭坤[1] 李双明[1] 李克伟[1] 薛云龙[1] 傅恒志[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《铸造》2012年第6期592-594,597,共4页Foundry

基　　金：国家自然科学基金(50971101;51074127);高等学校博士学科点专项科研基金项目(20096102110011);西工大基础研究基金项目资助(JC201029)

摘　　要：采用真空非自耗电弧熔炼的方法制备了Cr-40Ti-20Nb（原子分数）合金。利用光学显微镜（OM）,X射线衍射（XRD）,扫描电镜（SEM）分析了合金不同凝固位置处的相组成和组织形态。结果表明,合金的凝固组织主要是由Laves相Cr（2Nb,T）i枝晶组织及Ti的固溶体组成。同时对合金的显微硬度和压缩性能进行了测试,显微硬度值在6 112~7 350 MPa之间,比Laves相Cr2Nb的显微硬度低20%。另外室温压缩屈服强度可达1 334~1 524 MPa,与采用多种合金化元素的Cr-12Nb-4Re-2Al合金相当,这表明Ti元素的添加不仅可以改变Laves相Cr2Nb合金的凝固组织,而且对其塑性也有很大程度的改善。The ternary alloy Cr-40Ti-20Nb was successfully prepared by vacuum non-consumable arc melting.The alloy solidified microstructure and compression behavior were investigated by using optical microscope（OM）,X-ray diffraction（XRD）as well as scanning electron microscope（SEM）.The results show that the solidified microstructure of the ternary alloy Cr-40Ti-20Nb was mainly composed of Laves phase Cr2（Nb,Ti）and Ti solid solution.As the solidification position was varied from the top to the bottom of the arc-melting ingot,the microhardness of the ternary alloy was measured ranging from 6 112 to 7 350 MPa,less than that of the Laves phase Cr2Nb by a factor of 20%.Moreover,the compression yield strengths of the ternary changed from 1 334 to 1 524 MPa at room temperature,close to that of the multi-component alloy Cr-12Nb-4Re-2Al.According to these experimental results,Ti additions not only change the solidified microstructures of the Laves-phase Cr2Nb alloy,but also remarkably improve the plasticity of the Laves phase Cr2Nb alloy.

关 键 词：真空非自耗电弧熔炼 Cr-Nb-Ti三元合金 微观组织 压缩性能 

分 类 号：TG132.32[一般工业技术—材料科学与工程]