硅化物涂层对Nb‒Ti‒Al合金力学性能的影响  

Effect of silicide coating on mechanical properties of Nb‒Ti‒Al alloys

作　　者：赵刚[1,2] 周小军 梁斌 白晓东 蔡圳阳 杨生春[1] ZHAO Gang;ZHOU Xiao-jun;LIANG Bin;BAI Xiao-dong;CAI Zhen-yang;YANG Sheng-chun(Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter,Xi’an Jiaotong University,Xi’an 710049,China;Ningxia Orient Tantalum Industry Co.,Ltd.,Shizuishan 753000,China;National Tantalum and Niobium Special Metal Materials Engineering and Technology Center,Shizuishan 753000,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]西安交通大学教育部物质非平衡合成与调控重点实验室,西安710049 [2]宁夏东方钽业股份有限公司,石嘴山753000 [3]国家钽铌特种金属材料工程技术中心,石嘴山753000 [4]中南大学材料科学与工程学院,长沙410083

出　　处：《粉末冶金技术》2022年第6期494-498,共5页Powder Metallurgy Technology

基　　金：国家自然科学基金资助项目(51901252);宁夏回族自治区自然科学基金资助项目(2019AAC03284);湖南省自然科学基金资助项目(2020JJ5713,2020JJ5737)。

摘　　要：采用真空电弧炉熔炼法制备低密度Nb‒Ti‒Al合金铸锭,利用料浆烧结法在铸锭表面涂覆Si‒Cr‒Ti复合硅化物涂层,使用万能电子拉伸试验机对合金试样和涂层试样进行力学性能测试,研究硅化物涂层对试样力学性能的影响。结果表明,与合金试样相比,涂覆涂层后的低密度铌合金室温力学性能(抗拉强度、屈服强度及延伸率)显著下降。为进一步研究涂覆涂层合金力学性能下降的原因,采用扫描电子显微镜和能谱仪对合金试样和涂层试样进行显微组织观察、涂层/基体界面成分分析及C含量(质量分数)测定。结果表明,涂层试样力学性能下降的主要原因包括涂覆涂层后合金晶粒显著长大,合金中强化元素Al的向外扩散,脆性相Nb3Al的形成以及Si‒Cr‒Ti涂层对合金产生的“渗沉效应”。he low-density Nb‒Ti‒Al alloy ingots were prepared by vacuum arc furnace smelting method in this paper,the Si‒Cr‒Ti composite silicide coatings were deposited on the surface of Nb‒Ti‒Al alloys by the slurry sintering method,and the universal electronic tensile testing machine was used to study the effect of silicide coating on the mechanical properties of the uncoated and coated alloys.The results show that,the mechanical properties(tensile strength,yield strength,and elongation)at room temperature of the coated low-density niobium alloys are significantly reduced,comparing with the uncoated alloys.To investigate the reasons for the decrease in the mechanical properties of the uncoated alloys,the scanning electron microscope(SEM)and energy dispersive spectrometer(EDS)were used to observe the microstructure,analyze the composition of interface between coating and substrate,and test the C content(mass fraction)of the uncoated and coated alloys.In the results,the main reasons for the decrease in the mechanical properties of the coated niobium alloys are the significant growth of the alloy grains,the outward diffusion of the strengthening element Al,the formation of the brittle phase Nb3Al,and the“seepage effect”of the alloy due to the Si‒Cr‒Ti coating.

关 键 词：硅化物涂层 Nb−Ti−Al合金 低密度铌合金 力学性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]