CNTs添加对原位自生Ti2AlC增强高Nb-TiAl合金组织与力学性能的影响  

Effect of CNTs addition on microstructure and mechanical properties of high Nb-TiAl alloy reinforced by in-situ Ti2AlC

作　　者：金玉亮 朱冬冬[2] 王刚[1] 王晓红 马腾飞 董多[2] JIN Yu-liang;ZHU Dong-dong;WANG Gang;WANG Xiao-hong;MA Teng-fei;DONG Duo(School of Material Science and Engineering,Anhui Polytechnic University,Wuhu 241000,China;Key Laboratory of Air-driven Equipment Technology of Zhejiang Province,Quzhou University,Quzhou 324000,China)

机构地区：[1]安徽工程大学材料科学与工程学院,安徽芜湖241000 [2]衢州学院浙江省空气动力装备技术重点实验室,浙江衢州324000

出　　处：《材料热处理学报》2022年第11期19-26,共8页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52071188,52171120)。

摘　　要：以碳纳米管(CNTs)、高纯Al、高纯Ti与高纯Nb颗粒为原料,采用真空电弧熔炼的方法制备了原位自生Ti2AlC增强Ti-45Al-8Nb合金,研究不同CNTs添加量对Ti-45Al-8Nb合金组织与力学性能的影响。结果表明:合金的组织主要由(α_(2)-Ti_(3)Al+γ-TiAl)片层、γ-TiAl相、B2相、Ti2AlC相及微量TiC相构成,Ti2AlC增强相呈棒状存在于片层团内部和晶界处,随着CNTs添加量增加,Ti2AlC相体积分数增多同时长径比减小。合金的硬度随CNTs添加量增加而增加,当CNTs添加量为0.9 mass%时,合金硬度达到658 HV。当CNTs添加量为0.6 mass%时,合金室温抗压强度与压缩率最佳,分别为1784 MPa与21.8%,相较未添加CNTs的Ti-45Al-8Nb合金,抗压强度提高了约48.7%,压缩率提升了约59.1%。CNTs的添加显著提升了合金在800℃下的抗压强度,CNTs添加量为0.6 mass%时,抗压强度由900 MPa提升至1190 MPa,提升了约32.2%。合金力学性能的提高主要是由于细晶强化、固溶强化和Ti_(2)AlC相增韧的共同作用所致。Using carbon nanotubes(CNTs),high-purity Al,high-purity Ti and high-purity Nb particles as raw materials,Ti-45 Al-8 Nb alloy reinforced by in-situ TiAlC was prepared by vacuum arc melting.The effect of different CNTs additions on microstructure and mechanical properties of the Ti-45 Al-8 Nb alloy was studied.The results show that the microstructure of the alloy is mainly composed of(α_(2)-Ti_(3)Al+γ-TiAl)lamella,γ-TiAl phase,B2 phase,TiAlC phase and trace TiC phase.The TiAlC reinforcing phase exists in the interior of the lamella and at the grain boundary as a rod shape,and with the increase of CNTs addition,the volume fraction of the TiAlC phase increases and the aspect ratio decreases.The hardness of the alloy increases with the increase of CNTs addition.When the addition of CNTs is 0.9 mass%,the hardness of the alloy reaches the max value of 658 HV.When the addition of CNTs is 0.6 mass%,the compressive strength and compression ratio of the alloy at room temperature are the best,which are 1784 MPa and 21.8%,respectively.Compared with the Ti-45 Al-8 Nb alloy without CNTs,the compressive strength is increased by about 48.7%and the compression ratio is increased by about 59.1%.The addition of CNTs significantly improves the compressive strength of the alloy at 800℃.When the addition of CNTs is 0.6 mass%,the compressive strength increases from 900 MPa to 1190 MPa,an increase of about 32.2%.The improvement of mechanical properties of the alloy is mainly due to the combined effect of fine grain strengthening,solid solution strengthening and Ti_(2)AlC phase toughening.

关 键 词：TIAL合金 CNTS 显微组织 力学性能 

分 类 号：TB333[一般工业技术—材料科学与工程]