Ti2AlC triggered in-situ ultrafine TiC/Inconel 718 composites:Microstructure and enhanced properties  

作　　者：Wenqiang Hu Zhenying Huang Qun Yu Yuanbo Wang Yidan Jiao Cong Lei Leping Cai Hongxiang Zhai Yang Zhou 

机构地区：[1]Institute of Materials Science and Engineering,School of Mechanical and Electronic Control Engineering,Beijing Jiaotong University,Beijing,100044,China [2]Key Laboratory of Vehicle Advanced Manufacturing,Measuring and Control Technology(Beijing Jiaotong University),Ministry of Education,Beijing,100044,China

出　　处：《Journal of Materials Science & Technology》2020年第16期70-78,共9页材料科学技术（英文版）

基　　金：supported financially by the National Natural Science Foundation of China(Nos.51871011,51572017 and 51301013);the Beijing Government Funds for the Constructive Project of Central Universities;the Fundamental Research Funds for the Central Universities(No.2018YJS144)。

摘　　要：In situ ultrafine TiC dispersion reinforced Inconel 718 alloy with enhanced mechanical properties was fabricated by the technique of reactive hot-press sintering Ti2AlC and In718 powders.The effect of Ti2AlC precursor additions(5 vol.%,10 vol.%,15 vol.%)on microstructure and mechanical properties of TiC/In718 composites were investigated.A relationship of microstructural characteristics,room and elevated temperature mechanical performance,and underlying strengthening mechanisms were analyzed.The results show that initial Ti2AlC precursor transformed completely into ultrafine TiC particulate(~230 nm)and distributed uniformly in the matrix after sintering 5 and 10 vol.%Ti2AlC/In718.However,TiC particulates tended to aggregate to stripes with the addition of Ti2AlC up to 15 vol.%,which,in adverse,weaken the properties of In718.The 5 vol.%Ti2AlC/In718 sample showed a higher tensile strength of 1404±13 MPa with a noticeable elongation of 9.8%at room temperature compared to the pure In718(ultimate tensile strength(UTS)=1310 MPa,elongation=21.5%).At 600℃,700℃,800℃and 900℃,tensile strength of the as-sintered 5 vol.%Ti2AlC/In718 composite was determined to be 1333±13 MPa,1010±10 MPa,685±25 MPa and 276±3 MPa,increased by 9.2%,14.6%,14.2%and 55%,respectively,compared with that of monolithic In718 alloy.The excellent tensile properties of TiC/In718 composite can be ascribed to the combined mechanisms in term of increased dislocation density,dispersive Orowan and load transfer mechanisms.

关 键 词：Inconel 718 TiC reinforcement TI2ALC High temperature properties Tensile strength 

分 类 号：TB33[一般工业技术—材料科学与工程]