Dependence of mechanical properties on the microstructure characteristics of a near β titanium alloy Ti-7333  

作　　者：Ruifeng Dong Jinshan Li Hongchao Kou Jiangkun Fan Bin Tang 

机构地区：[1]State Key Laboratory of Solidification Processing, Northwestern Polytechnical University [2]National & Local Joint Engineering Research Center for Precision Thermoforming Technology of Advanced Metal Matfigerials

出　　处：《Journal of Materials Science & Technology》2019年第1期48-54,共7页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Grant No.51711530151);the Major State Research Development Program of China(Nos.2016YFB0701303 and 2016YFB0701305)

摘　　要：In this work, the microstructure and the corresponding tensile properties of the rolled Ti-7Mo-3Nb-3Cr-3Al(Ti-7333) alloy before and after the thermal treatments were investigated. The results show that a strong α-fiber texture is developed in the rolled Ti-7333 alloy. The deformed matrix and the texture significantly induce the variant selection of β phase. The high strength of the rolled Ti-7333 alloy is attributed to the <110> texture parallel to the tensile direction and the dispersed α phase within the matrix. After the solution treatment followed by the aging treatment, the texture decreases and the microstructure consists of the equiaxed β grains, the spheroidal α_p phase and various needle-like α variants. Eventually, the alloy could achieve an optimal combination with the strength of about 1450 MPa,the ductility of about 10.5% and a considerable shear strength of about 775 MPa. This balance can be ascribed to the performance of the spheroidal α_p phase and various needle-like α_s variants. The results indicate that the Ti-7333 alloy could be a promising candidate material for the high-strength fastener.In this work, the microstructure and the corresponding tensile properties of the rolled Ti-7Mo-3Nb-3Cr-3Al(Ti-7333) alloy before and after the thermal treatments were investigated. The results show that a strong α-fiber texture is developed in the rolled Ti-7333 alloy. The deformed matrix and the texture significantly induce the variant selection of β phase. The high strength of the rolled Ti-7333 alloy is attributed to the <110> texture parallel to the tensile direction and the dispersed α phase within the matrix. After the solution treatment followed by the aging treatment, the texture decreases and the microstructure consists of the equiaxed β grains, the spheroidal α_p phase and various needle-like α variants. Eventually, the alloy could achieve an optimal combination with the strength of about 1450 MPa,the ductility of about 10.5% and a considerable shear strength of about 775 MPa. This balance can be ascribed to the performance of the spheroidal α_p phase and various needle-like α_s variants. The results indicate that the Ti-7333 alloy could be a promising candidate material for the high-strength fastener.

关 键 词：Near β TITANIUM alloy HOT-ROLLED Ti-7333 TEXTURE Thermal treatment α phase Mechanical properties 

分 类 号：TG339[金属学及工艺—金属压力加工] TG156