基于三维数字图像相关法研究表面粗糙度和缺口对TC4钛合金拉伸性能的影响  

Effect of Surface Roughness and Notch on Tensile Properties of TC4 Titanium Alloy Based on Three Dimensional Digital Image Correlation Method

作　　者：段海涛 陈志新[1] 张哲 孙景涛 刘雨超 DUAN Haitao;CHEN Zhixin;ZHANG Zhe;SUN Jingtao;LIU Yuchao(School of Mechanical and Electrical Engineering,East China University of Technology,Nanchang 330013,China)

机构地区：[1]东华理工大学机械与电子工程学院,南昌330013

出　　处：《机械工程材料》2025年第4期34-39,共6页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(52365054)。

摘　　要：基于三维数字图像相关法,研究了表面粗糙度(0.745,1.055,1.395μm)和缺口半径(0,0.6,1.2 mm)对TC4钛合金室温拉伸性能以及紧缩阶段的位移场和应变场的影响。结果表明:随着表面粗糙度增加,无缺口试样的断后伸长率先减小后增大,抗拉强度增大,缺口试样的断后伸长率小幅增大,抗拉强度增大;随着缺口半径增加,断后伸长率先大幅减小后小幅回增,抗拉强度增大;同时增加表面粗糙度和缺口半径,断后伸长率减小,产生了逆向交互作用,抗拉强度显著增大,产生了正向交互作用;无缺口试样x方向变形不均、y方向(轴向)均匀延伸,x方向应变向中部、y方向应变向颈缩区集中;1.2 mm缺口半径试样位移场等高线呈弯曲状,密集分布于缺口处,应变场呈同心圆状,0.6 mm缺口半径试样位移场等高线呈斜线状向缺口处聚拢,但相比大缺口试样分布疏散,应变场呈不规则状。The effect of surface roughness(0.745,1.055,1.395μm)and notch radius(0,0.6,1.2 mm)on the tensile properties of TC4 titanium alloy at room temperature and the displacement field and strain field in the compaction stage was studied based on three dimensional digital image correlation method.The results show that with the increase of surface roughness,the percentage elongation after fracture of the unnotched sample first decreased and then increased,and the tensile strength increased;the percentage elongation after fracture of the notched sample increased slightly,and the tensile strength increased.With the increase of notch radius,the percentage elongation after fracture decreased significantly and then increased slightly,and the tensile strength increased.With the increase of surface roughness and notch radius,the percentage elongation after fracture reduced,showed a reverse interaction;the tensile strength increased,showed a positive interaction.As for unnotched sample,the deformation in x direction was uneven,the axial elongation in y direction was uniform,and the strain in x direction was high in the middle,and in y direction was concentrated in the necking zone.The contours of the displacement field of notched sample with 1.2 mm notch radius were curved and densely distributed at the gap,and the strain field showed concentric circles.The contours of the displacement field of notched sample with 0.6 mm notch radius were converged diagonally toward the gap,but the distribution was relatively open comparing with that of large-notched sample,and the strain field was irregularly distributed.

关 键 词：TC4钛合金 三维数字图像相关法 表面粗糙度 缺口 

分 类 号：TB31[一般工业技术—材料科学与工程]