【摘要】 针对测量单边缺口拉伸(SENT)试样的裂纹尖端张口位移(CTOD)阻力曲线时，延性裂纹扩展量的计算过于复杂的问题，提出了一种由数字图像相关技术(DIC)计算的变形场来确定裂纹尖端位置，并快速推算延性裂纹扩展量的方法。该方法首先在缺口和裂纹上下方的弹性区域设置两条平行横线；然后通过两条横线间的位移差构建曲线，曲线变化幅度的临界点即为裂纹端部的位置；根据临界点位置计算裂纹扩展量，最后测量CTOD并构建阻力曲线。将本文方法与另一种通过DIC测量SENT试样CTOD阻力曲线的方法进行对比，结果表明本文方法经过简便的计算后拟合的阻力曲线效果更好。更多还原

【Abstract】 Aiming at the problem that the calculation of the ductile crack growth is too complicated when measuring the CTOD resistance curve of SENT specimens, a new method was proposed to determine the crack tip location and calculate the ductile crack growth rapidly by using the deformation field calculated by digital image correlation technology(DIC). Firstly, two parallel horizontal lines were set up in the elastic region above and below the notch and crack, and then a curve was constructed according to the displacement difference between the two horizontal lines. The critical point of the curve variation amplitude was the position of the crack end, and the crack growth was calculated according to the critical point position. Finally, the crack tip opening displacement(CTOD) was measured and the resistance curve was constructed. The proposed method was compared with another method to measure the resistance curve of CTOD SENT samples by DIC, and the results showed that the proposed method had better fitting effect after simple calculation.更多还原