Crack Growth Behavior of Tensile Overload for Small Load Amplitude at High-Low Block Stress Ratio

고-저블럭 응력비에서 하중진폭이 작은 인장과대 하중의 균열성장 거동

This paper examines the crack growth behavior of 7075-T651 aluminum alloy under high-low block loading condition. The cantilever beam type specimen with a chevron notch is used in this study. The crack growth and closure are investgated by compliance method. The applied initial stress ratios are R=-0.5, R=0.0 and R=0.25 Crack length($\alpha$), effective stress intensity factor range(ΔKeff), ratio of effective stress intensity factor range(U) and crack growth rate(d$\alpha$/dN) etc. are inspected fracture mechanics estimate.