【摘要】 本文用十字型试件研究了侧向静载荷下斜裂纹的疲劳扩展，实验表明裂纹拐弯扩展后，沿着使Ⅰ型应力强度因子幅趋于零的路径扩展，裂纹以穿晶方式向前扩展，受Ⅱ型应力强度因子的影响裂纹扩展速率经历了由大→小→大的过程，侧向静载荷下斜裂纹的扩展速率较Ⅰ型扩展速率要大，侧向负载荷能促使扩展速率增加，侧向正静载荷使扩展速率降低。更多还原

【Abstract】 In this paper, fatigue crack propagation tests were carried out in cruciform specimens in which a center initial crack orient at 45 deg. The crack was deflected. In all the cases the deflected crack propagated in the mode Ⅰ, namely △K_Ⅱ I was almost always zero along the crack paths. Crack propagation with transgranular was observed. Crack growth rate was large at begin then decreased. After propagated about 2mm, crack growth rate was increased again. The inclining crack growth rate was larger than the growth rates of mode Ⅰ crack, when one loading was static and the other was cyclic loading. The compressive static loading act to increase the growth rate, while tensile loading decrease it.更多还原