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结合实验讨论了残余应力对裂纹扩展作用的模型及其存在的问题．指出用公式ΔＫ＿（ｅｆｆ）＝（Ｋ＿（ｍａｘ）＋λＫ＿ｒ）－Ｋ＿（ｏｐ）可较准确地计算出残余压应力场中裂纹的扩展速率．残余压应力既使裂纹闭合力提高，又使最大应力强度因子降低，两者均使裂纹扩展驱动力ΔＫ＿（ｅｆｆ）减少，因而降低了裂纹的扩展速率．
The model of the effect of residual stress on crack propagation and its existing problems are discussed with experiments. It is pointed out that the rate of crack propagation in the residual compressive stress field can be calculated more accurately by using the formula ΔK eff = (K max + λK_r) -K op. The residual compressive stress not only increases the crack closing force but also decreases the maximum stress intensity factor, both of which decrease the crack propagation driving force ΔK eff and thus reduce the crack propagation rate.