【摘要】 <正> 1.引言 材料在冶炼、加工和使用过程中,不可避免地存在各种初始缺陷或裂纹,对某些关键的或不易检修的构件（如螺旋桨叶、发动机气门弹簧等）,常采用无限寿命设计,期望其中的初始缺陷或裂纹不继续扩展。这要求应力强度因子变程△K小于疲劳裂纹扩展门槛值△K_th,而应力强度因子变程△K是应力变程△σ的函数X（△σ）与初始裂纹尺寸α₀的函数更多还原

【Abstract】 A model of ΔK-ΔKth interference is presented, which is applicable to the reliability analysis and design of infinite life for structural members with cracks. By means of the model the reliability of no crack growth may be obtained, and the maximum permissible crack size or load can be determined at a given reliability level.更多还原