给定寿命下的焊趾疲劳裂纹深度尺寸分析

Distribution of Depth Size of Fatigue Crack at Weld Toes for a Given Life

本文提供并用统计方法研究了焊趾疲劳裂纹扩展的Ｎ～α曲线族，给出了联系给定裂纹尺寸下的疲劳寿命分布，给定疲劳寿命下的裂纹尺寸分布以及随机初始条件的概率相容条件。研究表明，给定寿命下的焊趾疲劳裂纹深度尺寸α服从分布Φ［（μ（α）－ｌｏｇＮ）／σ（α）］。

This paper provides and studies statistically the N versus a curve family which describes the fa-tigue crack growth at weld toes. A probability compatible condition is given, which relates the distri-bution of fatigue life for a given crack size to the distribution of crack size for a given fatigue life andthe random initial condition of the fatigue crack propagation. Furthermore, it is confirmed that thedepth size a of fatigue cracks at weld toes follows the distribution Φ( (μ(a)-LogN)/σ(a))for a givenlife.