摘要
用LY12CZ和 3 0CrMnSiNi2A两种材料制成中间有类椭圆孔的试件 ,对战斗机随机谱载下的寿命试验结果 ,分别用局部应力应变法和裂纹扩展的方法对裂纹形成寿命进行计算 ,并讨论上述两种方法的优缺点。用相对Miner法则修正的局部应力应变法能较好地估算随机谱载下的寿命 ,也指出损伤的线性累积不是很合理 ,大过载及载荷顺序等参数在局部应力应变法中对寿命的影响不是直接的 ,在裂纹扩展的方法中能较好解决这些问题。一般用裂纹扩展方法计算的寿命比局部应力应变法更符合试验的结果。
The local stress strain method and the crack growth method are used to compute the crack initiation life under fighter random spectra. The specimens with similar ellipse hole in the center are made from LY12CZ, 30CrMnSiNi2A materials. The advantages and disadvantages of the two methods are discussed. The life under random spectra can be well estimated by the local strain stress method with relative Miner correction. Linear cumulative damage is unreasonable, the influence of heavy overload and load order upon life can not be directly taken into account when the local stress strain method is used. Such problems can be resolved when the crack growth method is used. In general, the results computed by the crack growth method are in better agreement with the experimental results than the ones by the local stress strain method.
出处
《机械强度》
CAS
CSCD
北大核心
2003年第3期267-270,共4页
Journal of Mechanical Strength
