基于非线性连续损伤的机床轴结构疲劳研究

运用MINER线性累积损伤理论对机床轴结构进行疲劳研究时,由于不能连续描述损伤与载荷之间的关系,在高周疲劳寿命预测过程中其计算结果不能令人满意。为此,基于CHABOCHE提出的单轴非线性连续累积损伤理论,通过对45钢进行疲劳试验获得了轴结构材料的S-N曲线,在对机床载荷谱简化处理的基础上,建立了适于机床轴结构寿命预测的多轴非线性连续损伤累积模型。实例计算证明,该模型能准确描述机床轴结构损伤累积过程,计算结果更符合工程实际。

Study on Shaft Structural Fatigue of Machine Tool Based on Non-linear Continuum Damage Model

When the linear damage accumulation theory was used for study on shaft structural fatigue of machine tool, since the relationship between damage and load was unable to be described continuously, the calculation result in high cycle fatigue life prediction is not satisfactory. Therefore, based on the no-linear continuum damage accumulation theory presented by CHABOCHE, a multi axial non-linear continuum damage accumulation model suitable for shaft structural fatigue life prediction of machine tool was established, according to the shaft structural material S-N curve obtained from steel No. 45 fatigue test and based on the simplification of cyclic load spectrum of machine tool. The calculation in particle example proves that the model can accurately describe the damage accumulation process of shaft structure of machine tool, and gives a result meeting practice projects.