为了深入研究罗德系数的物理意义及应用,利用理论分析方法,推导出罗德系数与应力场特征量J2不变量、应变增量关系的表达式,直观地给出罗德系数与二者间的定量变化规律。对罗德系数与塑性变形复杂程度、变形类型的关系进行表征,揭示应力状态与金属瞬时变形流动行为的内在联系。并以典型塑性工艺过程为例,通过罗德系数的数值分布确定了工件全场的应变类型,进而为金属塑性变形流动行为的定量分析提供理论依据,这对于分析金属塑性成形问题及其在实际中应用具有重要意义。
In order to study the physical meaning and application of Lode parameter in depth, expression of relation between Lode parameter and invariants of the deviator J2, strain increment is deduced by theoretical analysis. The inherent relation between stress state and metal flow behavior of transient deflection is revealed through analyzing the relationship between Lode parameter and complexity of the plastic deformation, type of deformation. With examples of typical plastic process, distribution of Lode parameter's value determines type of deformation, and this provides a theoretical basis for the quantitative analysis of metal flow behavior of plastic deformation. It has important significance to the analysis of metal plastic forming and its application.