本文分析了粉末烧结材料塑性变形的基本规律 ,指出了现有粉末烧结材料屈服条件与实际情况不相符的问题。通过烧结铜圆柱体试样单向压缩实验 ,确定了粉末烧结材料真实应力应变关系 ,建立了普适的粉末烧结材料屈服条件和塑性本构关系。本文的屈服条件不仅用统一的函数形式表示了粉末烧结材料初始屈服和后继屈服 ,而且综合反映了粉末烧结材料原始状况和变形致密强化对屈服的影响 In this paper, the basic rules of plastic deformation of powder sintered materials are analyzed, and the problems that the yield conditions of the existing powder sintered materials do not accord with the actual situation are pointed out. The uniaxial compression experiments of sintered copper cylinder specimens were carried out to determine the true stress-strain relationship of powder sintered materials and establish the yield conditions and plastic constitutive relations of the powder sintered materials. The yield conditions in this paper not only represent the initial yielding and subsequent yielding of the sintered powder material in a unified function, but also reflect the influence of the initial state of the powdery sintering material and the densification and compacting on the yielding