双剪统一强度理论计算塑性金属材料强度的唯一性

来源期刊：中南大学学报(自然科学版)2008年第6期

论文作者：刘光连

文章页码：1280 - 1284

关键词：双剪统一强度理论；屈服；塑性；金属

Key words：twin-shear unified strength theory; yield; plastic; metal

摘    要：研究了双剪统一强度理论及其有关关系式，得到塑性金属材料双剪统一强度理论参数b的计算式，对某一塑性金属材料，其值为常数，取值范围是b＞-1；运用双剪统一强度理论计算某一塑性金属材料的强度时有唯一确定的强度计算值，而不是多个值，不能得出塑性金属材料的τ_s/σ_s；分析材料的拉压强度比为1时双剪统一强度理论的2组等价变换式，对b＜0的材料，双剪统一强度理论计算表明，材料的破坏不是由中间主剪应力引起，这与双剪统一强度理论的假设矛盾；该理论不适用于三向等值拉应力状态的计算。

Abstract: Twin-shear unified strength theory and its related functions were studied. The formula of parameter b in the twin-shear unified strength theory for a certain plastic metal was developed and its value was determined to be constant for a certain plastic metal and its value range is b＞-1; only a certain value can be obtained when the strength of a plastic metal based on the twin-shear unified strength theory was calculated and the value of t_s/s_s could not be obtained. The results show that based on the analysis of the two equivalent equations of the twin-shear unified strength theory when the ratio of tensile strength to compressive strength equals 1, for materials with b＜0, the fracture of materials is not caused by the intermediate principal shear stress, which does not agree with the hypothesis of the twin-shear unified strength theory, and this theory can not be applied in stress state such as equitriaxial tension.