【摘要】 介绍了最小耗能原理及其建立材料强度准则的一般步骤,在强度准则通常为能量蓄积程度表达式这一前提下,从最小耗能原理出发,利用线粘弹性断裂理论推导了裂纹蠕变的稳定性准则。为对比起见,将线弹性断裂理论的应变能密度因子断裂判据直接推广到粘弹性状态,得到了与最小耗能原理相同的稳定性准则表达式,并分析了几种流变材料中裂纹蠕变的长期稳定性。更多还原

【Abstract】 The principle of minimum energy dissipation and its general procedures to establish strength criterion of materials, have been introduced. With the widely accepted viewpoints that strength criteria express the energy accumulation of material and utilizing the viscoelastic fracture theory the strength criteria for crack creep are deduced. For the sake of contrast these viscoelastic equations are also obtained directly from strength criterion of elastic fracture theory in form of strain energy density. Therefore creep stability of fracture in several kinds of viscoelastic material is analyzed.更多还原