复合材料粘弹性本构关系与热应力松弛规律研究_理论分析_刘书田.pdfVIP

22 　 1 　　2 　2005 Acta Mater iae Comp ositae Sin ica Vol.22　No.1 February　2005 :1000-3851 (2005)01-0152-06 Ⅰ: ＊ 刘书田 , 马　宁 ( , 116024) 　:　, 。 　　 , , 、 。 , :(1) , , , ;(2), , ;(3) , , 。 :　;;;; :　T 332;O343　　:A STUDY ON THE THERMAL STRESS RELAXATION AND CONSTITUTIVE EQUATIONS OF VISCOELASTIC COMPOSITE MATERIALS, PART I:GENERAL THEORY ＊ LIU Shutian , MA Ning (State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian 116024, China) Abstract:　 ased on the homogenization theory, the multi-scale analysis methods of the viscoelastic property, and the effective thermal stress relaxation laws are studied. y defining the concepts, the effective thermal stress relaxation modu- lus (ETSRM)and the effective time-dependent coefficients of thermal expansion (ETCTE), the thermalviscoelastic con- stitutive equationis expressed in the same form as that of conventionalmaterials. esides, a homogenization-based method for predicting the effective viscoelastic relaxation modulus, ETSRM and ETCET is given.It is pointed out that, for vis- coelastic composite materials, the thermal expansion coefficients are time-dependent, and the thermal expansion process can not be completed instantaneously, exhibiting an obvious time-delay effect.The analysis of several kinds of special composite materials show s that:(1)The thermal expansion of porousmaterial has aninstantaneous character, its ETCTE