Study On Mechanical Behavior Of Flexible Composite Structure In The Thermal Curing Process

Flexible composite structure is a new type structure which can be fold and unfold, its main structure material is fiber reinforced composite. In the process of fiber reinforced composites curing, it's followed with curing contraction and fiber,resin material expand with heat and contract with cold, this will lead to emerge the curing residual stress of the composite material, residual stress of the material has a significant effect on mechanical and aging properties. In this paper, the unidirectional fiber reinforced composites cooling from the curing temperature during the preparation are studied.First of all, the paper established the residual stress test system and the finite element model analysis for the thermal residual stress of the unidirectional fiber reinforced composite, apply the experimental test and the finite element method analysis the curing residual stress of the unidirectional fiber reinforced composite, and compared the finite element result and the experimental results, the results show that the finite element analysis and the experimental results are consistent, prove that the finite element model which established in the paper is correct and reliable. At the same time, the compared results show that the resin curing contraction caused by residual stress is smaller, and can be ignored in some conditions.This paper studies the influence law of the thermal residual stress with changing the curing temperature, elastic modulus of the reinforced material, matrix material elastic modulus of the elastic modulus, fiber volume content of etc. the results show that, curing temperature has significant effects on the curing residual stress of the fiber reinforced composites, the curing temperature higher, the residual stress of composite material higher; The elastic modulus of the fiber and resin has the same influence on the composite: the elastic modulus higher the cure residual stress higher; the fiber volume content higher the the residual stress of the composite materials are higher; the residual stress of the carbon fiber composite are higher than the aramid fiber's.This paper analyzes the influence of the vibration characteristics about the residual stress of the rigidization inflatable tube in different curing temperature, the results show that the higher the temperature, the higher curing residual stress; the higher residual stress is, the higher vibration frequency of the rigidization inflatable tube is, and the zero residual stress tube has the lowest vibration frequence.