树脂基复合材料内应力测试与分析

将多片双向应变花预埋在平行于环氧树脂基体界面的胶层的不同深度,通过电阻应变仪测定了胶层在室温下的固化应变和在一定的环境温差作用下的纵横向应变随时间的变化情况。结果表明,在固化完成之前,表层处所测得的横向应变值最低,随时间的推移逐步增加而在超过24 h后达最大值;紧邻树脂基体-金属界面处所测得的纵横应变值在固化完成后均为最低,即纵横向内应力均为最大值。将设置于表层的应变片S4测得的应变值视为自由应变值,大致估算了环氧树脂基体固化开始至180 h之间在不同深度的内应力。 

ANALYSIS ON THE INNER STRESS IN RESIN BASED COMPOSITE

The inner stress in an epoxy adhesive layer deposited on the steel plate at room temperature is studied.With embedded strain gauges in arranged depth of the epoxy layer,the strain changes in the adhesive layer induced by the curing procedure and the changes of environment temperature were measured to evaluate the changes of the inner stress in places during one week.The results from experiment show that the lowest transversal strain is recorded at the layer near the surface,but the highest value is recorded after 24 h.At the point near the interface the stresses are the highest when the curing procedure is about accomplished.The inner stresses in the epoxy adhesive layer during curing to 180 h were estimated based on the strain obtained from the surface of the adhesive layer.