Quantitative Evaluation and Analysis of Interface Sliding Shear Stress using Stress Transfer at Real Contact Area of Interface in Composite Materials

点击翻译按钮获取中文摘要

The properties of fiber-reinforced composites are strongly dependent on interface mechanical properties. Thus, understanding of interface mechanical properties becomes an important subject of recent researches. Among the interfacial mechanical properties shear frictional resistance is important. The attention of this study has been focused on a new approach for evaluation of interface shear frictional resistance by introducing a real contact area at a frictional sliding interface. The study involves (1) effect of interface roughness on shear frictional resistance, (2) quantitative analysis of interface shear frictional resistance using a real contact area approach, and (3) application of the real contact area for engineering composite.The effect of interface roughness on shear frictional resistance is examined using model composites. Fibers with a different surface roughness are incorporated into an epoxy matrix and the interface shear frictional resistance is evaluated by push-out and push-back tests. The result shows strong dependence of interface shear frictional resistance on the profile of surface roughness at frictional sliding interface. The real contact area analysis is introduced to evaluate shear frictional stress, and the analysis gives quantitative understanding of shear frictional resistance. The interface shear frictional resistance, τィイD2sィエD2, is expressed as τィイD2sィエD2=(AィイD2rィエD2/AィイD2aィエD2)・τィイD20ィエD2 where AィイD2rィエD2 and AィイD2aィエD2, respectively, are the real contact area and apparent contact area at frictional sliding interface, τィイD20ィエD2 is the intrinsic shear frictional resistance at the real contact area. This approach is applied to the evaluation of interface shear frictional resistance in AlィイD22ィエD2OィイD23ィエD2 fiber-reinforced AlィイD22ィエD2OィイD23ィエD2 matrix composite. The result indicates that the microstructural effect of the composite is successfully evaluated using a rear contact area approach.