Experimental and numerical qualification of morphology-property-correlations using the method of essential work of fracture (EWF) by the example of polymer blends

J积分、裂纹尖端张开位移（CTOD）、能量释放率G和基本断裂功（EWF）是评价延性材料断裂力学行为的不同方法。这些方法不像准静态拉伸试验那样适用于设计中的尺寸标注，但在局部破坏行为的情况下能够提供更准确的信息。了解材料的局部破坏机理是优化材料的必要条件。他们的结果也提供了定量值，但只能用于基于相同聚合物基质的不同改性材料之间的比较。通过改变对断裂行为有影响的材料改性和/或形态，可以优化材料。从申请人的观点来看，特别是断裂基本功的方法比其他方法更合适和易于使用，并且可以应用于纯聚合物、聚合物共混物以及颗粒和纤维增强的聚合物。相应地，在原子尺度上模拟材料的力学性能还不能为设计提供尺寸参数，如准静态拉伸试验所做的那样，但在局部检查中相当准确。申请人认为这对于预测基本断裂功和优化用于不同应用的聚合物共混物是有用的。在这个计划的研究项目中，不同的改性对所研究的聚合物共混物的影响将用断裂基本功的方法来确定。同时，首次调整材料改性和测试方法，使其通过分子动力学模拟可预测。

The J-integral, the Crack-Tip-Opening-Displacement (CTOD), the energy release rate G and the method of the Essential Work of Fracture (EWF) are different methods to evaluate the fracture mechanical behavior of ductile materials. These methods are not suitable for dimensioning in design like the quasi-static tensile test, but are able to provide more accurate information in the case of local failure behavior. It is necessary to understand the local failure mechanisms to optimize materials. Their results offer also quantitative values, but can only be used for comparisons between different modified materials based on the same polymeric matrix. By varying the material modifications and/or morphology, which have an influence on the fracture behavior, materials can be optimized. From the applicants point of view, in particular the method of Essential Work of Fracture, is more appropriate and easy to use than the other methods and can be applied to neat polymers, polymer blends as well as particle and fiber reinforced polymers. Respectively, the simulation of the mechanical properties of materials at the atomic scale is not yet able to supply dimensioning parameters for the design, as the quasi-static tensile test does, but is pretty accurate at local inspections. The applicants regard this as useful to predict the Essential Work of Fracture and to optimize polymer blends for different applications. In this planned research project, the influence of different modifications on the investigated polymer blends will be determined with the method of Essential Work of Fracture. Simultaneously, the material modifications and the test method should be adjusted for the first time to make them predictable by means of molecular dynamics simulation.