带缺陷流变性材料裂尖断裂过程区的热力学性和电磁性

THERMODYNAMIC CHARACTER AND ELECTROMAGNETIC NATURE OF THE FRACTURE PROCESS ZONE AT CRACK TIP IN RHEOLOGICAL MATERIAL WITH DEFECTS

带缺陷流变性材料破坏过程中显现出热致磁效应的实验结果表明：在材料破坏的过程中，由于内部温度梯度的存在，导致裂尖断裂过程区具有热致磁效应．可见，热传导方程应包括电磁场的贡献．这种情况意味着断裂过程区内的磁感应场变化，不是由磁通量守恒律的局部化剩余产生，而是本构关系的直接结果，它显示为非局部效应，并参与能量耗散，因此，材料的破坏过程不是纯粹的力学过程．本文应用线性算子谱论建立了条带型断裂过程区的流变场方程并讨论了其热力学关系．最后，以对于Galilei不变式是协变的Lorentz不变式方程分析了裂尖断裂过程区的电磁场特性．本文的成果将有利于金属基复合材料、导电聚合物、定向纳米材料等新型材料的设计和制造以及有关结构物的失效分析．

The experimental results of pyromagnetic effect revealed in the rupture process of rheological material with defects make known that:owing to the existence of internal temperature gradient leads to the occurrence of pyromagnetic effect in the fracture process zone at crack tip. It is thus clear that the equation of heat conduction should contains the contribution of electromagnetic field. This circumstance means that the variations of magnetic induction field in the fracture process zone are not due to the production of localization residual for the conservation law of magnetic flux,but a direct result of constitutive relation,it has manifested the non- localized effect, and participate in energy dissipation. Therefore, the rupture process of material is not a pure mechanical process. In this paper,the rheological field equation of striped fracture process zone is established by use the spectral theory of linear operators,and its thermodynamic relation are discussed. And finally, the nature of electromagnetic field is analyzed by the equation of Lorentz's invariant which is covariant with Galilei's invariant. The achievements of this paper are advantageous to the design and manufacture of new -type materials such as metal -base composites, conductive polymers, stereospecific nano-material ect. and to the failure analysis of the structure concered.