Papers by Author: Jian Kang Chen

Abstract: The effect of loading of stainless steel fiber (SSF) and temperature on electrical resistivity of SSF/PA6 conductive polymer composites was investigated in this paper. The distribution of fibers in the composites was observed by means of scanning electron microscopy（SEM）. The experimental results show that the resistivity decreases closely along with the increase of SSF loading from 0 to 12 Wt. % and temperature from 20 to 200°C. It is shown by SEM that the fibers are dispersed homogeneously in the polyamide-6 matrix.

Abstract: The debonding of a rigid particle embedded in an infinite non-linear viscoelastic material is investigated in this paper. Under sphere-symmetric deformation, a non-linear equilibrium equation expressed by velocity of a particle in the viscoelastic matrix material is derived. The strain rate is obtained by solving non-linear equation in terms of iterative method. According to the energy criterion, the critical instant of the interfacial debongding is calculated. Numerical results show that the influence of non-linear viscosity on the interfacial debonding is significant.

Abstract: Statistical evolution of microvoids in a particle-filled polymer under plate impact is theoretically studied. Based on the constitutive equations of the material recently obtained by the authors, the velocity of the propagation of one-dimensional strain wave caused by the plate impact is analyzed, and the evolution of the microdamage is calculated. It is shown that the microvoid evolution is influenced by several factors, such as particle size-dispersity, average radius of particles, and the adhesive energy of the interface. The numerical results show that there is a sensitive crest of the impact velocity for microvoid evolution. If the impact velocity reaches the critical value corresponding to the peak value of the crest, the microvoids accumulation will increase rapidly, and it may lead to the dynamic failure of the material.