报告人：Prof. Zhihe Jin (University of Maine,USA)
报告一：Effect of Interfacial Thermal Resistance on Surface Cracking in a Coating Layer Bonded to a Substrate
报告一简介: The first part of this seminar is concerned with the thermal fracture of bonded dissimilar materials considering interfacial thermal resistance. It is known that thermal resistance exists at interfaces in bonded dissimilar materials due to imperfect mechanical and chemical bonding as well as phonon scattering at the interface. This thermal resistance influences the temperature distribution as well as thermal stresses in the bonded materials. We consider an edge crack in the coating layer that is bonded to a substrate. The thermal stress intensity factor for the edge crack considering the thermal resistance at the coating-substrate interface is calculated using an integral transform/integral equation method. The numerical results for an Al2O3 coating on a Si3N4 substrate show that the thermal stress field deviates from that for the coating/substrate system without considering interfacial thermal resistance. The thermal stress intensity factor is increased by the interfacial thermal resistance, which indicates that the thermal shock resistance of the coating/substrate system can be degraded by the presence of thermal resistance at the interface between the coating and substrate.
报告二：A Matricity-Based Thermal Conductivity Model with Application to Thermal Fracture of Interpenetrating Phase Composites
报告二简介: The second part of this seminar is concerned with thermal fracture of interpenetrating phase composites (IPCs) using a matricity-based thermal conductivity model. A matricity-based thermal conductivity model for IPCs is first developed. The model employs the formulas of effective thermal conductivities for particulate composites together with the so-called matricities of the constituent phases. The model is then applied to investigate a double edge cracked plate of a ceramic/metal IPC under a thermal shock. The numerical results for an Al2O3/aluminum IPC show that both the peak tensile thermal stress and the peak thermal stress intensity factor (TSIF) are significantly lower than those for the corresponding aluminum particulate Al2O3-matrix composite.
报告人简介：Dr. Zhihe Jin is a Professor in the Department of Mechanical Engineering at the University of Maine. He received his B.S. in Mechanics from Lanzhou University in 1982, and his Master’s and Doctoral degrees in Engineering Mechanics from Tsinghua University in 1985 and 1988, respectively. He worked at Northern Jiaotong University, Shizuoka University, University of Sydney, Virginia Tech, University of Illinois and Purdue University before joining the University of Maine in 2005. Dr. Jin is a Fellow of ASME, and was a JSPS Invitation Fellow in 2016. He has published more than 100 refereed journal papers and a book on fracture mechanics.