Papers by Author: Jin Xiang Wang

Abstract: To improve understanding of explosive welding and relate the effect of the process variables on the physical parameters, the smooth particle hydrodynamics (SPH) method in the LS-DYNA 12.0 finite element program was adopt to simulate the process of two-layer steel explosive welding. Temperature field near the stagnation point was calculated according to the work-heat transfer theory. Finally, the formation mechanism of the interface wave was analyzed under the condition that strain field, temperature field etc. were considered. The results show that: the phenomenon of jetting and the interfacial waves observed in explosive welding were quite well reproduced in these simulations; the changing collision angle with propagation distance is directly responsible for the change in interface morphology from wavy to smooth at the welding front; the maximum stress ,strain and temperature are localised at the wavy interface zone; the maximum temperatures near the interface will be high enough under proper conditions and this will be helpful for the formation of the jet and the wavy interface.

Abstract: The metallic glass particles reinforced aluminum matrix composites without obvious defects were obtained successfully by explosive compaction of mixed powders. The quasi-static compressive mechanical properties of the composites with the reinforcement matrix mass fraction 10%, 15% and 20% respectively were researched recur to universal testing machine of Instron 3367 and self-consistent theory. Finally, reinforcement mechanism of the metallic glass particles on the matrix was analyzed by numerical simulation recur to LS-DYNA program. The results show that the mechanical properties obtained by self-consistent theory are well accord with the experimental results; compared with pure aluminum, the yield stress of the composites with metallic glass particles reinforcement of the mass fraction 20% enhances 46.8 percent; the main reinforcement mechanism is the amorphous particles can undertake higher loading, the combined quality of the reinforcement particles with the matrix and the distribute uniformity of the reinforcement particles are important factors which will affect the reinforcement effects.

Abstract: In this paper the metallic glass particles reinforced aluminium matrix composites without obvious defects were obtained successfully by explosive compaction of mixed powders. The mass fraction of the amorphous phase is 10%, 15% and 20% respectively in the specimens. The scaning electric microscope micrographs of the composites show that the metallic glass particles are uniformly distributed in the matrix. The x-ray diffraction and differential thermal analysis of the composite specimens show that the amorphous phase is maintained in the composites without crystallization during the compaction. Finally the influences of macro-temperature rise and micro-heat transfer on the crystallization were analyzed.