Powder mixture of pure A1 and oxidized SiC was consolidated into 10% (mass fraction) SiCp/AI composites at 523 K by equal channel angular pressing and torsion (ECAP-T). The interfacial bonding of the composites wa...Powder mixture of pure A1 and oxidized SiC was consolidated into 10% (mass fraction) SiCp/AI composites at 523 K by equal channel angular pressing and torsion (ECAP-T). The interfacial bonding of the composites was characterized by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The selected area electron diffraction (SAED) for the interface was investigated. The elements at the interface were scanned by energy dispersive spectroscopy (EDS) and the EDS mapping was also obtained. X-ray diffraction (XRD) analysis was carried out for the composites fabricated by 1 pass, 2 passes and 4 passes ECAP-T. According to the XRD analysis, the influences of ECAP-T pass on the Bragg angle and interplanar spacing for AI crystalline planes were studied. The results show that after ECAP-T, the interface between A1 and SiC within the composites is a belt of amorphous SiO2 containing a trace of A1, Si and C which diffused from the matrix and the reinforcement. With the growing ECAP-T pass, the Bragg angle decreases and interplanar spacing increases for A1 crystalline planes, due to the accumulated lattice strain. The increasing lattice strain of A1 grains also boosts the density of the dislocation within A1 grains.展开更多
A two-phase elasto-plastic material is investigated. It is shown that, if the interface is modeled as the limit of a vanishing layer of a third material, then the resulting two-phase material will exhibit a smaller in...A two-phase elasto-plastic material is investigated. It is shown that, if the interface is modeled as the limit of a vanishing layer of a third material, then the resulting two-phase material will exhibit a smaller interracial dissipation than that of a pure two- phase model.展开更多
基金Project(51175138) supported by the National Natural Science Foundation of ChinaProjects(2012HGZX0030,2013HGCH0011) supported by the Fundamental Research Funds for the Central Universities,China
文摘Powder mixture of pure A1 and oxidized SiC was consolidated into 10% (mass fraction) SiCp/AI composites at 523 K by equal channel angular pressing and torsion (ECAP-T). The interfacial bonding of the composites was characterized by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The selected area electron diffraction (SAED) for the interface was investigated. The elements at the interface were scanned by energy dispersive spectroscopy (EDS) and the EDS mapping was also obtained. X-ray diffraction (XRD) analysis was carried out for the composites fabricated by 1 pass, 2 passes and 4 passes ECAP-T. According to the XRD analysis, the influences of ECAP-T pass on the Bragg angle and interplanar spacing for AI crystalline planes were studied. The results show that after ECAP-T, the interface between A1 and SiC within the composites is a belt of amorphous SiO2 containing a trace of A1, Si and C which diffused from the matrix and the reinforcement. With the growing ECAP-T pass, the Bragg angle decreases and interplanar spacing increases for A1 crystalline planes, due to the accumulated lattice strain. The increasing lattice strain of A1 grains also boosts the density of the dislocation within A1 grains.
文摘A two-phase elasto-plastic material is investigated. It is shown that, if the interface is modeled as the limit of a vanishing layer of a third material, then the resulting two-phase material will exhibit a smaller interracial dissipation than that of a pure two- phase model.