The aluminum matrix composites(AlB2+a-Al2O3)/Al were fabricated by in situ reaction synthesis from an Al-B2 O3 system. The reaction pathways, apparent activation energies and tensile properties were analyzed by using ...The aluminum matrix composites(AlB2+a-Al2O3)/Al were fabricated by in situ reaction synthesis from an Al-B2 O3 system. The reaction pathways, apparent activation energies and tensile properties were analyzed by using differential scanning calorimetry(DSC), X-ray diffraction(XRD), scanning electron microscopy(SEM), and equipped energy dispersive spectroscopy(EDS). The results showed that there are two-step reactions in the Al-B2 O3 system. The first-step is 15 Al+7 B2 O3→7 aAl2O3+AlB12+2 B and the second-step is 2 B+AlB12+6 Al→7 AlB2. Their corresponding apparent activation energies are 352 and 444 kJ/mol, respectively. The tensile strength and elongation rate of the composites are 190.5 MPa and 6.6%, respectively.Compared with ordinary aluminum base material, the performance is superior. There are many dimple and cracked a-Al2O3 reinforcements in tensile fracture surface layer.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.51571118 and 51371098)Natural Science Foundation of Jiangsu Province(No.BK20141308)
文摘The aluminum matrix composites(AlB2+a-Al2O3)/Al were fabricated by in situ reaction synthesis from an Al-B2 O3 system. The reaction pathways, apparent activation energies and tensile properties were analyzed by using differential scanning calorimetry(DSC), X-ray diffraction(XRD), scanning electron microscopy(SEM), and equipped energy dispersive spectroscopy(EDS). The results showed that there are two-step reactions in the Al-B2 O3 system. The first-step is 15 Al+7 B2 O3→7 aAl2O3+AlB12+2 B and the second-step is 2 B+AlB12+6 Al→7 AlB2. Their corresponding apparent activation energies are 352 and 444 kJ/mol, respectively. The tensile strength and elongation rate of the composites are 190.5 MPa and 6.6%, respectively.Compared with ordinary aluminum base material, the performance is superior. There are many dimple and cracked a-Al2O3 reinforcements in tensile fracture surface layer.
