Effects of Mg content on aging behavior of sub-micron Al2O3p/Al-Cu-Mg composite
(1.黑龙江省哈尔滨市哈尔滨工业大学材料科学与工程学院
2.School of Materials Science and Technology, Harbin Institute of Technology, Harbin 150001, China
3.School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China
4.School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
2.School of Materials Science and Technology, Harbin Institute of Technology, Harbin 150001, China
3.School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China
4.School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
Abstract: 30%Al2O3p/Al-Cu-2.0Mg composite and Al2O3p/Al-Cu-2.5Mg composite with 0.3 μm-Al2O3 particles were fabricated. Age-hardening behaviors of two composites and the related matrix alloys were studied by means of Brinell-hardness measurement, DSC and TEM. The results show that the hardness of the composite is improved obviously because of the addition of sub-micron Al2O3 particles. But the hardness increment of Al2O3p/Al composite after aging is lower than that of the related matrix alloy. Moreover, the formation of GP region is suppressed by the addition of sub-micron Al2O3 particles, which broadens the exothermic peak of S′ phase. The increment of Mg content has a different influence on accelerating the aging processes of aluminum alloys and the composites, and the hardness also increases.
Key words: aluminum matrix composites; sub-micron Al2O3 particles; aluminum alloys; aging behavior