Abstract:The microstructure and properties of short alumina fiber reinforced Al-1.5Mg composite(Al₂O₃sf/Al-1.5Mg) manufactured by extrusion directly following liquid infiltration (EDFLI) were experimentally investigated.It was found that the microstructure of Al₂O₃sf/Al-1.5Mg composite is characterized by a well-densified matrix,with fine recrystallized grains and free from microvoids and non-wetting defects,and quite uniformly and quasi unidirectionally distributed fibers maintaining adequate aspect ratios,which leads to a better strengthening effect.It was also found that the mechanical properties E,σ_0.2,σ_b and the thermal expansion resistance of the composite simultaneously increase with the enhancement of the fiber volume fraction while the elongation δ is still maintained at a relative high level.Besides,the Al₂O₃sf/Al-1.5Mg composite possesses corrosion resistance equivalent to that of the Al-1.5Mg alloy.

Key words: Al₂O₃sf/Al-1.5Mg composite microstructure properties extrusion infiltration