Al matrix composite reinforced by hexagonal boron nitride (h-BN) with nearly full densification was
successfully fabricated by the semi-solid powder metallurgy technique.The h-BN/Al composites were
synthesized with elemental pure Al powder size of d50¼ 35, 12 and 2 μm. The powder morphology and
the structural characteristics of the composites were analyzed using X-ray diffraction,scanning and
transmission electron microscopy.The density,Brinell hardness and compressive behavior of the samples
were characterized.Density measurement of the Al composites revealed that the composite densification
can be effectively promoted by plenty of embedded liquid phase under pressure.Composites prepared
using Al powder with varying granularity showed different grain characteristics,and insitu recrystallization occur redinside the original grains with35 μm Al powder.A sharp interface consisting of
Al/Al2O3/h-BN was present in the composites. Both the compressive strength and the fracture strain of
the investigated composites increased with the decrease of the Al powder size,along with the Brinell
hardness. The composite with2 μm Al powder exhibited the highest relative density(99.3%), Brinell
harness (HB128),compressive strength(763MPa) and fracture strain(0.299).