TiAl/B4C composite fabricated by high energy ball milling and hot press sintering processes and its mechanical properties

In situ homogeneous Ti–Al alloy and particulate reinforced B4C composite were obtained by fabricating Ti, Al, and B4C via high energy ball milling and subsequent hot press sintering. These technical processes promoted the solid reactions among B4C, Ti, and Al to produce composites comprising Ti–Al, TiC, TiB2, and B4C. When the starting materials were 10 wt.% TiAl/B4C and 20 wt.% wt.%TiAl/B4C, TiAl layers were intercalated into the ceramics substrate; further increasing in Ti and Al content (30 wt.% and 40 wt.%), the Ti–Al alloy was agglomerated and covering on the surfaces of the carbide and boride ceramics. The relative density increased while the hardness decreased with the enhancement of the total content of Ti and Al in the composite. The 20 wt.% TiAl/B4C composite exhibited both novel fracture toughness and the best bending strength.

Research highlights▶ TiAl/B4C was made by high energy ball milling together with hot press sintering. ▶ The composite comprised TiAl, TiC, TiB2, and B4C. ▶ It showed excellent mechanical properties in bending strength and fracture toughness.