Effect of aspect ratios of in situ formed TiB whiskers on the mechanical properties of TiBw/Ti–6Al–4V composites

Ti alloy matrix composites reinforced with nanosized TiB whiskers (TiBw/Ti–6Al–4V) were synthesized through an in situ reaction between TiB2 and Ti–6Al–4V powders during a spark plasma sintering process. The TiBw/Ti–6Al–4V composites reinforced by whiskers with an aspect ratio of 58 exhibited threefold greater strengthening efficiency compared to those reinforced by whiskers with low aspect ratios. It was determined that the strengthening originates from the high load-bearing capability of TiB whiskers with a diameter of 100 nm formed in situ in a Ti alloy matrix.