Tailorable microstructure and mechanical properties of selective laser melted TiB/Ti–6Al–4V composite by heat treatment
Jinliang Zhang, Bo Song, Chao Cai, Lijun Zhang, Yusheng Shi
Abstract
This paper systematically investigated the effect of solution and artificial aging heat treatments on the microstructural evolution and mechanical properties of TiB/Ti–6Al–4V composites in situ fabricated by selective laser melting. The results showed that the fully martensite microstructure with TiB clusters of the as-built samples was transformed into lamellar α+β microstructure with TiB strips after solution heat treatment. With increasing the temperature, the α laths and TiB particles coarsened and the β volume fraction increased. After aging heat treatment, β volume fraction decreased and TiB had no obvious changes. A superior combination of the yield strength of (1146.8±28.2) MPa and even higher plasticity and ultimate compressive strength ((1680.1±18.3) MPa) than the as-built ones was obtained by solution heat treatment at 1000°C + water quenching and aging at 600°C for 6 h + air cooling.