The Effect of Heat Treatment System on Mechanical Properties of Titanium Alloy BTi-6554

The effects of solution and aging treatment on the mechanical properties of BTi-6554 alloy titanium were investigated. The results showed: As to βsolution and aging treatment, the increase of fracture toughness is quite conspicuous as the solution temperature was raised, but the change of strength and plasticity is not obvious; As to (α+β) solution and aging treatment, the decline of fracture toughness and plasticity is quite conspicuous as the solution temperature increased, but the strength increased. The strength of (α+β) solution and aging treatment is higher than that of βsolution and aging treatment, but the fracture toughness is relatively lower. As the aging temperature increased, the strength of the alloy gradually decreased, but the plasticity and fracture toughness gradually improved and the improvement of fracture toughness is quite conspicuous. A better combination of strength-toughness-ductibility could be obtained under the heat treatment as solution at 900~930 oC and aging treatment at 560~590 oC.