Effect of Solution and Aging Treatment on Microstructure and Impact Properties of TC11 Titanium Alloy

TC11 titanium alloy was treated by solution and aging. The relationship between microstructure and impact property of the alloy after different treatments was studied by optical microscope, XRD and impact property test. The results show that after solution treatment at 955 degrees C, the microstructure of the alloy is composed of alpha(p) phase and alpha'' phase, and the morphology of alpha(p) phase is mainly equiaxed and strip-like. After solution treatment at 1015 degrees C, the microstructure is composed of alpha' phase and alpha'' phase, and the morphology of alpha' phase is fine needle-like. After aging treatment of the alloys under two groups of solution conditions, beta(T) appears in the microstructure, and alpha(s) phase is precipitated. The maximum impact toughness of the alloy is 22 J/cm(2) after solution treatment at 955 degrees C. After aging treatment, the impact toughness of the two groups of alloys decreases with the increase in aging temperature. When the solution temperature is 955 degrees C, the fracture morphology shows ductile fracture characteristics. After aging treatment, secondary cracks appear in the fracture morphology. When the solution temperature is 1015 degrees C, the fracture morphology shows brittle fracture characteristics. After aging treatment, the fracture morphology exhibits holes in addition to secondary cracks.