Effect of Grain Boundary Alpha on Mechanical Properties of Ti5.4Al3Mo1V Alloy

The article brings out the correlation between the microstructure and mechanical properties of Ti5.4Al3Mo1V (VT14 alloy) highaEurostrength alpha beta titanium alloy. The specimens were solution treated above the beta transus temperature of the alloy (980A degrees C and 1000A degrees C) for 45 min and cooled at different rates (water quenched, air cooled, and furnace cooled) to ambient temperature. The specimens were polished, and the microstructural observations under optical microscopy resulted in a discontinuous alpha phase and a continuous network of alpha for 980A degrees C and 1000A degrees C beta-annealed conditions, respectively. Mechanical properties like tensile and impact were evaluated for a 980A degrees C beta-annealed condition. The fracture morphology features of failed impact specimens were compared with a mill annealed product. From the tensile strength data, it was observed that the strength achieved is maximum in the wateraEuroquenched condition (1291-1308 MPa) and lowest in the furnaceaEurocooled condition (895-905 MPa), whereas the impact strength is highest in the furnace-cooled condition (8.03-8.7 gm/cm(2)), which is comparable with the air-cooled condition (7.3-8.5 kg/cm(2)), and lowest for the water-quenched condition (2.5-3.1 kg/cm(2)). The current study is an attempt to correlate the mechanical properties to the heat treatment and thereby to the microstructure.