The mechanical properties of the near-alpha titanium alloys Ti6242 alloy disc forgings usually have close relationship with the original microstructure of bars. In this study

three kinds of Ti6242 alloy bars with different original microstructure were selected to quantitatively analyze the difference and evolution of different microstructure characteristics

including the forged state

the solid solution state and the solid solution and aging state. The effects of the microstructure difference and evolution on the mechanical properties were also compared. The results showed that the differences of primary α phase volume fraction reduced after similar solid solution and aging treatment process

while the sectional area distribution and shape distribution of primary α phase still retained some differences. Room temperature tensile mechanical properties showed no significant difference

while the low fatigue property and dwell fatigue property exhibited significant difference. According to the microstructure difference analysis and mechanical property results

the original microstructure of bar with fine

non-equiaxed and no obvious orientation primary alpha phase contributed to good fatigue properties.