Microstructure and performance of solid TC4 titanium alloy subjected to the high pulsed magnetic field treatment

Abstract

The effect of high pulsed magnetic field with different magnetic induced intensity (B) on the microstructure and mechanical performance of solid TC4 titanium alloy was investigated. The microstructure morphology was characterized by metallographic microscope, scanning electronic microscopy and transmission electronic microscopy. The results show that the magnetic has induced the phase transformation from β to α. At 4T the volume fraction of α phase has increased from 49% (B=0) to 59%. Meanwhile, compared to that of original sample the dislocation density at 3T is 4.8 times, which was the result of magneto-plasticity effect. However, the dislocation density will not always increase with B due to the dislocation pile-up effect. The mechanical properties tests show that the strength of materials is enhanced with the B increase within a certain scope. The strength and elongation of processed TC4 alloy exhibit the obvious changes: when B=3T the maximum strength reaches 1330MPa which ascribes to the dislocation strengthening. It is enhanced by 7.6% compared to that of original sample. It is noted that when B=4T the strength and toughness are improved simultaneously which are attributed to not only the dislocation strengthening but also the amount, distribution and morphology of α phase.