Effect of high pulsed magnetic field on microstructure and mechanical properties of TC4 titanium alloy

The effects of magnetic induced intensity (B=2T, 3T and 4T) on the microstructure and mechanical properties of TC4 titanium alloy in the condition of high pulsed magnetic field (HPMF) were investigated. The results show that the volume fraction of α phase increases from 49% to 59% when B increases from 2T to 4T, which demonstrates that the HPMF can induce the phase transformation from β to α phase. After the HPME treatment, the dislocation density increases. The dislocation density reaches a maximum when B=3T, which is added by 4.8 times compared to that without HPMF treatment. When B=4T, the dislocation density decreases a bit. The phenomenon is ascribed to the combined effects of magnetoplasticity and dislocation piles-up. Meanwhile, the tensile strength increases due to HPMF treatment. When B=3T, the tensile strength is 1330 MPa, which increases by 7.6% compared to that without treatment. When B=4T, the tensile strength and amplification are 1265 MPa and 2.3%, respectively. And the elongation is 15.66% which increases by 4.8% compared to that without treatment. Therefore, the strength and elongation increases synchronously, which is the result of dislocation strengthening mechanism and the amount, distribution and morphology of α phase. ©, 2015, Central South University of Technology. All right reserved.