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The tensile tests of TC4 alloy are carried on electronic universal testing machine in the synchronous presence of high pulsed magnetic field (HPMF) parallel to the axial direction. The effects of magnetic induction intensity (B = 0, 1 T, 3 T, and 5 T) on elongation (δ ) of TC4 alloy are investigated. At 3 T, the elongation arrives at a maximum value of 12.41%, which is enhanced by 23.98% in comparison with that of initial sample. The elongation curve shows that 3 T is a critical point. With B increasing, the volume fraction of α phase is enhanced from 49.7% to 55.9%, which demonstrates that the HPMF can induce the phase transformation from β phase to α phase. Furthermore, the magnetic field not only promotes the orientation preference of crystal plane along the slipping direction, but also has the effect on increasing the dislocation density. The dislocation density increases with the enhancement of magnetic induction intensity and the 3-T parameter is ascertained as a turning point from increase to decrease tendency. When B is larger than 3 T, the dislocation density decreases with the enhancement of B. The influence of magnetic field is analyzed on the basis of magneto-plasticity effect. The high magnetic field will enhance the dislocation strain energy and promote the state conversion of radical pair generated between the dislocation and obstacles from singlet into triplet state, in which is analyzed the phenomenon that the dislocation density is at an utmost with B = 3 T. Finally, the inevitability of optimized 3-T parameter is further discussed on a quantum scale.

In order to explore the dependence of plasticity of metallic material on a high magnetic field, the effects of the different magnetic induction intensities (𝐻 = 0 T, 0.5 T, 1 T, 3 T, and 5 T) and pulses number (N = 0, 10, 20, 30, 40, and 50) on tensile strength (σ b ) and elongation (δ ) of 2024 aluminum alloy are investigated in the synchronous presences of a high magnetic field and external stress. The results show that the magnetic field exerts apparent and positive effects on the tensile properties of the alloy. Especially under the optimized condition of 𝐻 * = 1 T and N * = 30, the σ b and δ are 410 MPa and 17% that are enhanced by 9.3% and 30.8% respectively in comparison to those of the untreated sample. The synchronous increases of tensile properties are attributed to the magneto-plasticity effect on a quantum scale. That is, the magnetic field will accelerate the state conversion of radical pair generated between the dislocation and obstacles from singlet to the triplet state. The bonding energy between them is meanwhile lowered and the moving flexibility of dislocations will be enhanced. At 𝐻 * = 1 T and N * = 30, the dislocation density is enhanced by 1.28 times. The relevant minimum grain size is 266.1 nm, which is reduced by 35.2%. The grain refining is attributed to the dislocation accumulation and subsequent dynamic recrystallization. The ( 211) and ( 220) peak intensities are weakened. It is deduced that together with the recrystallization, the fine grains will transfer towards the slip plane and contribute to the slipping deformation.

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