Multi-phase alloy steel, preparation method thereof and vehicle part

The invention relates to multiphase alloy steel, a preparation method thereof and a vehicle part, and the multiphase alloy steel comprises the following components in percentage by mass: 0.08%-0.12% of C, 0.1%-0.5% of Si, 1.4%-2.1% of Mn, less than or equal to 0.015% of P, less than or equal to 0.006% of S, 0.01%-0.04% of Al, 0.01%-0.04% of Nb, 0.01%-0.04% of Ti and the balance of Fe and inevitable impurities. By controlling the proportion of all specific components in the multi-phase alloy steel, the multi-phase alloy steel has excellent tensile strength, excellent plasticity and excellent bending performance. 本发明涉及一种多相合金钢及其制备方法、车辆零部件，按照质量百分数计，所述多相合金钢的组分包括：0.08%~0.12%C、0.1%~0.5%Si、1.4%~2.1%Mn、P≤0.015%、S≤0.006%、0.01%~0.04%Al、0.01%~0.04%Nb、0.01%~0.04%Ti、余量为Fe和不可避免的杂质。本申请通过控制多相合金钢中各特定组分的配比，从而使多相合金钢兼具优异的抗拉强度、优良的塑性和优异的弯曲性能。