Friction stir processing (FSP) can play an important role in grain refinement, redistribution of second phase and texture evolution. In this study, different rotation speed was employed during FSP to process Mg-Zn-Nd (ZN20) alloy with different grain size, texture and distribution of second phase. Immersion test combined with observation on corrosion morphology was carried out to evaluate the corrosion resistance of ZN20 alloy. After FSP, grain size in the alloy could be refined to 4 μm owning to dynamic recrystallisation, the volume fraction of second phase decreased as the rotation speed increased under the influence of heat input, and strong basal texture could be formed. Finer grain size could play a positive role in improvement of the corrosion resistance by stabilising the corrosion product and acting as a barrier for corrosion cracking. Less second phase and strong basal texture cloud improve the corrosion resistance by reducing the corrosion pits.

搅拌摩擦加工（FSP）在晶粒细化，第二相的重新分布和织构的演变中可以发挥重要作用。在这项研究中，在FSP过程中采用了不同的转速来处理具有不同晶粒尺寸，织构和第二相分布的Mg-Zn-Nd（ZN20）合金。进行了浸没试验和腐蚀形态观察相结合的评估，以评价ZN20合金的耐腐蚀性。FSP后，由于动态再结晶，合金中的晶粒尺寸可以细化到4μm，在热输入的影响下，第二相的体积分数随着转速的增加而减小，并且可以形成牢固的基础组织。更细的晶粒尺寸可以通过稳定腐蚀产物并充当腐蚀裂纹的屏障，在提高抗腐蚀性能方面发挥积极作用。