In this work, the effect of drawing pass on the surface layer softening or plasticizing of Q235 steel bar during electrochemical cold drawing (ECD) was studied, as well as cold drawing in air (DIA) for comparison. The results indicate that the softening or plasticizing degree gradually decreases with increasing drawing pass. The reason for this should be that dislocations generated in surface layer are only partially overflowed from the surface in the form of additional dislocation flux. The general dislocation density thereby gradually increases with the increase in drawing pass, resulting in the increase in the work hardening degree of the surface layer, and thus, the drawing stress. In this case, the texture orientation of the bar surface layer is gradually enhanced. In contrast, the dislocation density, and thus the work hardening degree of DIA bar, are higher than those of the ECD partner, resulting in larger drawing stress. ECD can obtain a product with excellent comprehensive mechanical properties compared with DIA, and there are no cracks on the fracture surface of ECD bar drawn for at least seven passes.

中文翻译：

---

拉拔道次对Q235钢筋电化学冷拔过程中软化或塑化的影响

在这项工作中，研究了拉拔道次对Q235钢筋表面层软化或塑化的影响，以进行电化学冷拔（ECD）以及空气冷拔（DIA）进行比较。结果表明，随着拉伸次数的增加，软化或塑化度逐渐降低。其原因应该是在表面层中产生的位错仅以额外的位错通量的形式从表面部分溢出。由此，总的位错密度随着拉拔道次的增加而逐渐增加，导致表面层的加工硬化度增加，从而拉拔应力也增加。在这种情况下，条形表面层的纹理取向逐渐增强。相反，位错密度 因此DIA bar的加工硬化程度高于ECD合作伙伴，从而导致更大的拉拔应力。与DIA相比，ECD可获得具有优异综合机械性能的产品，并且至少经过7次拉伸后，ECD钢筋的断裂表面上没有裂纹。