Application of the Chemomechanical Effect in Drawing Alloys with Low Plasticity

This review provides a brief theoretical basis for the electrochemical plasticization of metals during plastic deformation and summarizes the results of large-scale laboratory experiments on cold drawing of various alloys. Simultaneous action of anodic polarization and plastic deformation during cold drawing effectively promotes the softening of the surface layer of metals due to the chemomechanical effect. This action creates favorable conditions for multiple slip and destruction of pile-ups and also causes an additional flow of dislocations, leading to a softening of the surface and a decrease in the drawing force during electrochemical drawing (ECD) compared to drawing in air (DIA). The drawing force is the smallest and the softening degree is the largest in aqueous solutions of sulfuric acid, in which the corrosion rate is high, and surface layer dissolves uniformly. The softening degree during ECD, as compared to DIA, gradually decreases as the drawing speed increases due to the reduction in the time required for most reactions and reagent transfer. As the number of passes through the die is increased, the softening effect in ECD compared to DIA can increase or decrease depending on the drawing speed and hardness of the metal.