Effect of current pulses on the drawing stress and properties of Cr17Ni6Mn3 and 4J42 alloys in the cold-drawing process

Current pulses (approximately 103 A/mm2 for about 20 μs) have been applied to the drawing process of Cr17Ni6Mn3 and 4J42 (42Ni–56Fe) alloyed wire, the drawing stress being found to be decreased significantly. Furthermore, the ultimate tensile strength σb was decreased and the elongation ratio δ (%) was increased with the application of the current pulses. In this experiment, the wire-drawing velocity of Cr17Ni6Mn3 was increased from 9 m/min to about 60 m/min, latter being the actual wire-drawing velocity employed in the factory. With the data of the magnetic properties of the Cr17Ni6Mn3, it was found that the saturated magnetization Bs and the residual magnetization Br had decreased with the application of the current pulses. On the other hand, with the increase of the drawing speed, the decrease of the drawing stress had reduced, which accorded with the data of magnetic properties. Thus, the frequency of the current pulses should be increased with the increase of the wire-drawing velocity so as to ensure the electroplastic effect.