Study on semidry/dry wire drawing using DLC coated dies

In the application of drawing in recent years, from the viewpoints of the reduction of environmental burden, improvement of hygiene of labor environment and reduction of production costs, the following actions are necessary; the reduction of the amount of drawing lubricant used, the replacement of currently used lubricants with environmentally friendly lubricants, the reduction of costs for the washing of lubricant adhering to products and the disposal of used lubricant. In this research, we explored methods for the realization of semidry and dry drawing in order to resolve the above issues. As a result of the findings, we studied drawing using a roller die and transverse directional ultrasonic vibration drawing using a bisected die developed by the authors. We also investigated the effect of diamond-like carbon (DLC) coating on the dies. In other words, the possibilities of the realization of semidry drawing with the use of a wash-free lubricant (i.e. lubricant which needs no particular removal process after drawing) and of completely dry drawing were studied by coating the die with DLC in addition to the use of measures considered to be effective for realizing semidry and dry drawing. As a result of this study, it is concluded that the drawing method utilizing the DLC-coated roller die and the transverse ultrasonic-vibration drawing using a DLC-coated bisected die are effective in realizing semidry and dry drawing for aluminum materials.