Studies of lubricants and punch design in punching of stainless steel

Environmentally hazardous lubricants such as chlorinated paraffin oils are often applied in punching and blanking operations especially involving stainless steel workpiece materials. This is due to the fact that punching and blanking are among the tribologically most difficult forming operations caused by creation of virgin workpiece surfaces in contact with the tool surface and the difficult access of lubricant to the tool/workpiece interface.

In order to develop alternative lubricants that may substitute the existing hazardous lubricants often used in industry, appropriate tests are greatly needed. In this paper such a lubricant test for punching and blanking is proposed and results from applying the test for evaluating different lubricants for punching are presented.

Studies of lubrication mechanisms in punching and blanking are furthermore presented showing the influence of the punch stem topography.