method for the cold working of mechanical product in a form with high ratio of height to thickness.

摘要

To prevent galling during the drawing and ironing process, black plate is provided with an economical coating for improving surface lubricity. Cold-reduced strip is rinsed with a solution containing soluble salts of manganese and sulfur, e.g. MnSO4; the strip is dried and then heated to above 800 DEG F in a reducing atmosphere, such as HNX. Heating is conducted at a temperature sufficient to reduce the sulfates and provide a surface coating of MnS in which the surface sulfur concentration is in excess of 0.5%.