New multifunctional PVD-coating in the material system Cr–BCN–Si for steel sheet forming

In the present work a new multifunctional PVD Cr–BCN–Si thin film has been developed. Properties like hardness (2900 HV0.05), adhesion (48 N critical load), coefficient of friction (0.14…0.22) and structural constitution (amorph except for CrN) have been estimated. Furthermore the new coating has been tested in the steel-strip-drawing-test. Three different qualities of steel sheets (zinced, electrolytically zinced and electrolytically zinced and phosphated) and two different lubricants (Fuchs RP4107S and PL3802-39S) were tested. The new coating has been compared to a TiN reference coating which has been selected out of five well known hardcoatings, which have been deposited on five different qualities of tool steel (1.2320, 1.2358, 1.2379, 1.3343, Vanadis6). Also the new coating has been tested in a new model forming process and the results were compared to the results with the TiN reference coating. ing tool for car manufacturing coated with the new Cr–BCN–Si multifunctional PVD thin film and also coated with the TiN reference coating shows excellent behaviour under real production conditions. For the first time a PVD-coated forming tool shows a good lifetime performance which is normally observed only for CVD-coated forming tools.