The potential of plasma deposition techniques in the application field of forging processes

High mechanical, chemical and thermal cyclic loads characterize the load regime of hot forging applications. Additionally these loads are acting simultaneously which leads to a failure of the form giving tool components after a short tool life. Accounting for about 70% of all causes, wear is the main reason for production downtimes. Other failure factors are thermal and mechanical cracks as well as plastic deformation as a result of the loss of hardness due to the high thermal charge. The caused production downtimes can be reduced by surface modifications of the tools. Different results of recent research works prove the high potential of newly developed PVD and PECVD coating systems regarding the reduction of die wear. CrVN coating systems developed by PVD coating equipment and boron containing multilayered PECVD coating systems were applied to forging dies. Basic investigations of the occurring wear mechanisms show the qualification of the coating systems which have to be adapted to the decisive process related loads and damages.