Potential of duplex plasma deposition processes for the improvement of wear resistance of hot forging dies

The efficiency offorging processes is significantly influenced by the tool and scrap costs whichin their turn depend on the life time of forging dies. The tools used for hotforging are subject to process-related high mechanical, tribological, chemicaland thermal-cyclic loads which usually interact with each other. In comparisonto other manufacturing methods, the resulting load spectrum leads to extensivewear and thus to the failure of forging dies after a short tool life. Toincrease the wear resistance of forging dies, duplex treatments consisting ofplasma nitriding and plasma deposition techniques were used to improve thesurface properties and hence to increase the die life time. By basicinvestigation of the wear mechanisms the potentials of newly developed vanadiumdoped chromium nitride and boron containing titanium nitride coating systemswere investigated. Within the presented work it is demonstrated that vanadium-dopedchromium nitride layers have a high wear reduction potential for hot forgingdies.