Performance of hard coated steel tools for steel sheet drawing
In the present work five different hard coatings have been deposited on five qualities of tool steel by different means of deposition (CVD, PVD, Arc). Substrates were highly polished planar steel samples, on the one hand, and special testing-tools on the other hand. Planar steel substrates were used to set up a datatable of thin film characteristics such as film thickness, hardness, coefficient of friction, adhesion and Young's modulus. Coated testing-tools were used to evaluate their performance in the `steel-strip-drawing-test'. This testing routine is explained in detail. Three different qualities of steel sheets and two different lubricants were tested. In order to evaluate the compatibility of a hard coated tool for steel sheet drawing two criteria from the `steel-strip-drawing-test', the coefficient of friction and the stick-slip-effect, were estimated.