Abstract
Traditional methods of relief coating - chroming - have been used to increase the coining die lifetime for many years. This article is aimed at the quality evaluation of Cr layer on the coining dies surfaces. Three specimens – coining dies – were dipped in the electrolyte at different intervals of time. The quality and thickness of the Cr layer were examined and evaluated. The results were then compared with results of the reference coining die, which achieved the optimum of lifetime (represented in number of coins per minute).

Key words
coining dies, Cr layer, technological process of coating, coating time, quality and reliability, lifetime

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