The objective of this thesis is the increase of the quality of the hard metal-scrap recycled via the zinc process. The direct recycling of these scraps only allows the disintegration through deterioration of the binder by formation of an intermetallic compound with zinc. Subsequent the zinc is removed via vacuum distillation and the recycled material obtained is in powder form. Finally the reapplication as a raw material for the production of new hard metals is provided. However, incorporated contaminations as well as coating materials remain in the recyclate. Based on a literature and patent survey, the selection of an appropriate solution for the removal of the hard coating took place. Empirical models were developed by a program for the generation and evaluation of model-based experimental designs. By considering the obtained results a selection of a suitable parameter-region for decoating of the examined cutting inserts is possible. An insight of the decoating-reaction is achieved besides the assignment. All obtained data constitute a promising issue for a pretreatment step of the zinc process for an improvement of the recyclate free of coating material.