Titanium nitride (TiN) is a well-known coating material for the improvement of the tribological properties of tools and machine parts in industrial applications. The intention of this diploma thesis was the determination of the effect of an ion treatment by an Anode-Layer-Source ion gun on the adhesive strength of TiN coatings sputtered at room temperature. For a well adhering layer its sticking to the substrate surface is decisive. Different types of steel were used as substrates. By the contact angle measurement it was shown that the wettability of pretreated samples increases. During the investigations by means of the scratch test it was shown that with optimised pretreatment parameters of the Anode-Layer-Source ion gun the adhesion of the TiN layers was increased compared to opposite untreated samples. It was shown that with increasing chromium content of the substrates the adhesion was decreased.