Investigation of structural, tribological and machining performances of tungsten carbide cutting tools with nickel binder produced by selective laser melting method

Today, rapidly advancing technology has increased the demand for technological products, particularly in aviation and other high-tech industries. Dynamic developments in technology and engineering have played an important role in the change of the machining industry, and have revealed the need for the development of internally contoured special cutting tools with better wear resistance and mechanical properties. The aim of this thesis is to investigate the feasibility of producing Tungsten Carbide (WC) tools with the desired design easily with the Selective Laser Melting (SLM) method, with the cheaper and easily obtainable Ni binder instead of the Co binder. In the study, optimum SLM production parameters were determined for WC powder material coated with Ni using the electroless deposition. Turning inserts were produced with the determined parameters and their structural, mechanical, tribological and turning properties were characterized. The optimum SLM production parameter set was determined as 100 W power, 600 mm/s scanning speed, 0° build orientation and 60% hatch spacing for 85 µm wall thickness determined under these conditions. Approximately 400 nm thick Ni layer was obtained with electroless Ni deposition. Since the obtained coating thickness was insufficient for bonding WC powders, Ni powder was added into the coated powder and in this way, the interaction between Ni coating and Ni powder was increased and bonding property was improved. By using optimum parameters, the parts with 98.8% relative density and 1962 HV0.3 microhardness value were produced. It was also observed that the turning performances of SLMed and conventional commercial inserts were quite close.