WC-Co hard metals are widely used in wear-resistant parts, cutting tools, molds and mining parts, owing to the combination of high hardness and high toughness. WC-Co hard metals are usually produced by powder metallurgy, which makes it not possible to produce parts with complex geometries and often require post-processing such as machining. Additive manufacturing technologies offer a high level of design freedom, the integration of functional properties and the potential for cost and resource savings.  So far, however, WC-Co cannot yet be produced using laser-based additive manufacturing. [1,2,3,4] Therefore, various alloys from the W-C-Ti material system were investigated using a novel high-throughput-screening method in order to find an alternative binder system for WC-based hard metals to make them producible by laser-based additive manufacturing. In this screening method, powders are mixed in the desired compositions and compacted to obtain processable tablets. The surface of these tablets is then partially melted within the laser impact zone. The characterization of the produced samples is then carried out using microscopy, X-ray diffraction and Vickers hardness measurements. In this study, two screenings were carried out to analyze the influence of the carbon content and in addition of the tungsten-titanium ratio on the microstructure evaluation and hardness.

The investigated alloys show a two-phase structure of β(Ti,W) and δ(W,Ti)C1-x. By increasing the carbon content, an increase in the hardness values from 681 HV 0.5 to 1898 HV 0.5 was achieved due to the increasing phase fraction of δ. The variation of the tungsten-titanium ratio had no influence on the hardness. The hardness values achieved were in the range of 1900 HV 0.5 to 2100 HV 0.5. However, there were changes in the microstructures and phase fractions. Due to higher tungsten contents, the microstructures became finer and the phase fraction of δ was reduced.
After this study, the alloy with the most promising results was chosen for the production of additive manufactured model bodies.