The study looked at how adding nickel (Ni) and copper (Cu) affects the properties of ultra-coarse grained cemented carbides. Ni and Cu help control the size and shape of the carbide grains, with Cu being better at stopping grain growth. Ni makes the grains stronger and tougher, improving wear resistance by 50%. On the other hand, Cu makes the carbides harder but less tough, leading to worse wear resistance. Overall, adding Ni is better for making strong cemented carbides for rock drilling, compared to Cu.