W–Cu/Cu composite electrodes fabricated via laser surface alloying

It is a long-term requirement to reduce the arc ablation rate and the W content of W–Cu composites. In this work, laser surface alloying was employed to prepare a novel W–Cu/Cu composite that contained a high W content on the surface but a low W content for the whole composite. The new W–Cu electrode exhibited a lower arc ablation rate than the commercial one. The underlying mechanism was attributed to the higher thermal conductivity of the new W–Cu/Cu composite with the low W consumption as a whole. This study opens a door to overcome the trade-off of the ablation resistance and W consumption of the W–Cu electrodes.