AbstractThermal fatigue experiments on tungsten mock-ups have been carried out by an electron beam facility. Different designs of W monoblock mock-ups as well as a W macrobrush mock-up showed very good performance at maximum power densities between 14 and 20 MW/m2 (absorbed). For two plasma-sprayed tungsten mock-ups, failure limits were reached at 6.5 MW/m2. But from the test results, it can be concluded that these failure limits could be increased by improvement of the production methods. Vertical displacement event (VDE) simulation experiments followed by a thermal fatigue test were performed on a tungsten macrobrush mock-up. No indication of failure was observed from the macroscopic inspections or from the infrared images. But in the metallographic inspection, some cracks were observed at the interface between the tungsten teeth and the soft copper layer.