Research on the influence of fabrication methods on the performance of fusion reactor divertors

• The ability of the divertor to remove 20 MW/m 2 for 1000 cycles has been verified. • The influences of different fabrication methods on the performance of the divertors are investigated. • HHF tests results indicate divertor fabricate by “‘casting + HIP’+EW + VB” performs better than “‘casting + HIP’+EW + HIP”. • The fabrication method “‘casting + HIP’+EW + VB” is very promising for use in the divertors for other fusion devices or reactors. The divertor is a critical plasma-facing component in fusion reactors, presenting significant challenges in design and manufacturing. Utilizing a sandwich-like layered structure, the flat-type divertor requires distinct fabrication methods for interlayer bonding due to the varying welding properties of its constituent materials. The bonding quality at each interface is paramount, directly determining the component’s operational performance and lifespan. Thus, achieving reliable bonding under operating conditions is a stringent requirement. While current studies highlight the impact of fabrication methods on performance, direct comparative evaluation remains difficult due to inconsistencies in materials, structures, and test parameters across existing literature. To address this, this work reports the evaluation results on two divertor mock-ups. These mock-ups are differentiated solely by the bonding method applied at the interface between the intermediate interlayer (copper, Cu) and the heat sink material (oxide dispersion strengthened copper, ODS-Cu). Specifically, the first mock-up was fabricated using Hot Isostatic Pressing (HIPping), whereas the second mock-up was bonded via brazing. Then, the effects of these two methods on heat transfer, thermal fatigue resistance and overall reliability were systematically investigated through high heat flux test.