Authors:
Srinivasan Suresh (1), Gillham Joe (1), Marshall M. Jessica (1)
1- University of Warwick, Coventry, United Kingdom
Abstract:
First wall (FW) materials for future fusion reactors have tungsten (W) and ferritic/martensitic steel (FMS) as prime materials. The significant difference in thermo-physical properties of W-FMS joints, specifically, high ductile-brittle transition temperature (DBTT) in W making it brittle at low temperatures and embrittlement due to recrystallization. Cemented tungsten carbide (cWC)-reactive sintered boride (RSB) composites are considered as promising candidate to develop reliable joining technology albeit cWC-RSB to steel joint is challenging. Brazing is a prospective technology; brazing experiments were conducted using Cu-based and FeCr-based interlayers/foils with low-activation elements and high Z-materials. This study compares the effect of brazing compositions, temperature and holding time. The microstructures, mechanical properties, and the strength of brazed joints were investigated using SEM, EDS and EBSD analysis with microhardness and fracture toughness. The results show that cWC-RSB to steel successfully joined by brazing, achieved like W-steel joints and boron in cWC-RSB suppresses the thermo-physical property mismatch.
DOI:
https://doi.org/10.59499/EP246283792
