Fabrication, microstructure, and properties of W–Re/graphite composites

The W‒Re/graphite composites were sintered by vacuum hot-pressing sintering at 1850 ℃ and 30 MPa, using the W–Re plates and the graphite blocks as the raw materials and the Mo/Zr mixed powders as the solder. The microstructure, shear fracture, and shear properties at room temperature of the W‒Re/graphite composites were investigated. The results show that, the obvious delamination occurs in the Mo/Zr welding layer of the hot pressing sintered composites. The phase composition in the graphite-adjacent area is ZrC and Mo₂Zr, and the phase composition in the W–Re-adjacent area is Mo₂Zr and zirconium-based solid solution (Zrss). The fracture of the composites mainly occurs at the interface between the solder and the graphite, the solder does not penetrate into the graphite obviously to form a pinning effect, and the shear strength of the composites at room temperature is about 5 MPa.