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This work reports about preparation of W/Fe co-sputtered layers between tungsten and steel in order to ease their coefficient of thermal expansion mismatch.Iron and tungsten have been gradually co-sputtered on W tiles with real time deposition parameters changing to obtain a graded interlayer: SEM, EDS, XPS, HR-TEM have been used to characterize the W/Fe co-sputtered layer.W tiles co-sputtered with the W/Fe layers have been hot pressed to steel tiles: morphology and mechanical strength have been investigated for joints with and without W/Fe co-sputtered layer.Lap-shear tests in compression at room temperature have been made on hot pressed W/steel joints with and without W/Fe co-sputtered layer, showing a different behaviour.High flux test on joints with and without W/Fe co-sputtered layer are reported and discussed. The mechanical test results of manufactured joints are in good accordance with high heat flux test results, showing that the behaviour of hot-pressed joints with W/Fe co-sputtered layer was slightly worse if compared to joints without co-sputtered layer at the interface.

Tungsten-steel metal matrix composites are consolidated using electro-discharge sintering. At first steel and tungsten powders are sintered separately and then 25 vol% W, 50 vol% W and 75 vol% W mixed powders are sintered. A thorough process parametric study is carried out involving analysis of the influence of particle size distribution, sintering pressure, and discharge energy on the maximum discharge current and obtained residual porosity. Thermal expansion coefficient and the specific heat capacity of the optimized sintered composites are almost same as their theoretical values, however the thermal conductivities and the mechanical properties are lower than the expected values.