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Tungsten and vanadium (W-V) alloys (with 1, 5 and 10 wt.% V) are fabricated by hot pressing (HP) at 1800C under 20 MPa for 2 h. The effects of V content on the microstructures and mechanical properties of W-V alloy are investigated. The results indicate that with increasing V content, (i) the formation of W-V alloying phase is enhanced and the grain size of W-matrix is significantly refined; (ii) the relative density gradually increases from 92.16% to 97.72% in the case of pure W to W-10 wt.% V; (iii) the hardness rises linearly while the bending strength decreases, which is related to the enhanced alloy phase formation. [ABSTRACT FROM AUTHOR]

Tungsten based vanadium alloys have been fabricated by powder metallurgy and consolidated by spark plasma sintering (SPS) at temperature of 1600 °C for 3–5 min at 50 MPa. Four different concentrations of vanadium ranging from 1 to 10 wt.% were used to investigate the behavior of the developed alloys. X-ray diffraction analyses were performed for all four compositions of tungsten vanadium alloys. The morphology of cross sectional crack surfaces of sintered alloys was analyzed by scanning electron microscopy. The variations of vanadium concentration has not only shown an obvious impact on the microstructures, but also improved the densification and mechanical properties of the tungsten based materials. The maximum relative density of 98.5% was achieved for the highest concentration (10 wt.%) of vanadium alloy with micro hardness of 507 HV and good bending strength of 692.5 MPa. [ABSTRACT FROM AUTHOR]

The thermal stability is important for tungsten based alloys as plasma facing materials to survive against high heat flux in fusion reactors. In this work, the thermal stability of W-5%V alloy fabricated following a powder metallurgy route by spark plasma sintering technique has been studied. To investigate the impact of temperature on the mechanical properties and microstructures, the alloy was subjected to heat treatment for 2 h over the temperature range 900-1500°C in a pure argon furnace. The micro-hardness values of the heat treated alloys were highly stable as compared to pure tungsten. A slight decrease flexural strength was observed with increasing annealing temperature. The maximum change flexural strength at the highest treated temperature was noted about 14% lower. The morphology analyses of the crack surfaces by scanning electron microscopy did not identify a drastic change in tungsten grain size, after heat treatment. The results indicate that the addition of vanadium in tungsten improves the overall thermal stability of microstructures and mechanical properties. [ABSTRACT FROM AUTHOR]