The influence of spark plasma sintering temperatures on the microstructure, hardness, and elastic modulus of the nanocrystalline Al-xV alloys produced by high-energy ball milling

Al-xV alloys (x = 2 at.%, 5 at.%, 10 at.%) with nanocrystalline structure and high solid solubility of V were produced in powder form by high-energy ball milling (HEBM). The alloy powders were consolidated by spark plasma sintering (SPS) employing a wide range of temperatures ranging from 200 to 400 degrees C. The microstructure and solid solubility of V in Al were investigated using X-ray diffraction analysis, scanning electron microscope and transmission electron microscope. The microstructure was influenced by the SPS temperature and V content of the alloy. The alloys exhibited high solid solubility of V-six orders of magnitude higher than that in equilibrium state and grain size < 50 nm at all the SPS temperatures. The formation of Al3V intermetallic was detected at 400 degrees C. Formation of a V-lean phase and bimodal grain size was observed during SPS, which increased with the increase in SPS temperature. The hardness and elastic modulus, measured using nanoindentation, were significantly higher than commercial alloys. For example, Al-V alloy produced by SPS at 200 degrees C exhibited a hardness of 5.21 GPa along with elastic modulus of 96.21 GPa. The evolution of the microstructure and hardness with SPS temperatures has been discussed. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.