Microstructure and Compression Properties of V(SS)-V(3)B(2) Eutectic Alloys in the V-Si-B System

The present study reports on the microstructural evolution and room temperature plasticity of V(-Si)-B alloys with respect to the V solid solution (V(SS))-V(3)B(2) phase region. To investigate the occurring effects systematically, different binary V-B and ternary V-Si-B alloys were produced by conventional arc melting. Scanning electron microscope (SEM) analyses and X-ray diffraction (XRD) measurements were used to characterize the resulting as-cast microstructures. For the first time, the eutectic composition was systematically traced from the binary V-B domain to the ternary V-Si-B system. The observations discover that the binary eutectic trough (V(SS)-V(3)B(2)) seems to reach into the ternary system up to an alloy composition of V-5Si-9B. Room temperature compression tests were carried out in order to study the impact of single-phase and multi-phase microstructures on the strength and plasticity of binary and ternary alloys. The results indicate that the V(SS) phase controls the plastic deformability in the V(SS)-V(3)B(2) eutectic microstructure whereas the intermetallic V(3)B(2) acts as a strong hardening phase.