Study of Microstructural Defect Parameters in Vanadium–Aluminium Alloys using Warren–Averbach Method and Modified Rietveld Technique

Detailed X-ray diffraction line profile analysis using Warren–Averbach method and modified Rietveld technique has been performed on the X-ray diffraction profile of body centered cubic vanadium-base aluminium alloys of nominal compositions in wt % as V–26% Al (Alloy I), V–24% Al (Alloy II), V–20% Al (Alloy III) and V–18% Al (Alloy IV). The microstructural parameters such as coherent domain size, microstrain within the domains and compound faults were evaluated in the alloys by applying Fourier line shape analysis. The Fourier analysis has been done taking silicon as standard. The growth fault parameter (β) has been observed to be either negligibly small or negative. This shows that growth faults are absent in this bcc system. It has also been observed that the spacing fault (α ε ) is totally absent in the system because the values are negative. The faulting parameter (1.5 α+ β) and deformation stacking fault α obtained from these analyses are however, not negligible.