Lattice parameters and thermal expansion of the T2-phase of the Nb–Si–B system investigated by high-temperature X-ray diffraction

摘要: Abstract The lattice parameters and thermal expansion coefficients ( α a c ) of the T 2 -phase Nb–Si–B system with different boron contents were determined from high temperature X-ray diffraction data (298–1473 K). Alloys nominal compositions Nb 62.5 Si 37.5 , 64 30 B 6 14.4 21.6 (at.%) prepared high-purity materials through arc melting heat-treatment under vacuum. Both decrease increasing content. A significant in is observed content while remains practically unchanged, diminishing anisotropy ratio / approximately 1.2 at binary composition to 0.7 .