... qualityNiobium is an associated metal of tantalum ,characterized in high strength ,high conductivity ,resistance to corrosion by liquid base metals ,section ... .00150.01 Table 2. Mechanical requirements (annealed condition) GradeTensile strength δbpsi (MPa), ≥ Yield strength δ0.2, psi (MPa),≥ Elongation in 1"/2" gage ...