The magnetic susceptibility of niobium

Abstract

The magnetic susceptibilities of several grades of niobium have been measured in the temperature range 78–400 K. For very-high-purity metal it is concluded that χ 300K = 214.1 ± 0.3 μ emu/mole. The susceptibility temperature dependence is not uniformly linear within 78–400 K but changes slope at 160 K, a temperature at which a change also seems to take place in the linear thermal expansion behavior. The susceptibility temperature dependences of high-purity niobium are: ∂χ ∂T (78–160 K) = −1.9 × 10 −2 μ emu/mole deg , and ∂χ ∂T (160–300 K) = −3.4 × 10 −2 μ emu/mole deg . Also considered are the influences of contamination by tantalum, and by oxygen.