THE THERMAL-CONDUCTIVITY OF AISI 304L STAINLESS-STEEL

A compilation and critical analysis of the thermal conductivity (lambda) of AISI 304 stainless steel (SS) between 100 and 1707 K has been given in the literature. The author represented his "recommended" values of lambda by an inflection in the lambda versus temperature relationship between 300 and 500 K. Because a physical mechanism had not been identified that would produce such a temperature dependence in lambda of 304 SS, interest was generated in the possible existence of an as yet undiscovered phenomenon that might cause such an inflection. Consequently, experimental verification of the inflection was sought. The present paper presents recent measurements of lambda, the electrical resistivity, and the absolute Seebeck coefficient of 304L SS from 300 to 1000 K and of the thermal diffusivity (alpha) from 297 to 423 K. The lambda values computed from the alpha measurements were within +/- 1.6% of the directly measured lambda. An inflection was not observed in the temperature dependence of lambda between 300 and 500 K. After careful evaluation and because a physical mechanism still has not been identified which would produce such an inflection, the authors conclude that the inflection in the lambda vs T relationship reported in the literature was caused by the data analysis technique.