Equation to estimate the surface tensions of stainless steels

Surface tension (gamma) data for both austenitic and ferritic stainless steels have been analysed to derive an equation which will apply to the surface tensions of all stainless steels. It was assumed that the Al content was sufficient to hold the soluble oxygen content down to 5 ppm. The surface tensions of stainless steels can be expressed in terms of two variables, temperature and wt% sulphur: gamma(mNm(-1)) = 1840 -0.4(T - 1823) - 0.056TLn{1 + e 28798/T-8.5647 (0.68%S)} The calculated surface tensions were found to be within 3% of the measured values and values for the temperature dependence (d gamma/dT) values were similar to the measured data. (C) 2005 Springer Science + Business Media, Inc.