Prediction of density of stainless steel

Abstract

The change of the density of stainless steel with phase at temperature range from 773 K to 1973 K has been studied by a sessile drop profile method. Measurement of the density by a sessile drop profile method has to be carried out under heating conditions to avoid the influence both of undercooling and the shrinkage within the sample during solidification. Accuracy of experimental results was evaluated in comparison with previous studies for pure iron. The density of stainless steel was dependent on the phase but not chromium and nickel contents. Equations for prediction of the density in L, δ and γ phase regions were determined using the experimental results of ρL = -7.20×10-4 ΔTL+7.04; ρδ = 2.87×10-4 ΔTδ+7.27; ργ = 4.40×10-4 ΔTγ+7.43; 18 mass%≤Cr≤25 mass%, 4 mass%≤Ni≤25 mass%, 773 K≤T≤1973 K. The density of δ and γ coexisting phase (δ+γ) is then predicted from the following equation. ρ(δ+γ) = ρδ·fδ+ργ·fγ; 18 mass%≤Cr≤25 mass%, 4 mass%≤Ni≤25 mass%, 773 K≤T≤1973 K. These estimated values are in good agreement with experimental results.