Abstract
Solubility of sulfur in Fe–V and Fe–Nb alloys was experimentally determined using a diffusion couple technique. Solubility product of VS and NbS in ferrite (α) and austenite (γ) phases were determined as log(mass%V)(mass%S)α=4.76−10100/T, log(mass%V)(mass%S)γ=4.90−11000/T and log(mass%Nb)(mass%S)γ=4.70−10500/T in the temperature range from 1523 to 1573 K. A thermodynamic analysis was also carried out to evaluate the formation energy of VS and NbS. The estimated formation energy of VS and NbS are ΔGVSsulfide=−263100+61.0T (J/mol) and ΔGNbSsulfide=−260800+68.4T (J/mol), respectively.
