Protium and deuterium solubilities and diffusivities in Inconel 625 have been determined in the temperature range from 650 to 900 K and in the pressure range from 0.01 to 1 bar. The results can be described by where Ro = 8.314 J. mol−1 .K−1 , S in cm3 (NTP). cm−3, D in cm2.s−1, p in bar and T in K.