AbstractThe saturation solubilities of nickel and manganese in Pb17Li have been measured over the temperature range of interest for the use of Pb17Li as a coolant and tritium breeder in fusion reactors. Nickel was found to have a particularly high solubility in Pb17Li as given by the equation: Log10S(wppm) = 4.832−981.2/T(K) for T = 520−728 K. The solubility of nickel in pure lead was also determined and found to be in good agreement with literature data. The solubility of manganese was found to be much lower than that of nickel in Pb17Li and is given by the equation: Log10s(wppm) = 6.732−2938/T(k) for T = 531−783 K. The solubility of chronium was found to be very low and the data subject to too much scatter to be fitted to a sensible equation. The possibility of interference by oxygen dissolved in the Pb17Li is discussed. Equilibration measurements of the dissolution of Ni, Cr, Mn and Fe from Type 316 stainless steel are also described.