The compatibility of lead and tin telluride with metals

Abstract

For the design of efficient joining methods and the evaluation of the long term stability of thermoelectric junctions, a basic knowledge of the appropriate phase equilibria is desirable. The chemical reaction behavior of lead- and tin-telluride with a number of metals was therefore surveyed.

Guertle's “Klar-Kreuz” method has been used to establish the direction of the reactions: $\text{x}\text{PbTe}\text{+ y}\text{M}\text{↔}\text{M}{}_{\mathrm{y}}\text{Te}{}_{\mathrm{x}}\text{+ x}\text{Pb}$ or the corresponding reactions with SnTe.

For the metals investigated with PbTe it was found, that in the case of Ti, V, Cr, Mn, Zn, Ga, Zr, Nb, Cd, In and Ta the reaction goes from left to right. For Fe and W it proceeds from right to left. In the cases of Ni, Cu, Ag and Mo the equilibria are more complex and cannot be described by the cited equation. Reactions of SnTe with metals were quite similar. Again, Mn, Zn, Cd and Ta were found to react from left to right, Fe and W from right to left. Here, too, Ni, Cu, Ag and Mo followed more complex equilibria.