The pressure dependences of the eutectic or eutectoid temperatures in the systems CdPb, CdSn, PbSn and CdPbSn were investigated up to 2.5 GPa by improved differential thermal analysis at high pressure (HPDTA). The melting curves of cadmium, lead and tin were also determined up to 2.5 GPa. The experimental results of the pure metals and the three binary systems are consistent with results reported in the literature. The eutectic or eutectoid temperatures in the CdPb, CdSn, PbSn and CdPbSn systems increase smoothly with increasing pressure. However, in the PbSn and CdPbSn systems the simple eutectic relations disappear above a certain high pressure. The observed and calculated initial slopes ( dT dP at P = 0 ) for the pure metals and the eutectic mixtures are discussed on the basis of thermodynamics. The agreement is good.
