EQUILIBRIUM SILICIDES OF PALLADIUM.

The Pd-Si system was examined in the 13 to 25 at. % silicon range by X-ray diffraction, thermal analysis, and metallography. The compounds Pd//5Si. Pd//9Si//2, and Pd//3Si form peritectically. Pd//5Si is monoclinic, while Pd//9Si//2 and Pd//3Si are orthorhombic. These compounds form defect structures having low symmetry and large unit cells. Electron concentrations per unit cell govern formation. There was no evidence of either Pd//4Si or Pd//9Si//4.