Electron microscope study of the systems cadmium-cadmium chloride and lead-lead chloride

The nature of the dispersed phase in the cadmium-cadmium chloride and lead-lead, chloride systems were investigated with the electron microscope. Preliminary experiments on preparing and examining the dispersed phase showed that it was most feasible to study the material by electron-microscopic examination of replicas made from the surfaces of the fractured materials. Melting apparatus and methods were chosen so that samples of the melts could be easily quenched to different temperatures and so that the samples could be easily fractured with a minimum of surface contamination. Of the conventional replicating techniques tried, that of carbon replicas pre-shadowed with chromium was found to be the most suitable. Electron micrographs of these surface replicas showed the presence of particles whose size varies over a large range. The larger particles are approximately spherical and may show partially developed facets, whereas many of the smaller particles depict an almost perfect hexagonal outline. The orientation of the particles appears to be related to the structure of the chloride samples --Abstract, page ii