The Zr-rich zone in the Zr-Pt system

The phase diagram for the platinum-zirconium system presented in 1961 by Kendall and co-workers has been considered as the fundamental work for ulterior works and assessments. The main features postulated in the region between 0-50 at.% Pt were the existence of the solid solutions alpha Zr (hcp) and beta Zr (bcc), and the two intermetallic compounds Zr sub 2 Pt and ZrPt. Later reports of other authors have mentioned the existence of other intermetallic compounds in the platinum-rich region. In the zirconium-rich region the presence of Zr sub 5 Pt sub 3 instead of Zr sub 2 Pt, and the presence of Zr sub 3 Pt were proposed. Other contributions added further knowledge about melting temperatures and range of occurrence of the various phases involved in the binary diagram. In the latest revisions of zirconium-platinum phase diagram the major modification to the proposal mentioned above was the consideration of the Zr sub 5 Pt sub 3 intermetallic compound instead of Zr sub 2 Pt. In the present work, an experimental study of the zirconium-rich corner of the phase diagram was accomplished and several modifications are suggested.