The experimental study of the Bi-Sn, Bi-Zn and Bi-Sn-Zn systems

• Author(s): Maria Helena Sousa Soares de Oliveira Braga ; J. Vizdal ; A. Kroupa ; Delfim Soares ; J. Ferreira ; Luís Filipe Malheiros de Freitas Ferreira
• Date: 2007
• Persistent ID: http://hdl.handle.net/10216/76141
• Origin: Repositório Aberto da Universidade do Porto
• Subject(s): Ciências Físicas; Física
• Document Type: Article
• Language: Portuguese

Description

The binary BiSn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersive solid state Spectrometry), DTA(Differential Thermal Analysis)/DSC (Differential Scanning Calorimetry) and RT-XRD (Room Temperature X-Ray Diffraction) in order to clarifydiscrepancies concerning the Bi reported solubility in (Sn). It was found that (Sn) dissolves approximately 10 wt% of Bi at the eutectic temperature.The experimental effort for the BiZn system was limited to the investigation of the discrepancies concerning the solubility limit of Zn in (Bi)and the solubility of Bi in (Zn). Results indicate that the solubility of both elements in the respective solid solution is approximately 0.3 wt% at200 C.Three different features were studied within the BiSnZn system. Although there are enough data to establish the liquid miscibility gapoccurring in the phase diagram of binary BiZn, no data could be found for the ternary. Samples belonging to the isopleths with w(Bi) 10%and w(Sn) 5%, 13% and 19% were measured by DTA/DSC. The aim was to characterize the miscibility gap in the liquid phase. Samplesbelonging to the isopleths with w(Sn) 40%, 58%, 77/81% and w(Zn) 12% were also measured by DTA/DSC to complement the study ofBiSnZn. Solubilities in the solid terminal solutions were determined by SEM/EDS. Samples were also analyzed by RT-XRD and HT-XRD(High Temperature X-Ray Diffraction) confirming the DTA/DSC results for solid state phase equilibria.