POWER-DENSE THERMOELECTRIC MODULE. PHASE IV: SOLIDIFICATION OF THERMOELECTRIC MATERIALS UNDER THE INFLUENCE OF ULTRASONIC AGITATION.
Abstract
A technique is described for preparing fine-grained PbTe, PbTe-SnTe, Bi2Te3, Bi2Te3-Bi2Se3, and Bi2Te3-Sb2Te3 by ultrasonic agitation of a solidifying melt. Material prepared by this technique is dense and chemically homogeneous. The thermoelectric efficiency factors of ultrasonically prepared PbTe and PbTe-SnTe compare very favorably with that of material prepared by other techniques. The ultrasonically prepared Bi2Te3 and Bi2Te3 alloys normally possess lower thermoelectric-efficiency factors than material prepared by directional solidification. The lower thermoelectric efficiency of the (UA) material is associated with the anisotropic behavior of the electrical properties in Bi2Te3 layerlike structures. Comparison of compressive-flow curves for PbTe and SnTe-PbTe solid solutions prepared by various techniques shows that the ultrasonically prepared material has greatly superior ductility and strength. In the Bi2Te3 and Bi2Te3 alloy systems, the ultrasonic material shows higher compressive strengths than material prepared by directional solidification. The ductility of the Bi2Te3 and Bi2Te3 alloys prepared by ultrasonic agitation is essentially the same as that of material prepared by directional solidification. Preliminary results are reported on the Ge-Si solid solution system.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1964
- Accession Number
- AD0622393
Entities
People
- Martin Weinstein