MECHANICAL-PROPERTIES OF EXTRUDED BI85SB15 ALLOY PREPARED BY MECHANICAL ALLOYING

The mechanical properties of the Bi85Sb15 thermoelectric alloy prepare d by mechanical alloying and consolidated by hot extrusion have been i nvestigated at 77 and 300 K. A three-point bending test was used in th e course of this analysis because the stress state of sample in bendin g is similar to the distribution of stresses in a thermocouple of a Pe ltier cooling device. The modulus of rupture of the polycrystalline sa mples is roughly the same at the two studied temperatures with a value of about 100 MPa. This value is about ten times that obtained for Bi8 5Sb15 Single crystals prepared by the Czochralski method.