ELECTRICAL RESISITIVITY AND THERMAL CONDUCTIVITY OF ALLOYS OF THE TUNGSTEN-MOLYBDENUM SYSTEM.

Measurements are reported of the transport coefficients of Mo-86. 5 at. % W (from 1200 to 3000 K) and Mo-34. 4 at. % W alloys from 1200 to 2800 K. Results are also given for pure W (up to 3000 K) and Mo (up to 2600 K). The electrical resistivity was measured on wire specimens using a potentiometric technique in conjunction with a tubular furnace with a side hole for sighting a pyrometer. Thermal conductivity was measured under the conditions of exponential temperature distribution in a wire specimen heated by electric current. The exponential factor was measured with the aid of a differential plot by using the ratio between the voltage drops along two portions of the sample. The error in the electrical resistivity data is similar 1% and in the thermal conductivity data less than 5%. The results are used to derive the composition dependence of the electrical resistivity and of the Lorenz number.