Accession Number:

ADA218946

Title:

Improvement Study of Iron Disilicide Thermoelectric Materials

Descriptive Note:

Final technical rept. Sep 1989-Jan 1990

Corporate Author:

TUNZINI NESSI ENTREPRISE EQUIPEMENT RUEIL-MALMAISON (FRANCE)

Report Date:

1990-01-12

Pagination or Media Count:

17.0

Abstract:

In many applications at high temperature, the semiconducting compound beta - Fe Si2 has been already proposed for power generation. The goal of this part of the study is to obtain pure semiconducting beta - Fe Si2 phase as a material of reference for thermoelectric properties. The melting of elemental Iron and Silicon powders is done at 1250 C and the transition of the metallic alpha to semiconducting beta phase is obtained by annealing. This classical preparation of beta - Fe Si2 was time consuming and because of the phase diagram results in the production of inhomogeneous alloys. Mechanical alloying was considered as an alternate method of producing beta - Fe Si2. This method for elaborating the compound from lower temperature must avoid the difficulties of sublimation and evaporation of the components. It also allows the optimization of beta - Fe Si2. The results of the two elaborating methods are compared by x ray diffraction measurements. These results on beta - Fe Si2 obtained by mechanical alloying, were original. This process now appears to be a reliable method to introduce amounts of dopant in the material. It must now be developed.

Subject Categories:

  • Fabrication Metallurgy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE