Accession Number : AD0678464

Title :   RHENIUM COATING OF REFRACTORY METALS BY THERMAL DISSOCIATION OF CHLORINE COMPOUNDS OF RHENIUM,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Zelikman,A. N. ; Baryshnikov,N. V.

Report Date : 21 DEC 1967

Pagination or Media Count : 11

Abstract : The analysis of thermodynamic data has shown that among the Re chlorides or oxychlorides only ReCl5 or ReOCl4 may be considered as suitable for the obtaining of the Re deposits by thermal dissociation. The ReCl5 was prepared by chlorination of Re powder at 500-600C and purification from oxychlorides distillation at 160-180C. The Re was deposited on Mo strips from ReCl5 carried by spectrally pure Ar. The quality of the coatings was examined metallographically and visually. In the 900-1250C temperature range, the degree of Re utilization increased with the temperature of the substrate. Above 1200C it remained constant being 60 and 53% for ReOC14 and ReCl5, respectively. ReOCl4 is more suitable for deposition of Re coatings since it is stable up to 600C, while ReCl5 dissociates into ReCl5 and Cl2 even at 190-200C, thus making impossible the achievement of high Re concentrations in the gas. Therefore, higher rates of deposition per unit area of substrate can be achieved with ReOCl4. Continuous deposition of Re on moving W filaments Heated electrically to 100-1200C was carried out from ReOCl4 and ReCl5 vapors. (Author)

Descriptors :   (*RHENIUM, METAL COATINGS), (*REFRACTORY METALS, METAL COATINGS), DISSOCIATION, RHENIUM COMPOUNDS, CHLORIDES, DEPOSITION, TUNGSTEN, MOLYBDENUM, USSR

Subject Categories : Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE