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1. A spectroscopic study was made of the reactions of several metals (Al, Cu, Ni, Co, Ti, Mo, W, and Kh18N9T steel) with silicon dioxide in the as-deposited condition and after annealing in the temperature range 600–1500°C. 2. In the contact reaction of SiO2 films with metallic surfaces up to the maximum temperatures of existence of these films, no individual metallic oxides or similar chemical compounds (such as olivines) are formed. 3. The temperature limits of stability of SiO2 films applied to various metallic substrates have been established. The most stable systems, remaining unchanged right up to 1450°C, are Mo-SiO2 and W-SiO2. 4. The reaction in metal-SiO2 film systems at temperatures below the film stability limits is limited to a polarizing action of the metallic substrate, which manifests itself in the appearance of additional absorption bands in the ranges 1320–1260 and 520–500 cm−1.

1. The method of electron beam vaporization of rods prepared from synthetic mullite can be successfully used for the deposition of vitreous aluminum silicate coatings with a composition close to that of mullite on metallic surfaces. 2. The method of infrared spectroscopy makes it possible to determine qualitatively the phase composition of such a coating, assess the degree of mullitization of deposited films, and detect in them any uncombined aluminum and silicon oxides. 3. The temperature ranges of compatibility of 0.35-μ thick aluminum silicate coatings with various metallic substrates have been determined. 4. The spectra of films deposited on the metals investigated show an extra band in the 1500-1400 cm−1 range, which is similar to the bands found in the spectra of silica and alumina films in the 1300-1260 and 1000-960cm−1 ranges, respectively.

The results of the study of the infrared spectra and electron-microscope investigations of mullite coatings obtained by plasma spraying allow us to consider as proved the possibility of obtaining these coatings of stoichiometric composition from mullite with the appropriate spraying cycles.