OBTAINING A TITANIUM CARBOSILICIDE - BASED COMPOSITE AND STUDYING ITS ELECTROCONDUCTIVE PROPERTIES

Abstract

The issues on production of a new class of multifunctional composites by high-temperature self-propagating synthesis (SHS) of various metal powders are discussed. The class of such composites includes MAX phases. Their properties are studied. The results of the preliminary experiments show that a powder composite can be obtained from a mixture of titanium, aluminum, and carbon black powders by SHS, in which the maximum yield of the main MAX-phase Ti3AlC2 becomes 82,5%. According to the data of quantitative X-ray phase analysis (Powder Cell), by the SHS method of processing the sample FeSi + 3Ti + 2C (FeSi 30%), the amount of titanium carbide in the resulting product is 12,5%, since the synthesis of the released heat is not sufficiently large, and the final product does not have time to form completely. To bring the product to an equilibrium state, an additional annealing was carried out at a temperature of T =1250ºС (3 hours). Since titanium carbide is present in the final product, it is assumed that small additions of TiSi2 would increase the titanium carbosilicide content in the sintered composite due to the interaction of the carbide with titanium silicide. Therefore, annealing was also carried out at a temperature of T=1650ºС, but with the addition of 5 wt. % TiSi2. Annealing of the SHS product and the addition of 5% TiSi2 to the final product lead to an increase in the Ti3SiC2 content up to 100%, with a minimum amount of titanium carbide (traces). The obtained single-phase material based on titanium carbosilicide ensure the electrical conductivity of composite coatings at temperatures above 300°C. The microstructure of such a MAX material synthesized by powder metallurgy (SHS synthesis) methods, has a layered, laminate nature and can become a good raw material for further alloying of this compound with various metals for the development of powder metallurgy in Armenia.

The materials obtained on the basis of titanium carbosilicide at a temperature above 300⁰C ensure the electrical conduktivity of composite coatings.

The results of the experiment were confirmed by X-ray micro-analysis.