Investigation of possibility to fabricate Si3N4-TiN ceramic nanocomposite powder by azide SHS method

International Conference and Youth Scientific School on "Materials and Technologies of New Generations in Modern Materials Science"

Kondratieva, L.A.^1 ; Kerson, I.A.^1 ; Illarionov, A.Yu.^1 ; Amosov, A.P.^1 ; Bichurov, G.V.^1

Samara State Technical University, 244 Molodogvardeyskaya Street, Samara

443100, Russia^1

关键词: Ceramic nanocomposites;    Composite powders;    Halide salts;    Large amounts;    Nano-composite powders;    Nanostructured composites;    Self propagating high temperature synthesis;    Water washing;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/156/1/012032/pdf
DOI  :  10.1088/1757-899X/156/1/012032

来源: IOP

【 摘 要 】

The process of self-propagating high-temperature synthesis with use of a powder of sodium azide NaN3as a nitriding agent (the SHS-Az method) was applied to fabricate a nanocomposite powder Si3N4-TiN. Combustion of the initial mixtures of NaN3only with precursors that are halides of silicon and titanium: Na2SiF6, (NH4)2SiF6, Na2TiF6, (NH4)2TiF6did not allow us to synthesize the composite powder of Si3N4-TiN, as the phases of silicon nitride Si3N4were not formed. After water washing, the ultrafine powdered product of combustion consisted of one target phase of titanium nitride only and a large amount of impurity of side phases. Replacement of the halide salt of one of the elements (Si or Ti) by the powder of this element in the initial mixture of SHS-Az system resulted in formation of silicon nitride together with the titanium nitride and impurities. The least amount of impurities was obtained by burning the initial mixtures of xSi + y(NH4)2TiF6+ zNaN3system. Only the initial mixture of 9Si + (NH4)2TiF6+ 6NaN3allowed us to obtain as a result of the SHS-Az process the nanostructured composite powder of Si3N4-TiN without impurities.