Abstract: In a method of manufacturing parts or powders made of a compound of silicon or of a metal by exothermally reacting parts or powders of silicon or a metal in the solid state with a gas, wherein the differential flow rate or the pressure variation of the reactive gas in contact with the part or the powder is sensed, and the reaction is performed at increasing temperatures as a function of the said differential flow rate or pressure of the reactive gas:the improvement wherein a maximum differential flow rate or a maximum speed of pressure drop of the reactive gas is predetermined as a function of the chemical nature of the parts or powders, and optionally as a function of the density and the size of the parts, and the rise in temperature is suspended when the differential flow rate or the speed of pressure drop of the reactive gas reaches the predetermined maximum value, beyond which the reaction would run away and prevent complete transformation of the parts or the powders being obtained.

Abstract: A method of manufacturing a dense silicon carbide ceramic includes heat treating an alpha silicon powder in a vacuum to between 1200.degree. and 1400.degree. C., adding a boron powder either before or after heat treating, then, adding a substance containing carbon, milling the mixture, compressing the milled mixture into a desired shape, sintering the formed shape at 2100.degree. C. in an argon atmosphere. The method has particular application to manufacturing parts for gas turbines.