A method for preparing a metals carbides multilayer coating on at least one surface of a first carbon layer of a substrate, and optionally under said surface inside said first carbon layer, by a reactive melt infiltration technique, wherein the following successive steps a) to d) are carried out: a) the surface is put into contact with a solid metal disilicide MSi 2 wherein M is selected among hafnium, titanium and tantalum; b) the substrate and the metal disilicide are heated up to a temperature T P above the melting temperature of the metal disilicide; c) a plateau at the temperature T P is observed for a sufficient duration so that the metal disilicide reacts with the carbon and forms a first multilayer coating comprising a dense and continuous layer consisting of SiC, fully covered by a dense and continuous layer consisting of MC; d) the part provided with the first multilayer coating is cooled; and then, at the end of step d), optionally the following step e) is further carried out: e) a second carbon layer is deposited at the surface of the first multilayer coating; at the end of step d) or of step e), the following successive steps f) to i) are further carried out: f) the surface of the first multilayer coating still containing carbon or the surface of the second carbon layer is put into contact with a solid metaldisilicide MSi 2 wherein M is selected among hafnium, titanium, and tantalum; g) the surface of the first multilayer coating still containing carbon and the metal disilicide, or the second carbon layer and the metal disilicide are heated up to a temperature T P above the melting temperature of the metal disilicide; h) a plateau at the temperature T P is observed for a sufficient duration so that the metal disilicide reacts with the carbon and forms a second multilayer coating comprising a dense and continuous layer consisting of SiC, fully covered by a dense and continuous layer consisting of MC; i) the part provided with the second multilayer coating is cooled; and then, at the end of step i), optionally the following step j) is further carried out: j) a third carbon layer is deposited at the surface of the second multilayer coating; and at the end of step i) or of step j), optionally the following step k) is further carried out: k) silicidation of the surface of the second multilayer coating still containing carbon or of the third carbon layer is carried out, with liquid Si, whereby a SiC layer is obtained on the second multilayer coating. a) the surface is put into contact with a solid metal disilicide MSi 2 wherein M is selected among hafnium, titanium and tantalum; b) the substrate and the metal disilicide are heated up to a temperature T P above the melting temperature of the metal disilicide; c) a plateau at the temperature T P is observed for a sufficient duration so that the metal disilicide reacts with the carbon and forms a first multilayer coating comprising a dense and continuous layer consisting of SiC, fully covered by a dense and continuous layer consisting of MC; d) the part provided with the first multilayer coating is cooled; e) a second carbon layer is deposited at the surface of the first multilayer coating; f) the surface of the first multilayer coating still containing carbon or the surface of the second carbon layer is put into contact with a solid metaldisilicide MSi 2 wherein M is selected among hafnium, titanium, and tantalum; g) the surface of the first multilayer coating still containing carbon and the metal disilicide, or the second carbon layer and the metal disilicide are heated up to a temperature T P above the melting temperature of the metal disilicide; h) a plateau at the temperature T P is observed for a sufficient duration so that the metal disilicide reacts with the carbon and forms a second multilayer coating comprising a dense and continuous layer consisting of SiC, fully covered by a dense and continuous layer consisting of MC; i) the part provided with the second multilayer coating is cooled; j) a third carbon layer is deposited at the surface of the second multilayer coating; k) silicidation of the surface of the second multilayer coating still containing carbon or of the third carbon layer is carried out, with liquid Si, whereby a SiC layer is obtained on the second multilayer coating.