A method preparing a metals carbides multilayer coating on at least one surface of a first carbon layer of a substrate, or under the surface inside the first carbon layer, by a reactive melt infiltration technique, includes: a) putting the surface into contact with a solid metal disilicide MSi2, M is selected from hafnium, titanium, and tantalum; b) heating the substrate and the metal disilicide to above the melting temperature of the metal disilicide; c) observing a plateau at the temperature for a sufficient duration so that the metal disilicide reacts with the carbon and forms a first multilayer coating including a dense and continuous layer of SiC, fully covered by a dense and continuous layer of MC; d) cooling the part with the first multilayer coating; and then, at the end of d), optionally e) depositing a second carbon layer at the surface of the first multilayer coating.