Method for manufacturing an abradable layer

A process for manufacturing a substrate coated with an abradable layer, the substrate being a turbomachine part and the process comprising:

• forming the abradable layer on a separate substrate comprising a powder composition comprising at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], by heating said micrometric ceramic particles, as well as any nanometric ceramic particles that may be present, to a first temperature T1 greater than or equal to 600° C. and while the assembly is brought to the first temperature T1, increasing a compression pressure until it reaches, at a first time t1, a plateau at a value Pc which corresponds to the compression pressure to be applied during the sintering of the powder composition;
• then
• increasing the temperature of the powder composition and the separate substrate to the sintering temperature Tf reached at a second time t2;
• then
• maintaining the sintering temperature Tf and the compression pressure Pc until the third time t3 to obtain the abradable layer;
• and
• separating the abradable layer from the separate substrate;
• depositing the abradable layer thus formed on a surface of the substrate, and
• bonding the abradable layer thus deposited on the surface of the substrate wherein a temperature imposed during sintering, a sintering time and a compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.