Abstract: A mechanical part presents a main direction along which there extends a central zone forming a core and a peripheral zone forming a casing that surrounds the core. The core and the casing present a metallurgical bond between each other. The core is made of a first material presenting at least a metal matrix, and the casing is made of a second material presenting at least a metal matrix. The metal matrices of the first and second materials are based on the same metal, and at least one of the first and second materials is made of a metal matrix composite containing reinforcing elements dispersed in the metal matrix. The mechanical part can be used as a blade for a fan or a low pressure compressor.