A method of assembly between a work piece made of a metal material and a work piece made of an organic-matrix composite material, comprising the following successive steps: a) a step of providing said two work pieces (1, 2), wherein said work pieces (1, 2) each include a surface (11, 21) intended to be welded to a complementary surface (11, 21) of the other work piece (1, 2), and characterized in that: said surface to be welded of said composite work piece is consisted, at least partially, by an exposed area of at least one metal insert that is partially embedded into said composite work piece, and characterized by the following steps: b) a step of positioning said surfaces to be welded (11, 21) opposite to each other and remote from each other, and c) a step of throwing at high speed the surface to be welded of the metal work piece and/or of the exposed area of the metal insert, against one another, to obtain high-speed pressing of said surfaces to be welded (11, 21) against each other and to obtain a weld between the exposed area of the metal insert of the composite work piece and the complementary area of the surface to be welded of the metal work piece, the throwing step is implemented so as to obtain a progressive pressing of the surfaces to be welded (11, 21) against each other, to ensure an expulsion of the oxides, and the metal work piece and/or the exposed portion of the metal insert includes a portion to be thrown (15, 51), a front surface (151, 53) of which constitutes the surface to be welded (11, 21), and said progressive pressing is obtained through: - at least one electrically insulating shim provided between the two work pieces (1, 2) and surrounding the portion to be thrown, or - a boss-shaped portion to be thrown, or - a fold at the edge of the metal work piece, intended to form said portion to be thrown. a) a step of providing said two work pieces (1, 2), said surface to be welded of said composite work piece is consisted, at least partially, by an exposed area of at least one metal insert that is partially embedded into said composite work piece, and characterized by the following steps: b) a step of positioning said surfaces to be welded (11, 21) opposite to each other and remote from each other, and c) a step of throwing at high speed the surface to be welded of the metal work piece and/or of the exposed area of the metal insert, against one another, to obtain high-speed pressing of said surfaces to be welded (11, 21) against each other and to obtain a weld between the exposed area of the metal insert of the composite work piece and the complementary area of the surface to be welded of the metal work piece, the throwing step is implemented so as to obtain a progressive pressing of the surfaces to be welded (11, 21) against each other, to ensure an expulsion of the oxides, b) a step of positioning said surfaces to be welded (11, 21) opposite to each other and remote from each other, and c) a step of throwing at high speed the surface to be welded of the metal work piece and/or of the exposed area of the metal insert, against one another, to obtain high-speed pressing of said surfaces to be welded (11, 21) against each other and to obtain a weld between the exposed area of the metal insert of the composite work piece and the complementary area of the surface to be welded of the metal work piece, the throwing step is implemented so as to obtain a progressive pressing of the surfaces to be welded (11, 21) against each other, to ensure an expulsion of the oxides, and the metal work piece and/or the exposed portion of the metal insert includes a portion to be thrown (15, 51), a front surface (151, 53) of which constitutes the surface to be welded (11, 21), and said progressive pressing is obtained through: - at least one electrically insulating shim provided between the two work pieces (1, 2) and surrounding the portion to be thrown, or - a boss-shaped portion to be thrown, or - a fold at the edge of the metal work piece, intended to form said portion to be thrown. - at least one electrically insulating shim provided between the two work pieces (1, 2) and surrounding the portion to be thrown, or - a boss-shaped portion to be thrown, or - a fold at the edge of the metal work piece, intended to form said portion to be thrown.