| 摘要 |
A hot extrusion method for producing a metal piece comprising a tubular portion whereof one of the two ends is extended by a complex shape is provided. The method comprises: heating a billet from which the piece is made; and transferring the billet into a press extrusion tool, the tool including a cavity where the billet is placed and the shape of which substantially corresponds to the outer shape of the piece. The metal has, cold, a flow stress equal to or above 200 MPa. The complex shape and tubular portion are made by the following successive steps: at least one direct extrusion step using the first punch to produce the complex shape; a step for replacing the first punch with a second punch on the tool; at least one reverse extrusion step in the same tool to produce the tubular portion; and a step for evacuating the extruded piece. |
