The application relates to a preparation process of a
copper wire and belongs to the technical field of wire production, which comprises the following steps: S1, preparing an
oxygen-free
copper rod by using an up-drawing method; S2, performing
surface cleaning on the
oxygen-free
copper rod; and S3,
processing the
oxygen-free copper rod after the
surface cleaning into a copper flat wire through a continuous extruding
machine; wherein the continuous extruding
machine comprises a forming cavity and an extruding die which is detachably fixed in the forming cavity, the extruding die is integrally formed with a die
mouth structure, the die
mouth structure comprises a gradually-changing forming section and an equal-section shaping section, the geometric profile of the gradually-changing forming section is formed by
lofting a circular cross section at an inlet end along an axial direction to a target rectangular cross section at an outlet end, the equal-section shaping section is connected with the outlet end of the gradually-changing forming section, and the cross section shape of the equal-section shaping section is consistent with the target rectangular shape. The application can inhibit edge skinning and cracks, avoid sudden change of pressure on the die during
extrusion, thereby prolonging the service life of the die, and without deliberately slowing down the production speed to relieve the pressure, the efficient production requirement of the
copper wire is ensured.