| 摘要 |
PURPOSE:To prevent the breakage of a core at the time of starting extrusion by joining a wire material having high tensile strength to a core wire to use it as the core wire in a specific range at the time of starting its extrusion in manufacturing a composite metallic wire by extrusion. CONSTITUTION:An aluminum 4 is coated on the circumference of a core wire 8 having low tensile strength such as a mild steel one, and a composite metallic wire is manufactured as an aluminum coated steel wire 6 by extruding it through a die 5 of a fixed shoe block 2. At that time, the wire is often broken at the time of starting its extrusion because of large static friction between the coating material Al of the surface and the core wire 8 made of mild steel, etc. In this case, a wire 7 having high tensile strength such as a hard steel wire or music wire is welded 9 to the mild steel core wire 8 before extruding it. The wire 7 is strong enough for a drawing force at the starting time of extrusion, and not to break; as the static friction transfers to a dynamic one thereafter, a composite metallic wire is continuously extruded without causing a breakage of core wire, even if it has low tensile strength such as a mild steel one. |
