PURPOSE: To obtain a composite material with less thickness deviation by adjusting partially the temperature of an outside-covering metallic material to adjust the thickness distribution of the covering material in manufacturing a composite material by extrusion coating a different kind of covering metal around a core material.
CONSTITUTION: In an extruder for extrusion coating a covering metal 2 around a core material 1 by inserting the core material 1 from a hollow mandrel 6 and applying an extrusion pressure on the covering metallic material 2 in the 8 direction by a ram 4 of a cylinder 5; heating or cooling units 14W16 are separately provided to respective surfaces 11W13 of a die holder 10. Next, on the way of extrusion, the distribution of the coating thickness of a composite material extruded from a die hole 9 is measured, to positively heat the surface 11 at the thinner thickness side of holder 10 by a medium 17 of the heating unit 14 or to positively cool the surface 13 at the opposite side by a medium 17 of the cooling unit 16, for instance. In this way, the thickness distribution of covering metal around the core material can be adjusted, and a composite material with less eccentricity is obtained.
YOSHIDA SHIGEAKI
KUDOU FUMITOSHI
| JPS5447856A | 1979-04-14 |
Next Patent: FORMATION OF ELECTRIC WELDED STEEL PIPE