| 摘要 |
<p>PURPOSE:To produce a hollow shape material with one die by extruding >=2 pieces of partially fabricated Al extrudates, heating the joint surfaces thereof to an active state at a high temp. and fitting the fitting parts to each other. CONSTITUTION:A billet B is preheated to a prescribed temp. and is inserted into a container 4. The billet is then extruded forward by an extrusion stem 5 by which the two partially fabricated Al extrudates A1, A2 having the fitting parts to be fitted to the surfaces to be joined to each other are extruded from both extruding apertures 6, 7. The extrudates are so extruded that the temp. near the surfaces to be joined attains the prescribed temp. The joint surfaces of the extrudates A1, A2 right after the extrusion are positioned near to each other while the joint surfaces are maintained in the active state at the high temp. by the gaseous N2 blown to said surface. The joint surfaces are then fitted tightly to each other in such a manner that a tongue 13 fits tightly into a groove 17. Both extrudates A1, A2 are joined to each other and the shape material S is produced.</p> |
