Making sandwich-type layer assemblies used e.g. in ship, aircraft and spacecraft building - using electro-resistance heating as well as laser heating as layers are forced together

摘要

Multi-layered elements are made up of top and bottom strips (11,12) and central hollow structure (15) in which a pulsed current is passed through the assembly to join it in contact points. The current is also used to monitor for non-fixed points in the assembly and as a result, controls the movement of laser beams to preheat the contact points. The current pulse is distributed over the width of the material strip and the short current pulse concentrates the current flux on the surface (11'). The rollers act to press the layers together. The surface of the strip is electrically heated pref. inductively, or laser heated. USE/ADVANTAGE - Producing sandwich-type hollow structures. Layers are directly and indirectly fixed together using electro-resistance and laser beam heating methods.