Process for producing reinforced structural articles

摘要

Reinforced structural elements are produced by taking two or more sheets of the same or different malleable metal and applying a pattern of thermally decomposable stop-off material on an interfacial surface, solid phase green bonding the sheets one to another by squeezing them through squeezing rollers and sintering the sheets to improve the metallurgical bond therebetween.The composite can be formed into complex configurations having compound reentrant surfaces and then raised above a predetermined temperature to decompose the stop-off material to generate gas and inflate the sheets contiguous to the pattern.The stop-off material can be chosen to decompose essentially completely at a temperature above the predetermined temperature which facilitates forming prior to inflation or the material can include a portion which decomposes at the sintering temperature of the metallic sheets employed giving a two stage inflation. The stop-off material may be applied in many different patterns including continuous and non-continuous areas, areas in the form of alpha-numeric symbols or areas to provide both a decorative effect and a structural reinforcement. In another example the pattern may be applied on the interfacial surfaces of several sheets in the form of spaced parallel strips offset from one sheet to the next, to provide a honeycomb structure.