Ancient and modem laminated composites - from the Great Pyramid of Gizeh to Y2K

Laminated metal composites (LMC's) have been cited in antiquity; for exampl e, an iron laminate that may date as far back as 2750 BC was found in the G reat Pyramid in Gizeh in1837. A laminated shield containing bronze, tin, an d gold layers is described in detail by Horner. Well-known examples of stee l laminates. such as an Adze blade, dating to 400 BC can be found in the li terature. The Japanese sword is a laminated composite at several different levels and Merovingian blades were composed of laminated steels. Other exam ples are also available, including composites from China, Thailand, Indones ia, Germany, Britain, Belgium, France, and Persia. The concept of laminatio n to provide improved properties has also found expression in modem materia ls. Of particular interest is the development of laminates including high-c arbon and low-carbon layers. These materials have unusual properties that a re of engineering interest: they an similar to ancient welded Damascus stee ls. The manufacture of collectable knives, labeled "welded Damascus," has a lso been a focus of contemporary knife makers. Additionally, in the former Soviet Union, laminated composite designs have been used in engineering app lications. Each of the above areas will be briefly reviewed, and some of th e metallurgical principles will be described that underlie improvement in p roperties by lamination. Where appropriate, links are made between these pr operty improvements and those that may have been present in ancient artifac ts. (C) 2001 Elsevier Science Inc. All rights reserved.