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Its always hard to predict when brittle materials will break. But now a team
at the University of California at Santa Barbara has produced a laminated
ceramic with a predictable minimum strength (Science, vol 286, p 102).
Ceramics are strong and can withstand high temperatures, but their uncertain
failure points meant that they couldn鈥檛 be used in structural components. Fred
Lange鈥檚 group laminated alternate thick layers of aluminium oxide and thin
layers of aluminium silicate to create slabs that fail at consistent stress
levels. The thin layers, held under compressive strain, block the propagation of
the cracks that cause failure, Lange says.