ABSTRACT
In the pure form metals are often very soft, eg lead, aluminium and iron, so that most metals used in buildings are alloys containing controlled proportions of different metals. Adhesives, dealt with in, may be preferable where stress concentrations in thin sheet would be caused by mechanical fixings and where large areas are to be joined, without impairing the appearance of either part. Ferrous metals are discussed under the following headings: All ferrous metals contain carbon, derived originally from charcoal, and, since 1709, from the coke used in smelting the ore. Sandwich panels Stainless steel sheet on both sides of plywood or on light-weight cores of foamed plastics or honeycombed paper or foil. Pre-finished products such as plastics coated steel sheets can be cold formed since most coatings withstand more deformation than the base metal. Stainless steel and other alloys can be joined by ultrasonic vibrations when the parts are lightly clamped together.
