Strength of Light‐Alloy Components Available to Purchase

A FEATURE of many of the light alloys now in common use is that the stress and strain curve often does not evidence any well defined region in which the elastic strain becomes plastic strain, and a linear portion of the diagram from the origin, which in the case of so many metals represents a region of proportionality, is sometimes almost non‐existent, the diagram being curved right from the origin so that it is not possible to define any region or limit of proportionality, and the proof stress; by standard definition, has accordingly a relatively low value compared with the ultimate tensile stress of the alloy concerned. (Fig. 1).