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 Table I shows the ultimate tensile strength and minimum permissible elongation for the most important materials used in locomotive construction.

Spring steel is not usually tested for tensile strength, but the springs are subjected to rapid deflection tests.

Bending Tests. Other tests specified include “cold bend” and “temper bend” tests. In the former, specimens cut from plates are doubled over cold, until the internal radius is not greater than the thickness of the plate, and the test piece must withstand this without fracture. The “temper bend” test is similar, but the piece is heated beforehand to a red heat and quenched