Abstract: A steel alloy contains in weight-% 0.5-1.0 C, 1-2 Si, max 0.2 Mn, preferably max 0.001 S, 0.1-0.5 Cr, balance essentially only iron. In the form of a cold rolled, hardened and tempered strip it can be used as a backing material for band saw blades, frame saw blades and circular saw blades, where the teeth are tipped with a different material than the backing material. This steel strip has a structure consisting of tempered martensite, and possibly remaining carbides, obtainable by hardening from a temperature between 780.degree. and 1000.degree. C. and tempering at a temperature between 200.degree. and 550.degree. C.

Abstract: A machine to deform the gullets of saw blades, thereby increasing the resistance of the saw blade to fatigue cracks, by compressing the gullet bottom, the compression being accomplished by pressing the saw blade between one fixed die and one which is pressed upon by a threaded member, said member being turned a part of a turn, thereby moving axially, by being attached to a lever arm, which is lifted and pressed down by a piston, and comprising a mechanism for advancing the saw blade one tooth pitch after each compressing cycle.