Nitrogen as Alloying Element in Steel (15th Report). The Effect of Nitrogen on the Tempering of Coldworked Steels

Abstract

The present investigation has been carried out to ascertain the effect of nitrogen on the tempering of the coldworked steels. On steels containing various percentage of nitrogen, manganese, aluminium and titauium, the magnetical and electrical properties were measured under the condition of coldworking and tempering. From these investigation it has become clear that; (A) The changes at about 100°, 250° and 400∼550° begins to appear with the addition of nitrogen and become conspicuous as the nitrogen increases. (B) The relief of coldworking stress begins to appear at the temperature of about 300°. (C) The change at about 100° or 250° is due to the precipitation of nitrogen or carbon. (D) The change at about 400∼550° (or 650°) is due to resolution of nitrogen (or carbon). (E) The effect of nitrogen was reduced as manganese increases.