炭素鋼の歪時効硬化について

抄録

Strain age-hardening of carbon steel occurs in two stages during annealing after cold-working. The primary hardening at about 100°C takes place within the ferrite phase, and it may be reasonably explained by Cottrell’s mechanism, while the secondary in the range of 150∼340°C becomes marked with increase of the carbon content, and in addition, it is hardly accompanied by a rise of yield point upon measuring under a stress of the same kind and direction as those of prior working. It probably shows that the latter hardening is associated with the phase boundaries, since it is not so pronounced in the ferrite phase unlike in α solid-solution of brass, and that it is due, as in the case of α brass, to the removal of Bauschinger effect, which is more marked with the higher carbon steels. The secondary hardening in a given steel is, hence, chiefly affected by the arrangement, the shape and size of the cementite particles.