中炭素低合金鋼の変態挙動に及ぼす引張応力付加の効果

抄録

In order to accelerate the ferrite-pearlite transformation of medium carbon low alloy steel bars, the possibility of controlling the transformation behavior by application of the tensile stress during cooling after rolling was investigated. Tensile stress was applied by controlling the strain rate considering the stress drop due to relaxation. It was found that acceleration of ferrite transformation was occured by developed method. This results proved this method to be effective for softening the rolled bars. Furthermore, increase of uniform elongation up to about 60% occured in the case of straining during transformation. Discussion was focussed on the role of the applied stress and it was concluded that applied stress increased the internal stress of the austenite and resulted in the increased nucleation rate of ferrite transformation.