制御圧延過程でのオーステナイトからフェライトへの変態温度の測定

抄録

For the purpose of measuring austenite-to-ferrite transformation temperatures in niobium-bearing steels during controlled rolling, various methods were investigated. The change in texture intensity as well as those in microstructure and strengths produced by deformation in the austenite-ferrite region was found to be useful for this purpose, those giving the same Ar₃ temperature.
Ar₃ temperature rises with the increase in the amount of deformation in non-recrystallization region. The increment is, however, much larger for a coarse austenite grain structure than for a fine one. Regardless of the difference in initial austenite grain sizes, Ar₃ temperature reaches the same value when the deformation in non-recrystallization region is increased to -70%. The rise in Ar₃ temperature is due to strain-induced transformation and grain fragmentation caused by deformation bands.