高炭素帯鋼の硬度組織に及ほす焼鈍の影響 (II)
冷間加工後の高炭素帯鋼について
1954 年 40 巻 8 号 p. 761-765
詳細
1954 年 40 巻 8 号 p. 761-765
Typical four samples among those samples which had been reported by Report I (Tetsu to Hagtime No. 7, July 1954 p. 675-680), were annealed and cold-rolled in several degrees of reduction. The effect of annealing temperature and the rolling reduction on their hardness and structure was studied. The results were as follows:
1) The relation between the rolling reduction and the recrystallization temperature was such that the temperature was lowered as the rolling reduction increased.
2) The relation between the rolling reduction, and the hardness value was lowered as the rolling reduction decreased except at around a temperature of the recrystallization.
3) The relation between the rolling reduction and the spheroidizing of carbide after annealing was such that the spheroidizing of carbide became slightly perfect and uniform as the rolling reduction increasd.
4) The effect of the rate of cooling from above the transformation temperature on the hardness was revealed in that the hardness was lower in the slow cooling than in air cooling.
In conclusion, the annealing condition of the hot-rolled high-carbon steel strips must be chosen within a narrow temperature range. In the case of a process-annealing of the cold-rolled steel strip, the structure and the hardness obtained were found uniform even if the temperature range had been chosen rather wide.
