炭素鋼の凝固過程における柱状オーステナイト粒の形成に及ぼす炭素濃度と冷却速度の影響
1990 年 76 巻 5 号 p. 714-721
詳細
1990 年 76 巻 5 号 p. 714-721
Steels containing 0.01 to 0.49 mass% carbon were melted and then cooled at rates of 0.3 to 40°C/s to investigate the condition favorable for the formation of columnar austenitic grains.
The results were summarized as folllows.
1) Large columnar grains were most remarkably developed in 0.1-0.3 mass%C region.
2) The region of the carbon content favorable for the development of columnar grains extended with increasing coiling rate.
The computer simulation of the cooling process of the ingots was carried out to investigate the formation mechanism of the coulmnar grains. From the experiment and the simulation, it was concluded that the formation of columnar austenitic grains was attributable to the steep temperature gradient at the δ→γtransformation front.
