Research on Low Temperature Rolling Technology of Non-quenched Crankshaft S38MnSiV Steel
Author of the article:ZHU Ye
Author's Workplace：Technical Center,Shigang Jingcheng Equipment Development&Manufacturing Co.,Ltd.,Yingkou 115000,China
Key Words：low temperature rolling non quenched and tempered steel S38MnSiV grain size bands structure
Abstract：
Using 4100 t converter 120 t→120 t LF→120 t VD→Ф450 round billet continuous casting→slab heating→slab opening→eight continuous rolling(low temperature controlled rolling)to control cooling process’,150 mm in diameter crankshaft with S38MnSiV non-quenched and tempered steel was prepared.A comparative experiment was conducted between controlled rolling at low temperature and normal rolling.The results show that,compared with normal rolling,when the billet's soaking temperature is 1210-1260℃,the slab opening temperature is 1000-1050℃,the cooling rate after slab opening is controlled to 0.2-0.3℃/s,the rolling temperature is 880-895℃.When the cooling rate of S38MnSiV steel is controlled to 0.3~0.4℃/s,the grain size of 1/2R pearlite pellets of S38MnSiV steel is 6.5~5.0 grades,increasing by 2 grades.The heart level is 6.5〜4.0 grades,and the improvement is 3.5〜1.0 Grade 2.0 in banded structure,0.5 in increase;There is little difference in mechanical properties.
