摘要
利用光学显微镜、扫描电镜等分析了不同热轧工艺下420 MPa级薄带钢组织、性能和氧化铁皮的演变。结果发现,不同冷却速度是造成带钢组织性能差异的主要原因,在低温轧制、快冷工艺下,带钢边部表现出中温转变特点,横向组织差异明显,带钢屈服强度为458 MPa,伸长率为26.46%;在高温轧制、缓冷模式下,横向组织均匀性得到改善,屈服强度降低25 MPa,伸长率增加2.50%;低温轧制、快速冷却的工艺路线抑制Fe_(3)O_(4)的高温氧化,带钢中部氧化铁皮厚度比轧制温度高和冷却速率低的轧制小1.13μm。卷取温度影响FeO的低温转变,卷取温度为561℃时,(Fe+Fe_(3)O_(4))共析组织细小、转变完全;卷取温度为584℃时,共析组织转变量减少,先共析Fe_(3)O_(4)和残余FeO量增加。
The microstructure,mechanical properties and oxide scale evolution of 420 MPa grade thin steel strip under different hot rolling processes were analyzed by using optical microscope and scanning electron microscope.The results show that different cooling rate is the main reason for the difference in microstructure and mechanical properties of steel strip.Under low temperature rolling and rapid cooling process,the microstructure of the strip steel at edge area presents medium-temperature transition characteristics,the transverse structure is different obviously.The yield strength of the steel strip is 458 MPa,the elongation is 26.46%.Under high temperature rolling and slow cooling mode,the uniformity of transverse microstructure is improved,and the yield strength is decreased by 25 MPa,the elongation is increased by 2.50%.The process route of low temperature rolling and rapid cooling inhibits the high temperature oxidation of Fe;O;,and the thickness of iron oxide in the middle of strip steel is 1.13μm less than that produced under high rolling temperature and low cooling rate process.Coiling temperature affects the low temperature transformation of FeO.When the coiling temperature is 561℃,the(Fe+Fe_(3)O_(4))eutectoid structure is fine and its transformation is full.When the coiling temperature is 584℃,the transformation amount of eutectoid structure is decreased,while the amount of proeutectoid Fe_(3)O_(4)and residual FeO is increased.
作者
王恩睿
陈子刚
李斌
李红俊
申震
WANG Enrui;CHEN Zigang;LI Bin;LI Hongjun;SHEN Zhen(Technology Center ofHBIS Group Hansteel Company,Handan 056015,China)
出处
《热加工工艺》
北大核心
2022年第11期27-31,共5页
Hot Working Technology
基金
河北省重大科技成果转化项目(19011026Z)
河北省科技计划项目(206Z1009G)。
关键词
热轧工艺
薄带钢
氧化铁皮
hot rolling process
thin steel strip
oxide scale
