摘要
为满足制丝行业对大规格高强高塑性线材原料的需求,研发了青钢高速线材轧机多功能在线盐浴热处理(QMIT)工艺,并研究了QMIT工艺参数对Fe-C-Mn-Si高碳钢显微组织、力学性能和氧化铁皮的影响规律。与传统风冷工艺相比,QMIT大幅降低了粗大珠光体、先共析渗碳体、游离铁素体、离异珠光体和芯部马氏体等异常组织的产生概率。大规格高强度高塑性YL82B线材抗拉强度为1215~1325 MPa,断面收缩率为40%~48%,抗拉强度通圈差小于35 MPa。QMIT盘条氧化铁皮分为2层,白亮的外层为Fe_(3)O_(4),灰色的内层为FeO,内层FeO层上有球状或者岛状的Fe_(3)O_(4)。随着盐浴温度的升高,氧化铁皮的厚度基本一致,但内层FeO中分布的岛状先共析Fe_(3)O_(4)的尺寸和数量明显增大。综合来看,采用较低的盐浴温度既能获得良好的显微组织和力学性能,又能获得适于机械剥壳的氧化铁皮。
In order to meet the demand of wire making industry for raw materials of thick diameter,high strength and high plasticity wire rods,Qinggang Multi-purpose In-line heat Treatment with salt bath(QMIT)process was developed and the influence of QMIT process parameters on microstructure,mechanical properties and scale of Fe-C-Mn-Si high carbon steel wire rod was studied.Compared to the traditional air-cooling process,QMIT process greatly reduces the occurrence rate of abnormal structures such as coarse pearlite,proeutectoid cementite,free ferrite,divorced pearlite and martensite in the center of wire rod.The YL82B wire rod can obtain ultra-high tensile strength of 1215-1325 MPa combined with the reduction of area of 40%-48%after QMIT processing.Moreover,the difference of tensile strength for all tested samples taken from one coil of wire rod is less than 35 MPa.The iron oxide scale of QMIT wire rod is divided into two layers,of which the white and bright outer layer is Fe_(3)O_(4),and the gray inner layer is FeO.In addition,spherical or island proeutectoid Fe_(3)O_(4)with different quantities and sizes are distributed in the inner FeO layer.With the increase of salt bath temperature,the thickness of scale layer retains the same basically,but the size and quantity of island proeutectoid Fe_(3)O_(4)distributed in the inner FeO layer increase significantly.In general,QMIT process can obtain wire rods with good microstructure and mechanical properties and oxide scale easy to mechanical descaling under lower salt bath temperature.
作者
李阳
甄先锋
王广顺
郑同亮
徐凯
LI Yang;ZHEN Xian-feng;WANG Guang-shun;ZHENG Tong-liang;XU Kai(Qingdao Branch,CITIC Pacific Special Steel Research Institute,Qingdao 266409,Shandong,China;Wire Rod Research Institute,Qingdao Special Steel Co.,Ltd.,Qingdao 266409,Shandong,China)
出处
《中国冶金》
CAS
CSCD
北大核心
2023年第4期104-110,共7页
China Metallurgy
关键词
高速线材
多功能在线盐浴热处理
超高强度
塑性
氧化铁皮
high-speed wire
multifunctional in-line salt bath heat treatment
ultra-high strength
plasticity
iron oxide scale
