摘要
文中采用一种碳含量为0.6%的高碳钢盘条,利用连续拉拔机和水箱拉丝机分别将Ф5.5 mm盘条拉拔至Ф2.5 mm和Ф1.45 mm。研究了原始盘条和拉拔钢丝的显微组织和力学性能的变化,同时与K·Д·波捷姆金经验公式进行了对比分析。研究结果表明:盘条热轧态显微组织主要为索氏体和少量的先共析铁素体,铁素体沿原奥氏体晶界分布,渗碳体片层随机分布,芯部显微组织中铁素体含量明显较高。随着拉拔减面率的增加,先共析铁素体逐渐变细小,沿拉拔方向呈条状分布。渗碳体片层逐渐向拉拔方向转动,沿着拉拔方向被拉长,渗碳体片层间距明显减小,当拉拔减面率达到93.05%时,形成典型的纤维状组织。随着拉拔减面率的增加,盘条抗拉强度和硬度明显增加,断面收缩率和伸长率逐渐降低,这与拉拔过程中组织的变化有关。与K·Д·波捷姆金经验公式计算结果相比,盘条拉拔后抗拉强度增量略微偏低,这与原始盘条的组织中索氏体含量和均匀性有关,拉拔钢丝再次拉拔后抗拉强度增量与K·Д·波捷姆金经验公计算结果基本一致。
In this paper,a type of high carbon steel wire with 0.6%carbon content is drawn from Ф5.5 mm to Ф2.5 mm and Ф1.45 mm respectively by continuous drawing machine and water tank drawing machine.The microstructure and mechanical properties of the original wire and the drawn wire are studied to observe the changes,which is then compared with the empirical formulas K·Д·Potemkin.The results show that the microstructure of hot-rolled wire mainly includes sorbite and a small amount of proeutectoid ferrite.Ferrite distributes along the austenite grain boundary.Cementite layers are randomly distributed.The ferrite content in core microstructure is obviously higher.With the increase of drawing reduction ratio,the proeutectoid ferrite gradually fines and distributes in strips along the drawing direction.The cementite layers rotate towards the drawing direction gradually,and are elongated along the drawing direction.The distance between cementite layers decreases obviously.When the drawing reduction ratio reaches to 93.05%,typical fibrous structure forms.With the increase of drawing reduction rate,the tensile strength and hardness of wire increase obviously,and the reduction of area and elongation decrease gradually,which is related to the change of microstructure during drawing process.Compared with the calculation results of empirical formulas K·Д·Potemkin,the increment of tensile strength of the wire after drawing is slightly lower,which is related to the content and uniformity of sorbite in the original wire.The increment of tensile strength after redrawing is basically consistent with the calculation results of empirical formulas K·Д·Potemkin.
作者
李成良
雷中钰
寻忠忠
黄新发
LI Chengliang;LEI Zhongyu;XUN Zhongzhong;HUANG Xinfa(Baowu Group Guangdong Shaoguan Iron and Steel Co.,Ltd.,Shaoguan 512123,Guangdong,China)
出处
《江西冶金》
2020年第5期34-39,共6页
Jiangxi Metallurgy
关键词
高碳钢盘条
冷拉拔
索氏体
微观组织
力学性能
high carbon steel wire
cold drawing
sorbite
microstructure
mechanical property
