X70QS无缝管线钢管连续冷却转变规律的研究  

Research on Continuous Cooling Transformation of X70QS Seamless Pipeline Steel

作　　者：黄电源[1] 邹喜洋[1] 

机构地区：[1]衡阳华菱钢管有限公司技术中心,湖南衡阳421001

出　　处：《金属材料与冶金工程》2015年第2期16-19,共4页Metal Materials and Metallurgy Engineering

摘　　要：介绍了衡阳华菱钢管有限公司利用Gleeble 1500热模拟试验机研究X70QS无缝管线钢管在不同冷却条件下组织及显微硬度的变化规律,绘制了试验条件下X70QS无缝管线钢管的CCT曲线。试验结果表明,随着冷却速度的提高,X70QS无缝管线钢的微观组织由多边形铁素体（PF）逐渐向针状铁素体（AF）转变。实验室条件下,X70QS无缝管线钢以40~60℃/s冷却后能得到以细小均匀的针状铁素体为主的理想组织,并且针状铁素体晶粒内弥散分布一定数量的细小M/A岛状组织。这种AF＋M/A的混合组织结构能有效地提高材料的强度和韧性。By using Gleeble 1 500 thermal simulator, Hengyang Valin Steel Tube Co., Ltd.investigated the variation rules of microstructure and micro-hardness of the X70 QS seamless pipeline steel under different cooling conditions, and drew CCT curve of the pipeline steel under the test conditions. The results show that the microstructure of the pipeline steel gradually transforms from polygonal ferrite（PF） to acicular ferrite（AF） with the increase of cooling rate.Under laboratory conditions, the microstructure of fine and uniform acicular ferrite can be obtained after cooling at 40 to 60 ℃ / s. Furthermore, a certain amount of fine and island-1ike M / A distributes in the ferrite grains. This AF ＋M / A mixed microstructure can improve the strength and toughness of X70 QS seamless pipeline steel.

关 键 词：X70QS无缝管线钢管 CCT曲线 针状铁素体 M/A岛 

分 类 号：TG142.41[一般工业技术—材料科学与工程]