【作者】 王维；

【导师】 杜林秀；

【作者基本信息】 东北大学 ， 材料工程（专业学位）， 2018， 硕士

【摘要】 热轧层流冷却过程对产品性能有重要作用。一直以来宝钢2050热轧不具备轧制过程中温度均匀性变化检测设备,在层流冷却过程中缺乏宽度方向上温度分布均匀性控制装置,无法开展热轧生产过程中的温度均匀性对产品性能影响等相关技术的研究,没有该方面的技术积累。产品制造一贯制中仅提出了对带钢中部的终轧温度、卷取温度等要求。另一方面,分析热轧发生的五类用户异议:1)横向组织均匀性有待提高;2)严重的制耳,对模具造成损伤;3)冲压时带钢边部易开裂;4)边部存在边浪,纵剪后表面严重横向折痕;5)两边浪形无法矫平需切除等,其产生都可追溯到带钢边部,与带钢宽度方向的温度不均匀密切相关,因此迫切需要解决热轧带钢冷却温度均匀性问题。而通过2010年年修完成的2050热轧层流冷却边部温度控制装置的技术改造,具备了一定的层流冷却温度均匀性控制手段。本论文通过改造后设备的控制能力、设备控制方式、所适品种以及温度均匀性对产品性能的影响等方面的研究,产品的断面温度均匀性得到明显的改善,组织差异明显减小,由此带来了以下方面产品质量的改善,包括冷轧向宽板的边裂缺陷得到明显的改善,冷轧向高强钢的边部板型的改善等等,从而有效提升了 2050产线产品质量和竞争力,并产生了以下成果:(1)通过温度变化趋势的判定,来确认带钢最边部的温度值,并为后续研究打下基础;(2)通过选取典型的冷轧、热轧品种进行冷却模拟实验,包括在不同温度下降低冷却速率进行模拟,并对模拟后样品的组织及性能进行分析,发现在不同的温度降低冷却速率会造出截然不同的效果,原则上需避开相变区降低边部的冷却速率,如此可以有效改善组织均匀性,否则效果适得其反;(3)在2050目前的产品中,部分对边部组织敏感的品种在投入边部遮蔽后质量有较为明显的改进。更多还原

【Abstract】 Laminar cooling of hot rolling plays an important role in the performance of the products.Baosteel hot rolling has no temperature uniformity change test equipment during rolling,In the laminar cooling process,there is no uniform temperature distribution control device in the width direction,It is impossible to carry out the research on the temperature uniformity in hot rolling process and the influence on the product performance There is no technological accumulation in this respect.In the system of product manufacture,the rolling temperature and coiling temperature in the middle part of the strip have been put forward only.On the other hand,five types of user objections for hot rolling are analyzed:1)The uniformity of lateral structure needs to be improved;2)Severe ear damage to the mold;3)The edge of strip is easy to crack when stamping;4)There are side waves at the edge,and severe transverse creases on the surface after the longitudinal shearing;5)Both sides of the wave cannot be straightened and need to be removed,their cause of formation can be traced back to the strip edge,closely related to uneven temperature in strip width direction.Therefore,it is urgent to solve the problem of cooling temperature uniformity of hot strip steel.In 2010,2050 hot strip completed cooling side temperature control device of the technical transformation,has a certain temperature uniformity of the laminar cooling control method.By this article,the control ability through the transformation of equipment,equipment control,research the variety and uniformity of temperature effect on the performance of the product of the cross section the temperature uniformity of the products are obviously improved,organizational differences significantly reduced,resulting in the improvement of product quality:the width of plate edge crack of cold rolling strip has been improved obviously;the edge shape of high strength steel of cold rolling strip has been improved.Thus,it effectively improves the quality and competitiveness of 2050mm line products.Based on the above research work,the following conclusions are drawn:(1)Confirm the temperature value of the most edge of strip by judging the trend of temperature change,and lay a foundation for further research.(2)Through the typical cold rolling,hot rolling varieties for cooling simulation experiments,including at different temperatures with different cooling rates were simulated,and the performance and sample microstructure simulation was analyzed.It was found that the lower cooling rate will produce different effects in different temperature,in principle,to avoid reducing the cooling phase transformation zone the rate of the edge,so can effectively improve the uniformity of microstructure,otherwise counterproductive;(3)In the 2050 current products,some of the varieties with sensitive border tissue have improved quality when they are covered by edges.更多还原