降低低碳钢板坯高温氧化烧损的研究

发布时间：2018-05-22 18:05

  本文选题：钢坯 + 氧化烧损　； 参考：《华北理工大学》2017年硕士论文

【摘要】：钢坯在热成型、尤其加热工段,由于加热温度高、时间长,氧化是难以避免的问题,而且也是引起钢材耗损的重要原因。因此,研究钢坯在高温下的氧化烧损机理,探索一条工业生产中控制钢坯氧化烧损的有效途径,对指导企业节能降耗,产品质量和生产技术升级以及可持续发展具有重要意义,对我国这样一个钢铁大国,经济和社会效益也十分明显。通过降低加热炉中的氧分压的技术途径来减少钢坯的氧化烧损进行系统而深入的研究。选取了三种钢样,牌号分别为08Al、SPHD、Q195。氧分压(Po2)选择以下三种:4%(模拟工况Po2),21%(空气中,大于工况Po2)和0.1%(氮气中,小于工况Po2);氧化温度模拟轧钢厂的加热炉温度(1150-1250℃)。通过对钢坯随Po2降低的氧化动力学行为研究,并对氧化层及相关区域的化学和相组成、组织结构以及形貌特征进行了详细分析,获得主要结果如下:不同钢种在相同Po2下的氧化机理(氧化动力学、烧损和氧化皮结构等)不同,钢种成分(尤其含碳量)相差越大,则差异越明显。三种钢在高温下形成的氧化皮以存在大量孔洞和裂纹等缺陷的Fe O层为主体,冷却过程中向Fe3O4甚至Fe2O3转变。转变速度与冷却速度成反比,转变程度与钢种成分有关。Po2是影响氧化烧损最主要的因素,降低Po2能显著降低钢坯氧化烧损。所有钢种在三个温度(1150、1200及1250℃)下都符合氧化动力学随Po2降低而显著降低的规律。1250℃时,Po2从工况4%降到0.1%时,三种钢的烧损可降低70-95%,换算成钢坯的氧化烧损值0.5%,完全达到了合同中降至1%以下的技术目标。1200和1150℃,通过降低Po2使钢的烧损至少降低了75%以上,换算成得烧损值要小于0.4%,也完全满足合同目标。降低加热温度能有效降低钢坯氧化烧损。在4%O2条件中,温度从1250℃降低50℃,08Al烧损减少了12%,SPHD和Q195则在20%以上。温度再降低50℃,08Al的烧损与1250℃相比降低了24%,SPHD减少了30%,Q195则为40%以上。相比之下,降低Po2比降低温度更有效地减少了钢坯的氧化烧损。
[Abstract]:Due to the high heating temperature and the long time, the oxidation of steel billet in hot forming, especially in heating section, is an unavoidable problem, and it is also an important cause of steel wastage. Therefore, it is of great significance to study the oxidation burning mechanism of steel billet at high temperature and to explore an effective way to control the oxidation burning loss of steel billet in industrial production. It is of great significance to guide enterprises to save energy and reduce consumption, upgrade product quality, production technology and sustainable development. To our country such a big country of iron and steel, economic and social benefit is also very obvious. By reducing the oxygen partial pressure in the heating furnace to reduce the oxidation loss of steel billet is studied systematically and deeply. Three kinds of steel samples were selected, and their grades were 08AlN SPHD Q195. Three kinds of oxygen partial pressure (Po2) are selected as follows: 1: 4 (in the air, larger than the operating condition Po2) and 0.1 (in nitrogen, less than that in the working condition); the oxidation temperature simulates the furnace temperature of 1150-1250 鈩，

本文编号：1923095