590 MPa级冷轧低合金高强钢表面色差分析

Analysis of Surface Color Difference of 590MPa Cold Rolled Low Alloy High Strength Steel

随着汽车轻量化的要求,高强钢在汽车产业中应用越发广泛。针对在生产冷轧低合金高强钢的过程中遇到的色差不良问题,分析色差产生的原因:一是退火炉炉内气氛异常,导致铁元素氧化生成氧化色产生色差。这种情况通过降低退火炉氧气含量、降低露点、提高氢气浓度可以避免。另是高强钢的合金元素锰元素,因高温在钢板表面富集导致的色差,此种情况因钢板成分所致,较难避免。经实验分析,有色差钢板的拉伸性能、化学处理性能符合客户标准,但颜色差异会导致客户疑义,因此实际生产中应尽量避免色差问题。

With the requirements of automobile lightweight,high-strength steel is more and more widely used in automobile,steel mills encounter the problem of poor color difference in the production of cold-rolled low-alloy high-strength steel.After analysis,there are two reasons for the color difference.One is that the abnormal atmosphere in the annealing furnace leads to the oxidation of iron,resulting in the oxidation color and the color difference.In this case,it can be avoided by reducing the oxygen content of the annealing furnace,reducing the dew point and increasing the hydrogen concentration.The other is the color difference caused by the enrichment of manganese on the surface of the steel plate at high temperature,which is difficult to avoid due to the composition of the steel plate.Through experimental analysis,the tensile properties and chemical treatment properties of color difference steel plate meet the customer's standards,but the color difference will lead to customer doubts.Therefore,the problem of color difference should be avoided in actual production.