【作者】 李小舟；

【导师】 马云辉；

【作者基本信息】 哈尔滨工业大学 ， 工业工程（专业学位）， 2020， 硕士

【摘要】 汽车以其方便、快捷的特性,作为当今社会人们生活中不可缺少的交通工具。汽车制造发展到今天,安全、环保、轻量化成为汽车工业的的发展趋势。影响汽车自身减重最大的因素是汽车用钢板的重量,因而,为了在确保安全的前提下制造轻量化高强钢,作为各钢材生产商研制开发的第一要务。本文研究的烘烤硬化钢就是轻量化高强钢板中最重要的一种。本文首先描述了烘烤硬化钢的特性,即钢板轧制退火后,具有较低屈服强度,易于冲压成形,而在经过涂漆烘烤后屈服强度升高,从而具有较高强度,大大提高抗冲击性能的钢种。通过对比实验的方法,讨论了烘烤时间、预变形对烘烤硬化值的影响,得出烘烤硬化值会随烘烤时间而变大,但到一定数值后将不再增加,也得出预变形量为2%时烘烤硬化值达到最大。本文主要通过采用多组实验钢进行对比实验,对烘烤硬化钢的再结晶动力学,析出物的溶解析出规律,再结晶织构和固溶元素的分布进行了研究。得出钒元素的存在能加快烘烤硬化钢再结晶的速度、提高烘烤硬化值、减小再结晶晶粒尺寸。同时得出含钒烘烤硬化在较低退火温度和较短退火时间的条件下,能够获得相对高强度的有利{111}织构和相对低强度的不利{100}织构,这说明含钒烘烤硬化钢在相对较低退火温度和相对较低的退火时间下,比较有利于提高深冲压性能。最后,根据本文所研究得出的结论,经过生产工艺设计和工厂的实际生产,成功生产出180BH等多个强度级别的烘烤硬化钢,并且分析了影响产品性能均匀性的多个因素和易导致钢板产生板形不良的因素。更多还原

【Abstract】 Automobile is an indispensable means of transportation because of its convenience and rapidity in people’s life nowadays.With the development of automobile manufacturing today,safety,environmental protection and light weight have become the development trend of automobile industry.The biggest factor affecting the weight loss of automobile is the weight of automobile steel plate.Therefore,in order to ensure the safety of the premise of manufacturing lightweight high-strength steel,as the first priority of the development of various steel manufacturers.The baking hardening steel is one of the most important lightweight high strength steel plates.This paper first describes the characteristics of bake hardening steel,that is,steel plate has lower yield strength and is easy to press and form after rolling and annealed,while the yield strength increases after baking and coating,so it has higher strength and greatly improves the impact resistance.By the methods of contrast experiment,discusses the baking time,pre deformation on the bake hardenability value,the influence of the bake hardenability value will be bigger as the baking time increased and the baking hardening value reached the maximum when the predeformation was 2%.In this paper,the recrystallization kinetics,dissolution and precipitation law,recrystallization texture and distribution of solid solution elements of baking and hardening steel were studied by comparing several groups of experimental steels.It is concluded that the presence of vanadium can accelerate the recrystallization rate,increase the bake hardening value and reduc e the recrystallization grain size.Obtained at the same time containing vanadium bh at lower annealing temperature and annealing time is shorter under the condition of,can obtain relatively high intensity of {111} texture and relatively low intensity of {100} texture,so that vanadium bake hardening steel at relatively low annealing temperature and annealing time is relatively low,is advantageous to improve deep drawing performance.Finally,according to the conclusions obtained in this paper,after the production process design and the actual production in the factory,the baking and hardening steel of 180 BH and other strength levels were successfully produced,and the factors affecting the uniformity of product performance and causing the poor shape of the steel plate were analyzed.更多还原