Effective of Surface Active Elements on the Selective Oxidation of Fe-Mn and Fe-Si Alloys

为了减少运输部门的温室气体排放，提高车辆燃料效率的立法要求正在推动汽车制造商在保持车辆安全性和耐用性的同时减轻车辆重量。为了实现这一目标，制造商在其设计中采用越来越多的先进高强度钢，使得材料比强度可以增加，材料横截面可以减小。然而，使用减小的横截面增加了对钢的腐蚀保护的需求，以保持车辆的完整性、安全性并满足消费者的耐久性期望。通过连续镀锌（CGL）工艺应用的锌（Zn）基金属涂层是实现这一目标的最具成本效益的方法。然而，最新等级的先进钢具有更高的合金含量，这使得反应性润湿和强涂层粘附的过程困难，这是由于合金元素主要是锰（Mn）和硅（Si）在CGL过程中的选择性氧化。有几种方法可以克服这一困难，使用内氧化，在基材内部形成有害的氧化物，留下良好的表面，并使用表面活性元素，如少量添加锡（Sn）或两者的组合，目前McDermid研究小组正在研究下一代高合金先进钢。本提案试图解决下一代先进钢Mn和Si中的主要合金化元素对表面活性合金化添加物（特别是Sn）在改变外部氧化物形态以使得基材与CGL工艺相容方面的功效的影响的基本问题。本次调查的结果将与McDermid在下一代先进钢材设计方面的其他活动相结合，使其既与连续镀锌工艺兼容，又能满足汽车材料行业日益苛刻的性能目标。该项目将培养两名博士级研究人员，他们将拥有表面和性能导向钢设计的先进知识，这将有助于加拿大制造商生产更轻，更安全，可持续，省油的车辆，并有助于促进未来的知识型和可持续制造业。

The legislative requirements for increased vehicle fuel efficiency in order to decrease transportation sector greenhouse gas emissions is driving automotive manufactures to reduce vehicle weight while maintaining vehicle safety and durability. To achieve this goal, manufacturers are employing increasing amounts of advanced high strength steels in their designs such that material specific strength can be increased and material cross-sections reduced. However, the use of reduced cross-sections increases the need for corrosion protection of the steels in order to maintain vehicle integrity, safety and meet consumer durability expectations. Zinc (Zn)-based metallic coatings applied by the continuous galvanizing (CGL) process is the most cost effective means of achieving this goal.***However, the newest grades of advanced steels have higher alloy contents, which make the process of reactive wetting and strong coating adherence difficult due to alloy element mainly manganese (Mn) and silicon (Si) selective oxidation in the CGL process. There are several means of overcoming this difficulty, with the use of internal oxidation in which harmful oxides are formed inside the substrate, leaving a good surface and the use of surface active elements, such as small additions of tin (Sn), or combinations of the two, being currently under investigation by the McDermid research group for the next generation of highly alloyed advanced steels.***The present proposal seeks to address the fundamental question of the effect of the primary alloying elements in the next generation of advanced steels Mn and Si on the efficacy of surface active alloying additions, in particular Sn, in altering the external oxides morphology such that the substrates are compatible with the CGL process. The findings of this investigation will be leveraged with McDermid's other activities on the design of the next generation of advanced steels such that they are both compatible with the continuous galvanizing process and meet the increasingly demanding property targets of the automotive materials sector. This project will train two PhD level researchers who will have advanced knowledge of surface and property oriented steel designs, and which will help enable Canadian manufacturers to produce lighter, safer, sustainable, fuel efficient vehicles and which will help promote the knowledge-based and sustainable manufacturing sector of the future.**