ASSURE 2 - Advanced Steel Shaping Using Reduced Energy

按价值计算，钢铁仍然是世界上使用最多的材料，在社会的各个方面发挥着至关重要的作用，从建筑到运输，从能源生产到粮食生产。随着所有权的变化，英国钢铁行业正在经历重大变革。英国钢铁生产的长期可持续性需要更低的能源生产和高价值钢铁产品的发展。能源占钢铁生产成本的很大一部分，在20%到40%之间，虽然在过去的30年里，通过钢铁制造技术的变化，生产一吨钢铁所需的能源数量减少了50%，但进一步的改进是必要的。钢铁的加热和再加热是钢铁供应链中重要的能源消耗。因此，引入新的加工路线以尽量减少或消除再加热阶段将对能源使用产生巨大影响，并且，如果这与通过铸造到接近净形状来减少热变形相结合，则可以实现进一步的能源减少。本项目旨在建立采用带式铸造技术生产常规和先进高强度钢（AHSS）的工艺和化学窗口。带式铸造是一种近净形铸造工艺，生产的带钢需要最小的热变形来达到所需的产品厚度。与传统的连铸到大断面，然后进行热轧相比，这是一条能耗显著降低的生产路线，例如，每吨钢的能耗可减少300吉焦（基于节省约100吉焦）。2吉焦/吨从减少热轧和大约。1.25 GJ/吨（近净形铸造）。此外，带式铸造允许生产目前无法使用传统工艺生产的AHSS钢牌号：TWIP（孪生诱导塑性）和TRIP（转化诱导塑性）牌号具有高加工硬化率，这意味着它们不能在当前的热轧带钢轧机中轧制；低密度（高铝）钢具有非常大的晶粒尺寸（毫米），导致加工性差（例如，在连铸过程中热撕裂）。这些钢在商业上非常有吸引力，因为它们具有非常优越的性能（TWIP和TRIP钢的强度是传统钢的2倍，延展性是传统钢的3倍，高铝钢具有良好的强度和较低的密度），这有助于汽车和建筑行业的轻量化。在ASSURE可行性项目期间，在WMG建立了设备，可以模拟带铸组织，包括在不同冷却速度下动态直接观察钢的凝固。结果表明，与常规板坯铸造相比，带式铸造的高冷却速度改变了组织，并且通过控制成分可以实现进一步的有益改变（例如高铝钢的晶粒尺寸减小）。在这个项目（ASSURE2）中，将建立成分、工艺参数和微观结构（以及最终产品性能）之间的定量关系，同时考虑到带式铸造的冷却速度更快，并且与传统工艺相比，铸造到最终厚度后的热变形减少。新的概念，如大气控制的成分改变和/或凝固温度的降低和电磁场的微观组织细化也将被考虑。与加拿大麦吉尔大学的Guthrie教授合作，他是带铸造技术和液态金属过程计算建模的领先专家，将为科学研究提供重要的附加价值，分包合同使用他们在MetSim的试验工厂设施，使我们能够考虑从实验室科学研究扩大到工业相关加工。

Steel continues to be the most used material in the world by value and play an essential role in all aspects of society, from construction to transport, energy generation to food production. The UK steel industry is undergoing significant changes with changes in ownership. The long-term sustainability of UK steel making requires lower energy production and the development of high value steel products. Energy constitutes a significant portion of the cost of steel production, between 20% to 40% and, whilst the amount of energy required to produce a tonne of steel has reduced by 50% in the past 30 years through changes in steel making technologies, further improvements are necessary. Heating and reheating steel is responsible for significant energy consumption in the steel supply chain. Therefore the introduction of new processing routes to minimise or eliminate reheating stages will have a dramatic effect on energy use, and, if this is coupled with reduced hot deformation by casting to near net shape, further energy reductions can be realised.This project is concerned with establishing the process and chemistry windows for production of conventional and advanced high strength strip (AHSS) steel grades using belt casting technology. Belt casting is a near net shape casting process, producing strip that needs minimal hot deformation to achieve the required product thickness. It is a significantly lower energy production route compared to traditional continuous casting to large sections with subsequent hot rolling, for example energy consumption could be reduced by > 3 GJ/tonne steel produced (based on savings of approx. 2 GJ/tonne from reduced hot rolling and approx. 1.25 GJ/tonne from near net shape casting). In addition belt casting allows the production of AHSS steel grades that cannot currently be manufactured using conventional processing: TWIP (twinning induced plasticity) and TRIP (transformation induced plasticity) grades have high work hardening rates meaning they cannot be rolled in current hot rolling strip mills; and low density (high Al) steels have very large grain sizes (millimeters) that result in poor processability (e.g. hot tearing during continuous casting). These steels are extremely attractive commercially, given their vastly superior properties (TWIP and TRIP steels are 2x as strong, with 3x the ductility of conventional steels, and high Al steels have a combination of good strength and lower density), which can contribute to light weighting in the automotive and construction industries.During the ASSURE feasibility project facilities were established at WMG to allow simulation belt cast microstructures, including dynamic direct observation of the solidifying steel at different cooling rates. It was shown that the microstructures are altered by the higher cooling rate of belt casting, compared to conventional slab casting, and that further beneficial modifications (e.g. reduction in grain size in high Al steels) can be achieved by composition control. In this project (ASSURE2), quantitative relationships between composition, process parameters and microstructure (and hence final product properties) will be established, taking into account the higher cooling rates of belt casting and the reduced hot deformation after casting to final thickness compared to conventional processing. Novel new concepts, such as atmospheric control for composition modification and / or solidification temperature reduction and electromagnetic fields for microstructure refinement will also be considered. The collaboration with Professor Guthrie at McGill University in Canada, the leading expert on belt casting technology and computational modelling of liquid metal processes, will provide significant added value to the scientific studies, with the subcontract to use their pilot plant facilities, at MetSim, allowing us to consider the scale up from laboratory scientific studies to industrially relevant processing.