In situ optical diagnostics for characterizing the coating transformation of aluminized steel during hot stamping

用于表征热冲压过程中渗铝钢涂层转变的原位光学诊断

• 批准号: 555905-2020
• 负责人: Daun, KyleKJ
• 金额: $ 1.63万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=760337
• 关键词: situ; optical; diagnostics; characterizing; coating

Cosma International, one of Canada's largest automotive parts manufacturers, makes high strength automotive parts through hot stamping. In this procedure, ultrahigh strength steel blanks are first austenitized in a roller hearth furnace and then transferred to a water-cooled die, where the parts are simultaneously quenched and formed into shape. The blanks have a thin aluminum/silicon coating that prevents the steel from oxidizing and decarborizing in the furnace. The coating melts and reacts with iron from the steel to form a permanent Al-Si-Fe intermetallic layer that provides some long term corrosion protection, but may also impair welding assembly if it grows too thick. Both the radiative properties of the steel, which determines the blank heating rate, and the surface texture, which affects die quenching rates and paint adhesion, also evolves with heating time. The present state-of-knowledge about coating evolution comes almost entirely from ex situ analysis of coupons that have been heated in the furnace, extracted, and quenched, but the temporal resolution of this procedure is limited and quenching alters the coating texture. This research will deploy a new suite of optical diagnostics, including laser speckle analysis, Fourier-transform infrared spectroscopy, and 3D Raman spectroscopy, to provide continuous in situ measurements of the Al-Si coating as it transforms with heating. These measurements will be used to derive a coating evolution model that will allow Cosma to optimize furnace-based hot stamping operations, adopt their techniques to new materials, and develop entirely new manufacturing processes

Cosma International 是加拿大最大的汽车零部件制造商之一，通过热冲压生产高强度汽车零部件。在此过程中，超高强度钢毛坯首先在辊底炉中进行奥氏体化，然后转移到水冷模具中，零件在其中同时淬火并成型。毛坯具有薄薄的铝/硅涂层，可防止钢在炉中氧化和脱碳。涂层熔化并与钢中的铁发生反应，形成永久的 Al-Si-Fe 金属间化合物层，提供一些长期的腐蚀保护，但如果它变得太厚，也可能损害焊接组件。决定毛坯加热速率的钢的辐射特性和影响模具淬火速率和油漆附着力的表面纹理也会随着加热时间而变化。目前有关涂层演变的知识几乎完全来自对在炉中加热、提取和淬火的试样进行的异位分析，但该过程的时间分辨率有限，并且淬火会改变涂层纹理。这项研究将部署一套新的光学诊断技术，包括激光散斑分析、傅里叶变换红外光谱和 3D 拉曼光谱，以在 Al-Si 涂层因加热而变形时提供连续的原位测量。这些测量结果将用于推导涂层演化模型，使 Cosma 能够优化基于熔炉的热冲压操作，将其技术应用于新材料，并开发全新的制造工艺