Manufacturing process optimisation for high performance electrical steels for low emission advanced electric drivetrains in automotive applications

Lead Research Organisation: University of Sheffield
Department Name: Mechanical Engineering

Abstract

Silicon (Si) is one of the main alloying elements in steels used to promote magnetic properties in electrical steels. The high Si content and the thin sheets with thicknesses as low as 0.1 mm, provide the highest magnetic quality final products. However, there are many unknowns about micromechanical properties of high Si content electrical steels. Additionally, several challenges are involved in the production of these steels grades as the presence of Si leads to a reduced formability that makes the material prone to unexpected brittle fracture at several stages during the production. The proposed project aims to develop a manufacturing methodology to be used by Cogent Power to convert electrical steels with 3.2% Si content, produced by Tata Steel hot strip rolling mill at Port Talbot site, into highest quality electrical steels with a thickness of about 0.1 millimetres.

Understanding the mechanical and metallurgical properties of the material at different conditions is the first step to predict their deformation behaviour during a manufacturing process and develop required predictive models. Bespoke experimental setups will be designed in order to investigate and determine the deformation and damage mechanics/mechanisms involved in the hot and subsequent cold rolling operations of the selected material. Multi-scale mechanical tests will be performed to measure microstructural deformation during hot rolling process.

The hot rolling process will be experimentally simulated in order to get a better insight into micro-mechanism of deformation and microstructural evolution during hot rolling of 3.2% Si electrical steel. Thermo-mechanically coupled Finite Element models will be developed to predict formability and damage initiation/evolution in the selected material for different stage of manufacturing operations to be used in Tata Steel Port Talbot site in South Wales. The developed models will be validated using laboratory rolling experiments at Tata Steel facilities within the UK and Europe.

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