In-situ surface analysis for surface engineering in metal forming of lightweight alloys

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The drive towards the application of lightweight materials such as aluminum and magnesium in various industries has led to the need for understanding the tribological interactions that occur during metal forming processes. In fact data from an industrial survey state two of the critical factors influencing metal forming processing are tribology of sheet metal forming and the design of dies. This is because the forming of lightweight metals is hindered by adhesion between these metals and the forming die/tool, which can lead to the reduction of the surface quality of the final product as well as tool life. Current die surface treatments and lubricants are unable to completely prevent this metal/die reaction. Therefore, a better understanding of the tribological interactions that occur between the die and metal is essential. This research seeks to mitigate the interactions by utilizing a multi-aspect tribological approach. The approach will consist of an experimental set-up designed to monitor, analyse and systematically characterise the mechanisms occurring during lubricated sliding contact between the die and workpiece surfaces. The set-up which will incorporate a high depth-of-focus microscope and a micro-Raman spectrometer for direct observation and 3D characterization of metal and die interactions. It will also be equipped with laser triangle sensors for the in-situ measurement and characterisation of the lubricant film which will determine the mechanisms influencing lubrication and COF due to die surface texturing and superposition of ultrasonic waves. Therefore, this experimental set-up will help to establish a novel in-situ technique for the determination and monitoring of lubrication conditions i.e. lubricant thickness and breakdown. The experimental results will also be applied to a plane strain compression set-up equipped with laser triangle sensors and ultrasonic wave transducer/generator system which simulates surface interactions in metal forming processes. The results will confirm the effect of surface texture and ultrasonic waves on deformation characteristics and surface quality especially at varying strains and strain rates at which metal forming occurs. In summary, this research project will establish an in-situ technique for monitoring lubrication film thickness and testing surface textures and ultrasonic waves effects used for friction control that will contribute to the production of surface defect free products in the Canadian metal forming industry. The forming industry will save millions of dollars that are invested to rectify surface defects on lightweight materials induced during metal forming and, therefore, increase their efficiency.**