Cooling Effects in Multiscan Laser Forming
نویسنده
چکیده
For laser forming of sheet metal to become a practical production or rapid prototyping tool, multiscan, that is, to use a laser to scan the workpiece repeatedly is necessary in order to achieve the required magnitude of deformation. Between consecutive scans, substantial waiting time is normally necessary for the workpiece to cool down in order for a steep temperature gradient to be reestablished in the next scan. In this paper, cooling effects under various conditions including different laser power, scanning speed, nozzle offset and cooling air pressure are investigated. Cooling effects on microstructure change and other mechanical properties including strength, ductility and hardness are also examined. The investigation on multiscan laser forming shows forced cooling has the potential to significantly reduce the total forming time while having no undesirable effects on microstructure change and other mechanical behavior. The established numerical model for laser forming with forced cooling provides greater insights into the cooling effects on deformation mechanism, helps predict such effects on final dimensional accuracy and mechanical properties, and can be extended to optimize the multi-scan laser forming process.
منابع مشابه
Microstructure Integrated Modeling of Multiscan Laser Forming
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