Aluminium alloys is desirable for the automotive and electronic appliances industries due totheir high strength-to-weight ratio, corrosion resistance and weldability. Howeverapplications of the aluminium alloys were very difficult because aluminium alloys formabilityis very low at room temperature, despite their advantages. One of the high speed formingtechnologies is Electromagnetic Metal Forming (EMF), which can be useful forming methodfor low formability light-weight materials such as aluminium, magnesium alloys in overcomingthe limitations of conventional forming methods. EMF process refers to the high velocity andhigh strain rate deformation of low-formability materials driven by electromagnetic forces thatare generated by the rapid discharge current through forming coil. This technology dependson the properties of the sheet metal, as well as the process factors such as electromagneticforce in a practical forming operation. Moreover selection of proper shape of forming coil ismost important to achieve the desired deformation using the EMF process. Therefore, thepurpose of this study is to analyse of the dynamic behaviours on workpiece according tovarious forming coil shape with aluminium alloys. To achieve these objectives, a magneticpulse forming system consisting of a 24kJ electromagnetic power source and a bar-type andhelical-type forming coil was employed in an experiment. Then, deformation depth wasmeasured for analyse dynamic behaviours on workpiece. The results showed that as theelectromagnetic force increases, surface damage to part of the workpiece will increase andaccording to the shape of forming coil, distribution of electromagnetic force applied onworkpiece is changed in EMF process.
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