Incremental forming of sheet metals is a new and suitable method to produce parts in small batches. In this process, by using a simple rotating tool and gradually moving in a predefined path, the sheet will be formed to the desired shape. Since no dedicated die is used, low cost of equipment and also reduction of forming forces, parts with different sizes can be produced with lower cost in comparison with conventional methods like deep drawing. In this research light alloy sheet is experimentally formed by Electric Hot Incremental Forming method and effect of influencing parameters, namely initial sheet thickness, feed rate, spindle speed, tool vertical step size and amount of current passing circuit on formability and maximum forming angle of a frustum with varying wall angle is investigated. Surface quality of produced parts under different conditions and effect of lubrication on reduction of surface roughness, is investigated. To study geometric accuracy, point cloud model of some parts are provided and deviation value between produced and ideal geometry are determined in CATIA software. Hardness of produced parts are measured along depth using Vickers microhardness test and variation of hardness along depth of part are investigated. In addition to experimental tests, hot incremental sheet forming process is simulated in ABAQUS finite element software. To validate modeling, simulated and experimental results including geometry and part thickness are compared and amount of deviation of results is determined. Amount of current entering the circuit has a significant effect on sheet formability and an increase in sheet thickness, increases amount of current required for deformation. Passing very high current through the circuit causes sheet burning and reduction of formability. A decrease in feed rate, step size and spindle speed and also an increase in sheet thickness can increase maximum forming angle. The maximum deviation between desired and formed geometry, occurs at part opening. Roughness of internal surface is higher than external and surface quality is improved by use of lubricant and reduction of step size. The simulated and experimental profiles, as well as thickness distribution are in good agreement. Key Words: Hot Incremental Sheet Forming, Formability, Finite Element Simulation.
