Experimental Investigation of Incremental Forming Process of Bilayer Hybrid Brass/St13 Sheets

Document Type: Original Article


Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran


In this study, the incremental forming of two layers’ brass/St13 sheets through the single-point process was experimentally examined. To investigate the formability of sheet in this process, the desired shape was designed through solid works software, and then surf cam application was used to observe tool motion and extraction of CNC program. G-codes were transferred to the CNC machine and the incremental bilayer sheets forming process was carried out in two different modes, that is, in one case, the brass sheet was placed on top and the steel sheet below, and in the other case they exchanged places. Afterwards, the effects of parameters such as forming tool diameter, vertical step size, and feed rate at three levels on fracture height, fracture angle, and strain were studied. In order to minimize the experiments, the experiment design based on response surface method (RSM) was employed. The results indicated that by increasing the tool diameter, vertical step, feed rate, the fracture angle, and fracture height decreased. The maximum fracture height and angle were estimated 46.5 mm and 71.44 degree, respectively, with tool diameter of 10 mm, speed of 1800 mm/min, and vertical step size of 0.25 mm. According to strain measurement results, steel sheets could bear higher strain rate than brass sheets, and in the case that the steel sheet was on top, the fracture height of bilayer sheet increased. The maximum strain of 0.72 was obtained in SB mode with tool diameter of 10 mm, feed rate of 1000 mm/min and vertical step of 0. 5.


[1]     Gulati, V., Kathuria, S., Katyal, P., “A Paradigm to Produce Customized Ankle Support Using Incremental Sheet Forming”, Engineering and Technology, Vol. 5, No. 1, 2016, pp. 14-18.

[2]     Castaneda, E., Lauret, B., Lirola, J. M., and Ovando, G., “Free-form Architectural Envelopes: Digital Processes Opportunities of Industrial Production at a Reasonable Price”, Facade Design and Engineering, Vol. 3, No. 1, 2015, pp. 1-13.

[3]     Rous, P., U. S. Patent Application for a “Machines for Shaping Sheet Metal”, Publication No. US2945528 A, filed 19 Jul, 1960.

[4]     Leszak, E., U. S. Patent Application for a “Apparatus and Process for Incremental Dieless Forming”, Publication No. US3342051 A, filed 19 Sep, 1967.

[5]     Matsubara, S., “Incremental Backward Bulge Forming of a Sheet Metal with a Hemispherical Head Tool-A Study of a Numerical Control Forming System II”, Japan Society for Technology of Plasticity, Vol. 35, 1994, pp. 1311-1311.

[6]     Emmens, W. C., Sebastiani, G., Boogaard A. H., “The Technology of Incremental Sheet Forming – A Brief Review of the History”, Materials Processing Technology, Vol. 210, No. 8, 2010, p. 981-997.

[7]     Shim, M. S., Park, J. J., “The Formability of Aluminum Sheet in Incremental Forming”, Materials Processing Technology, Vol. 113, No. 1-3, 2001, pp. 654–658.

[8]     Filice, L., Fratini, L., and Micari, F., “Analysis of Material Formability in Incremental Forming”, CIRP Annals - Manufacturing Technology, Vol. 51, No. 1, 2002, pp. 199-202.

[9]     Fratini, L., Ambrogio, G., Di Lorenzo, R., Filice, L., and Micari, F., “Influence of Mechanical Properties of the Sheet Material on Formability in Single Point Incremental Forming”, CIRP Annals-Manufacturing Technology, Vol. 53, N0. 1, 2004, pp. 207-210.

[10]  Jeswiet, J., Young, D., “Forming Limit Diagrams for Single-Point Incremental Engineers of Aluminum Sheet”, Engineering Manufacture, Vol. 219, No. 4, 2005, pp359-364.

[11]  Martins, P., Bay, N., Skjodt, M., and Silva, M., “Theory of Single Point Incremental Forming”, CIRPAnnals-Manufacturing Technology, Vol. 57, No. 1, 2008, pp. 247-252.

[12]  Luo, Y., He, K., and Du, R., “A New Sheet Metal Forming System Based on the Incremental Punching”, The International Journal of Advanced Manufacturing Technology, Vol. 51, No. 5, 2010, pp. 481-491

[13]  Luo, Y., He, K., and Du, R, “A New Sheet Metal Forming System Based on the Incremental Punching”, The International Journal of Advanced Manufacturing Technology, Vol. 51, No. 5, 2010, pp. 493-506.

[14]  Tisza, M., Panity, I., and Kovács, P. Z., “Experimental and Numerical Study of a Milling Machinebased Dieless Incremental Sheet Forming”, International Journal of Material Forming, Vol. 3, No. 1, 2010, pp. 971-974.

[15]   Henrard, C., Bouffioux, C., Eyckens, P., Sol, H., Duflou, J. R., Van Houtte, P., Van Bael, A., Duchêne, L., and Habraken, A. M., “Forming Forces in Single Point Incremental Forming: Prediction by Finite Element Simulations, Validation and Sensitivity”, Computational Mechanics, Vol. 47, No. 5, 2011, 573-590.

[16]  Leóna, J., Salcedoa, D., Ciáurriza, C., Luisa, C.J., Fuertesa, J.P., Puertasa, I., and Luria, R., “Analysis of the Influence of Geometrical Parameters on the Mechanical Properties of Incremental Sheet Forming Parts”, Procedia Engineering, Vol. 63, 2013, pp. 445-453.

[17]  Senthil, R., Gnanavelbabu, A., “Numerical Analysis on Formability of AZ61A Magnesium Alloy by Incremental Forming”, Procedia Engineering, Vol. 97, 2014, pp. 1975-1982.

[18]  Xu, D., Lua, B., Cao, T., Chena, J., Long, and H., Cao, J., “A Comparative Study on Process Potentials for Frictional Stir- and Electric Hot-Assisted Incremental Sheet Forming”, Procedia Engineering, Vol. 81, 2014, pp. 2324-2329.

[19]  Mugendirana, V., Gnanavelbabub, A., “Comparison of FLD and Thickness Distribution on AA5052 Aluminium Alloy Formed Parts by Incremental Forming Process”, Procedia Engineering, Vol. 97, 2014, pp. 1983-1990.

[20]  Shanmuganatan, S. P., Senthil Kumar, V. S., “Modeling of Incremental Forming Process Parameters of Al 3003 (O) by Response Surface Methodology”, Procedia Engineering, Vol. 97, 2014, pp. 346-356.

[21]  Ambrogio, G., Ingarao, G., Gaillardia, F., and Lorenzob, R. D., “Analysis of Energy Efficiency of Different Setups Able to Perform Single Point Incremental Forming (SPIF) Processes”, Procedia CIRP, Vol. 15, 2014, pp. 111-116.

[22]  Kurra, S., Prakash Regalla, S., “Experimental and Numerical Studies on Formability of Extra-Deep Drawing Steel in Incremental Sheet Metal Forming”, Materials Research and Technology, Vol. 3, No. 2, 2014, pp. 158-171.

[23]  Martínez, O., Luisa, M., Olvera, D., Bagudanch, I., and Elías, A., “Tool Dynamics During Single Point Incremental Forming Process”, Procedia Engineering, Vol. 81, 2014, pp. 2286-2291.

[24]  Devarajan, N., Sivaswamy, G., Bhattachary, R, Heck, D. P. M., and Siddiq,, A., “Complex Incremental Sheet Forming using Back Die Support on Aluminium 2024, 5083 and 7075 alloys”, Procedia Engineering, Vol. 81, 2014, pp. 2298-2304.

[25]  Zahedi, A., Mollaei, B. and Morovvati, M., “Numerical and Experimental Investigation of Single-Point Incremental Forming Process of Bilayer Sheet”, Modares Mechanical Engineering, Vol. 14, No. 14, 2015, pp. 1-8 (In Persian).