Forming limit diagram generation with reduced experiments and modelling for different grades of automotive sheet steel using CrachLab

Forming limit diagram is one of the most commonly used failure criteria for sheet metal forming analysis. Forming limit diagram generation is time-consuming, and therefore, any reduction in the test requirements will be useful for the industry. In this work, a novel method has been proposed to generate such forming limit diagram with significantly reduced experimental efforts. The proposed new method is based on a combination of fewer experiments and the use of CrachLab (developed by MATFEM), which is based on the numerical modelling of tensile instability using Marciniak–Kuczynski method or MK method. The forming limit diagram generated using the new methodology has been compared with the one obtained using the standard procedure (as per ISO 12004-2), and a good correlation has been obtained. The proposed method, which requires significantly less experimental efforts, will be very useful for industries.