In this work, a material model is presented that predicts the crash-relevant constitutive behavior of quench-hardenable boron steel 22MnB5 as function of material hardness. Three sets of sheets of 22MnB5 are heat treated such that their as-treated microstructures are close to fully martensitic, bainitic and ferritic/pearlitic, respectively. Hardness measurements show that the resulting blanks cover the full scope of possible hardness values, from 165 HV in the ferritic/pearlitic range to 477 HV in the fully hardened state. These three main grades provide the input data for a constitutive model consisting of an extended Swift hardening law and a strain-based fracture criterion. The hardening behavior of each grade is determined using standard tensile tests. For calibration of the fracture criterion, four different fracture samples are used. The developed model predicts the behavior of intermediate hardness grades by piecewise linear interpolation between the hardening and fracture models of the three calibrated grades. A newly developed tapered tensile test specimen is used to validate the model at hand.
|Title of host publication||Forming Technology Forum|
|Place of Publication||Herrsching|
|Number of pages||6|
|Publication status||Published - 19 Sep 2013|
|Event||6th Forming Technology Forum 2013: Modelling of process chains and interfaces for sheet metal forming - Haus der bayerischen Landwirtschaft, Herrsching, Germany|
Duration: 19 Sep 2013 → 20 Sep 2013
|Conference||6th Forming Technology Forum 2013|
|Period||19/09/13 → 20/09/13|
Eller, T. K., Greve, L., Anders, M. T., Medricky, M., Hatscher, A., Meinders, T., & van den Boogaard, T. (2013). Constitutive modeling of quench-hardenable boron steel with tailored properties. In W. Volk (Ed.), Forming Technology Forum (pp. 1-6). Herrsching.