BM2 : Fracture Model Prediction of Nonlinear Forming Processes
This benchmark challenge consists of a set of 20 experimental strain paths extended beyond the point of fracture that are obtained from nonlinear tests on DP 1180 and AA 6xxx-T81. The extension is done using an algorithm that mimics the strain measurement error of the experimental data to avoid hints about when fracture occurred in each test. Participants are challenged to analyze these strain paths defined in terms of the strain tensor components in a coordinate system aligned to the RD of the sheet coil as they would analyze the same strain paths predicted in a finite element simulation to predict when fracture occurred, and if localized necking preceded the fracture, predict the strain at the onset of necking. The material characterization data provided in the download are sufficient to calibrate most constitutive models, and most localized necking and fracture models under conditions near to linear loading. In addition, one set of bilinear fracture calibration data is made available to enable calibration of nonlinear damage accumulation model to predict fracture under severely nonlinear loading conditions, as is present in most of the 20 strain paths in the benchmark challenge.
Download BM2 Benchmark Files