Calibration of Advanced Yield Criteria Using Uniaxial and Heterogeneous Tensile Test Data

Abstract

Conventionally, plastic anisotropy is calibrated by using standard uniaxial tensile and biaxial test results. Alternatively, heterogeneous strain field specimens in combination with full-field measurements can be used for this purpose. As reported by the literature, such an approach reduces the number of required tests enormously, but it is challenging to obtain reliable results. This paper presents an alternative methodology, which represents a compromise between the conventional and heterogeneous strain field calibration technique. The idea of the method is to use simple tests, which can be conducted on the uniaxial testing machine, and to avoid the use of advanced measuring equipment. The procedure is accomplished by conducting standard tensile tests, which are simple and reliable, and by a novel heterogeneous strain field tensile test, to calibrate the biaxial stress state. Moreover, only two of the parameters required for full characterisation need to be inversely identified from the test response; the other parameters are directly determined from the uniaxial tensile test results. This way, a dimension of optimization space is reduced substantially, which increases the robustness and effectiveness of the optimization algorithm.

Flat Specimen Shape Recognition Based on Full-Field Optical Measurements and Registration Using Mapping Error Minimization Method

“…More specifically, the method deals with the alignment of planar specimens, which is a field becoming increasingly popular due to its potential when combining full-field measurements with material characterization. As presented in [22], by using the full-field measurement techniques and monitoring the specimen loads, it is possible to characterize the anisotropic material behaviour from a single heterogeneous strain field specimen by employing inverse identification techniques (eq. finite element model updating, virtual fields method).…”

“…Practical application of the method is demonstrated on a specimen presented in [22] (Fig. 7), designed to induce a biaxial strain-stress state.…”

“…The calibration procedure was performed using a special two-sided calibration target. The purpose of such a set-up is enhanced characterization of material mechanical behaviour [22]. The DIC method was carried out with Istra 4D software.…”

Identification of Anisotropic Yield Functions Using FEMU and an Information-Rich Tensile Specimen

“…An identification strategy that enables to mitigate the effect of parameter interaction is currently investigated and will be published in a forthcoming paper. Finally, it must be noted that the problem can be solved if a complex tensile-load specimen is also used to add biaxial tension, as proposed by Macek et al [23].…”

Prediction of Strain Limits via the Marciniak-Kuczynski Model and a Novel Semi-Empirical Forming Limit Diagram Model for Dual-Phase DP600 Advanced High Strength Steel

“…on error minimization by referring to experimental yield strengths (σ 0 , σ 45 , σ 90 , σ b ) and anisotropy coefficients (r 0 , r 45 , r 90 , r b ) are applied to determine them. This method was explained in detail in[36]. To determine the YLD2000-2d yield function model's parameters, theoretical calculation of anisotropies and yield stresses, at different orientation angles were used.…”