arXiv subjects

Eric Breitbarth

Publications and source records attributed to Eric Breitbarth.

9 recordsLinked to original sources

arXiv2026

Annotated digital image correlation displacement fields from fatigue crack growth experiments

We present a curated dataset of planar displacement fields from eight fatigue crack growth experiments obtained via full-field digital image correlation (DIC). The dataset covers multiple aerospace-grade aluminium alloys, specimen geometries, material orientations, and load configurations, providing a diverse experimental basis for data-driven fracture mechanics research. Crack tip locations are consistently annotated using an iterative correction procedure applied to all measurements, and fracture mechanical descriptors like stress-intensity factors are provided as additional labels. The dataset comprises 8,794 unique experimentally observed displacement fields and a total of 70,352 supervised samples generated through standardized interpolation and augmentation. DIC data is provided as uniformly interpolated displacement grids at three standardized resolutions 28 x 28, 64 x 64, and 128 x 128 pixels, each available in three dataset sizes to support scalable use cases ranging from educational applications to high-capacity model development. Accompanying metadata and a Python interface facilitate filtering, loading, and integration into reproducible machine learning and fracture mechanics workflows.

cond-mat.mtrl-sci↗

arXiv2025

Progress on Data-Driven, Multi-Objective Quantum Optimization

Here, we present two complementary approaches that advance quadratic unconstrained binary optimization (QUBO) toward practical use in data-driven materials design and other real-valued black-box optimization tasks. First, we introduce a simple yet powerful preprocessing scheme that, when applied to a machine-learned QUBO model, entirely removes system-level equality constraints by construction. This makes cumbersome soft-penalty terms obsolete, simplifies QUBO formulation, and substantially accelerates solution search. Second, we develop a multi-objective optimization strategy inspired by Tchebycheff scalarization that is compatible with non-convex objective landscapes and outperforms existing QUBO-based Pareto front methods. We demonstrate the effectiveness of both approaches using a simplified model of a multi-phase aluminum alloy design problem, highlighting significant gains in efficiency and solution quality. Together, these methods broaden the applicability of QUBO-based optimization and provide practical tools for data-driven materials discovery and beyond.

cond-mat.mtrl-sci↗

arXiv2025

Trustworthy AI-based crack-tip segmentation using domain-guided explanations

Ensuring the trustworthiness and robustness of deep learning models remains a fundamental challenge, particularly in high-stakes scientific applications. In this study, we present a framework called attention-guided training that combines explainable artificial intelligence techniques with quantitative evaluation and domain-specific priors to guide model attention. We demonstrate that domain-specific feedback on model explanations during training can enhance the model's generalization capabilities. We validate our approach on the task of semantic crack tip segmentation in digital image correlation data, which is a key application in the fracture mechanical characterization of materials. By aligning model attention with physically meaningful stress fields, such as those described by Williams' analytical solution, attention-guided training ensures that the model focuses on physically relevant regions. This finally leads to improved generalization and more faithful explanations.

cond-mat.mtrl-sci↗

arXiv2024

Advanced crack tip stress analysis using interaction integrals in high-resolution digital image correlation fields

The link between microscopic mechanisms and macroscopic behaviour, represented by the $da/dN-\Delta K$ curve, plays an increasingly important role in relating the fatigue crack growth curve required for component design to the underlying physics. High-resolution digital image correlation (HR-DIC) allows for in-depth analysis of microscopic fatigue crack growth mechanisms, but is rarely used to determine the SIF of the crack tip. This paper examines the applicability of the interaction integral in HR-DIC data and identifies factors that should be considered when evaluating the integral results. A major influence is the integration near the PZ, which leads to an erroneous increase in the calculated SIF result. In addition, the large integration path gaps required in HR-DIC around the crack path significantly hinder accurate results. The effect of the crack face contact is overall small. While it slightly increases the SIF result, it does not correlate with the crack opening load $K_\mathrm{op}$.

physics.app-ph↗

arXiv2024

Identification and characterization of three-dimensional crack propagation mechanism in the Aluminium alloy AA2024-T3 using high-resolution Digital Image Correlation

Fatigue crack growth is usually a three-dimensional problem, but it is often simplified to two dimensions to reduce complexity. However, this study investigates the relationships between microscopic effects such as crack kinking, shear lips, and plasticity that are present in reality. Therefore, crack propagation tests were carried out on 2-mm-thick MT-160 specimens of AA2024-T3 sheet material in L-T and T-L orientation. Using high-resolution digital image correlation (DIC), the plastic zone was identified and measured on the samples surface. The fracture surfaces were then digitized and their 3D shape characterized. Finite element simulations confirm the presence of a local mixed-mode I/II/III state along the crack front for a slant or double shear-fracture type. A derived mapping function enables the determination of the fracture type from the surface plastic zone, along with the current crack tip loading during the test. Finally, a transition of the fracture type also leads to a short-term delay in the crack propagation rate. Based on this information crack propagation curves are computed with regards to the local 3D crack orientation.

cond-mat.mtrl-sci↗

arXiv2024

A universal crack tip correction algorithm discovered by physical deep symbolic regression

Digital image correlation is a widely used technique in the field of experimental mechanics. In fracture mechanics, determining the precise location of the crack tip is crucial. In this paper, we introduce a universal crack tip detection algorithm based on displacement and strain fields obtained by digital image correlation. Iterative crack tip correction formulas are discovered by applying deep symbolic regression guided by physical unit constraints to a dataset of simulated cracks under mode I, II and mixed-mode conditions with variable T-stress. For the training dataset, we fit the Williams series expansion with super-singular terms to the simulated displacement fields at randomly chosen origins around the actual crack tip. We analyse the discovered formulas and apply the most promising one to digital image correlation data obtained from uniaxial and biaxial fatigue crack growth experiments of AA2024-T3 sheet material. Throughout the experiments, the crack tip positions are reliably detected leading to improved stability of the crack propagation curves.

cond-mat.mtrl-sci↗

arXiv2023

Fatigue crack growth in anisotropic aluminium sheets -- phase-field modelling and experimental validation

Fatigue crack growth is decisive for the design of thin-walled structures such as fuselage shells of air planes. The cold rolling process, used to produce the aluminium sheets this structure is made of, leads to anisotropic mechanical properties. In this contribution, we simulate the fatigue crack growth with a phase-field model due to its superior ability to model arbitrary crack paths. A fatigue variable based on the Local Strain Approach describes the progressive weakening of the crack resistance. Anisotropy regarding the fracture toughness is included through a structural tensor in the crack surface density. The model is parameterised for an aluminium AA2024-T351 sheet material. Validation with a set of experiments shows that the fitted model can reproduce key characteristics of a growing fatigue crack, including crack path direction and growth rate, considering the rolling direction.

cond-mat.mtrl-sci↗

arXiv2023

Generating artificial digital image correlation data using physics-guided adversarial networks

Digital image correlation (DIC) has become a valuable tool to monitor and evaluate mechanical experiments of cracked specimen, but the automatic detection of cracks is often difficult due to inherent noise and artefacts. Machine learning models have been extremely successful in detecting crack paths and crack tips using DIC-measured, interpolated full-field displacements as input to a convolution-based segmentation model. Still, big data is needed to train such models. However, scientific data is often scarce as experiments are expensive and time-consuming. In this work, we present a method to directly generate large amounts of artificial displacement data of cracked specimen resembling real interpolated DIC displacements. The approach is based on generative adversarial networks (GANs). During training, the discriminator receives physical domain knowledge in the form of the derived von Mises equivalent strain. We show that this physics-guided approach leads to improved results in terms of visual quality of samples, sliced Wasserstein distance, and geometry score when compared to a classical unguided GAN approach.

eess.IV↗

arXiv2023

Advanced crack tip field characterization using conjugate work integrals

The quantitative characterisation of crack tip loads is fundamental in fracture mechanics. Although the potential influence of higher order terms on crack growth and stability is known, classical studies solely rely on first order stress intensity factors. We calculate higher order Williams coefficients using an integral technique based on conjugate work integrals and study the convergence with increasing crack tip distance. We compare the integral method to the state-of-the-art fitting method and provide results for higher-order terms with several crack lengths, external forces, and sizes for widely used middle tension, single-edge cracked tension, and compact tension specimen under mode-I loading.

cond-mat.mtrl-sci↗