Fracture Mechanics Parameters Research Articles

Sustainable future of construction: the potential of concrete with basalt mini-bars as reinforcement

The paper concerns the influence of basalt minibars on the subcritical and critical behaviour of test specimens made of concrete with low-emission cement. Low-emission cement produces lower emissions of greenhouse gases and other pollutants than traditional cement. Analyses were conducted on changes in fracture mechanics parameters depending on the content of microfibers in the concrete mix (0, 2, 4, 8 kg/m³), the type of cement used, and the water-to-cement ratio (w/c). It was demonstrated that concrete reinforced with basalt microfibers exhibits increased resistance to crack initiation and propagation. An increase in the stress intensity factor was observed for CEMI 42.5R concretes at w/c=0.5 by 27%, at w/c =0.4 by 62%, and for CEM II 42.5R/A-V concretes at w/c=0.5 by 29%, and at w/c=0.4 by as much as 30%. It was shown that the addition of microfibers to concrete made with low-emission cement significantly increases the mechanical parameters of this material.

On the Link between Plastic Wake Induced Crack Closure and the Fatigue Threshold

This purpose of this paper is to examine the relationship between crack growth equations based on Elber’s original plastic wake induced crack closure concept and the fatigue threshold as defined by the American Society for Testing and Materials (ASTM) fatigue test standard ASTM E647-15el. It is shown that, for a number of conventionally manufactured metals, the function U(R), where R is the ratio of the minimum to maximum applied remote stress, that is used to relate the stress intensity factor ΔK to the effective stress intensity factor ΔKeff is inversely proportional to the fatigue threshold ΔKth(R). This finding also results in a simple closed form equation that relates the crack opening stress intensity factor Ko(R) to ΔK, Kmax, and the fatigue threshold terms ΔKth(R) and ΔKeff,th. It is also shown that plotting da/dN as function of ΔK/ΔKth(R) would appear to have the potential to help to identify the key fracture mechanics parameters that characterise the effect of test temperature on crack growth. As such, for conventionally manufactured metals, plotting da/dN as function of ΔK/ΔKth(R) would appear to be a useful addition to the tools available to assess the fracture mechanics parameters affecting crack growth.

A threshold criterion of stress intensity range in a steel sheet

Fatigue fractures often originate and propagate from geometric discontinuities or material defects in equipment or components. The occurrence and propagation of cracks near the fatigue limit were observed in notched specimens of a steel sheet that simulated this situation, and analyzed using fracture mechanics parameters. The notch caused strain concentration, and local plastic strain arose even at low stress amplitudes. Transgranular fracture occurred, and arrested cracks were observed near the threshold stress amplitude Δσth. The threshold stress intensity range ΔKth had a good power function correlation with the effective notch length aef, but it depended on the length and did not reach a constant value. By identifying and applying the critical power exponent, we proposed a prediction model using the function ΔKthc=Yπ1/2Δσthaef1/κ, which is the critical threshold stress intensity range that has a constant value. κ is equal to 5 for the steel sheet under transverse bending. Since ΔKth c obtained using this critical exponent method does not depend on the crack length, it can be used as a material constant and a failure criterion, and can be applied as a new strength prediction model.

New approach for determining the fracture parameters by electromagnetic-mechanical coupling

This paper introduces a novel method for assessing fracture mechanics parameters such as Stress Intensity Factor (SIF), Energy Release Rate (J) and Crack Tip Opening Displacement (CTOD). An electromagnetic–mechanical coupling (EMC) approach is employed to evaluate and to measure these fracture parameters by monitoring the variation of impedance using eddy currents. This approach relies on the eddy current signal obtained from a sensor, which calculates and verifies SIF parameters along with the J-integral and CTOD through changing the sensor impedance. To ensure theoretical consistency, the magnetic field is theoretically used, formulated and verified. Additionally, a numerical simulation method employing the finite element method is used to analyze and identify cracks in structures and assess their propagation. The quantification of SIF and J-integral parameters is demonstrated using two sensors based on a differential probe. This research paper demonstrates that the proposed method is the most efficient approach for exploring and detecting cracks in materials, as well as understanding their propagation behavior.

Efficient technique for evaluation of three-dimensional elastic–plastic fracture mechanics parameters based on equivalent distributed stress concept

This study proposes an efficient technique for the evaluation of the elastic–plastic fracture mechanics (EPFM) parameters of three-dimensional (3D) cracks based on the modified crack cohesive force (CCF) model. In the current method, the 3D crack’s EPFM parameters are analyzed by applying the pseudo crack face traction (CFT) to a two-dimensional (2D) center crack in an infinite plate. This pseudo traction is called the equivalent distributed stress (EDS). The EDS to be applied on the 2D center crack is determined in a manner that reproduces the relationship between crack length and stress intensity factor (SIF) of the intended 3D crack. Once EDS is determined, EPFM parameters for 3D cracks can be obtained instantly by using the center crack’s analytical closed-form solutions. This approach can compute the 3D crack’s EPFM parameters in dramatically less computation time than 3D finite element (FE) analysis. The effectiveness of the proposed method is validated by comparing the EPFM parameters of a 3D penny-shape crack obtained from this method against the reference analytical solutions and numerical FE analysis results. The parameters determined by the present method show excellent agreement with the reference solutions.

Application of a hierarchical quadrature element method to interface crack analysis in bi-material systems

This paper presents an extension of the hierarchical quadrature element method (HQEM) with p-convergence to evaluating fracture mechanical parameters of bi-material interface cracks. The numerical implementation of HQEM in combination with the virtual crack closure method (VCCM) is comprehensively illustrated, and the formulas for calculating the strain energy release rate (SERR) are rederived. The relationship between components of SERR and the complex stress intensity factors (SIFs) is established. In addition, the effectiveness of an auxiliary parameter related to the dual energy release rates in measuring the accuracy of the present method is examined.The feasibility of applying HQEM to the interface crack problems is demonstrated by investigating the benchmark problem of an infinite bi-material plate with a central interface crack. Two loading cases are considered, including pure tensile loading and mixed tensile-shear loading. The influence of the crack tip element size Δa on the convergence characteristics and computational accuracy of fracture parameters is quantitatively investigated to provide guidance for choosing the most reasonable value of Δa. Numerical results show that even with very coarse meshes, together with a virtual crack extension consisting of only one element, HQEM yields highly accurate results for the total SERR and the complex SIFs, making it suitable for complex, large-scale interface crack problems in dissimilar media.

Comparison of fatigue crack growth behaviour in electron-beam and laser powder-bed-fusion Inconel 718

A comparative study on fatigue crack growth behaviour was made between the electron-beam powder-bed-fusion (PBF-EB) and laser powder-bed-fusion (PBF-LB) Inconel 718. The crack followed a transgranular path with a faster propagation rate for the PBF-EB Inconel 718, whereas a combination of intergranular and transgranular path was observed for the PBF-LB, and its slower rate being comparable to the wrought counterpart. The main fatigue crack in the PBF-EB Inconel 718 exhibited a sawtooth shaped path at the micro-scale, with intensive slip traces close to the crack surfaces owing to the very low work hardening rate. Based on the digital image correlation (DIC) analysis of the crack tip field, fatigue-crack sawtooth path in the PBF-EB Inconel 718 can be successfully predicted by using a strain energy density criterion, which dictates the crack growth follows the direction of minimum distance from the crack tip to elasto-plastic boundary. For the PBF-LB Inconel 718, the predominant fatigue crack was straight at low ΔK, but severe deflections occurred at the medium and high ΔK regimes. A clear correlation exists between the incipient intergranular cracks and the main crack path deflection. This suggests that once the accumulated damage in the plastic zone around the crack tip reaches the critical value, intergranular cracks can form the new front of the fatigue crack, causing the main crack path deflection. Elasto-plastic fracture mechanics parameters of rp and ΔCTOD, derived from the DIC-based crack tip field analysis, can qualitatively predict the lower crack growth rate of the PBF-LB Inconel 718.

Predicting Stress Intensity Factor for Aluminum 6062 T6 Material in L-Shaped Lower Control Arm (LCA) Design Using Extended Finite Element Analysis.

The aim of this study is to solve a practical problem encountered in the automotive industry, especially the failure of a cracked lower control arm made of al 6062 T6 material during static and crash physical tests, and to characterize the behavior of cracked parts made of aluminum materials using the fracture mechanics parameters. As a first step, we carried out a numerical study and simulation using Abaqus/CAE 2020 software and the finite element method to determine the stress concentration and load limit capacity for different car weight cases. The von Mises stress variation shows crack initiation and propagation to be in the area of the lower control arm's attachment to the vehicle platform, where stress is concentrated. These numerical results are consistent with the experimental test results found by automotive manufacturers. Also, we find that the mechanical load that can support this part is below 4900 N for good performance. In the second step, we use the results of the first section to simulate the failure of a lower control arm with a crack defect. This paper investigates the stress intensity factor KI in mode I for different lengths (L) and depths (a) of the crack in the lower control arm using the extended finite element method (XFEM) under Abaqus/CAE. For crack failure initiation and progression, we relied on the traction separation law, specifically the maximum principal stress (MAXPS) criterion. The KI factor was evaluated for the materials steel and Al 6062 T6. The results obtained from the variation of the KI coefficient as a function of crack depth (a) and the thickness (t) show that the crack remains stable even when a depth ratio (a/t = 0.8) is reached for the steel material. However, the crack in the Aluminum 6062 T6 material becomes unstable at depth (a/t = 0.6), with a high risk of total failure of the lower control arm.

Quantifying 3D crack propagation in nodular graphite cast iron using advanced digital volume correlation and X-ray computed tomography

Advanced digital volume correlation (DVC) combined with X-ray computed tomography (XCT) was utilized to investigate the 3D crack propagation in nodular graphite cast iron under tensile loading. The objective of this work was to quantify crack growth at the voxel-scale and extract fracture mechanics parameters such as the 3D crack front, crack opening displacements (CODs), and stress intensity factors (SIFs). By employing a crack growth updating strategy and an adaptive multiscale mesh, the 3D crack shape and propagation were accurately captured throughout the entire process. Von Mises strain and COD fields were characterized to provide insights into plastic zones and variations in crack opening behavior. Estimation of SIFs revealed a mode I dominant regime and limited influence from modes II and III. This study provides comprehensive insights into crack propagation and crack opening behavior, providing valuable information to fracture mechanics.

Experimental determination of fracture mechanical properties of cement-fibre boards reinforced with cellulose and PVA fibres for FE analysis

The paper deals with determination and classification of the mechanical parameters of cement fibre boards (CFB) with cellulose and PVA reinforcing fibres. The cement fibre material with reinforcing fibres is produced using the Hatschek process, where the fibres are arranged in the production direction and the curing is subsequently verified. Test experimental samples, specimens are created from the same production batch, and are produced orienting all of them in the production direction to determine the characteristic for an orthotropic material. The fracture mechanical parameters such as fracture energy and work of fracture were then determined and verified as well. Records will be made for the determined crack mouth opening displacement (CMOD) and displacement (d) of test specimens. The loading directions are given to cover the determination of the mechanical parameters of the material. These measurements are intended to complement the mathematical model that uses FEA modelling for subsequent implementation of the material into civil engineering structures or details.

Examination of cryogenic durability in self-consolidating concretes through mechanical and fracture mechanics approaches

Thermal shocks under extreme conditions, such as leakage in concrete-enclosed tanks, which are a popular choice for cryogenic liquid storage, may lead to undesirable effects on the structures. In this study, the effects of cyclic cryogenic exposures have been investigated using both mechanical and fracture mechanics approaches. To ensure durable concrete, self-consolidating concretes have been chosen in the mix design. While previous studies have primarily investigated the effects of a single cryogenic exposure on conventional concrete, this study focuses on repetitive exposure to cryogenic effects on self-consolidating concretes. Furthermore, the self-consolidating concretes were subjected to two different curing conditions: air curing and water curing, before cryogenic processing, in order to consider real application conditions and laboratory circumstances. After the first and fifth cryogenic exposures, fundamental engineering properties and fracture mechanics parameters were evaluated. To determine the fracture mechanics parameters, beams of three different dimensions were produced, with three different notch lengths for each dimension. The dynamic modulus of elasticity, ultrasonic pulse velocity, compressive strength, and bending strength of self-consolidating concretes were examined after 0, 1, and 5 cycles of cryogenic exposure. As a result, the air-cured samples exhibited greater resistance to cryogenic cycles than the water-cured samples. The KIC and CTODC values increased after one cycle of cryogenic exposure, as noted in the literature. However, the results obtained in this study demonstrate a decrease in KIC and CTODC values after five cycles compared to one cycle of cryogenic exposure.

Comparing linear damage hypothesis to linear elastic fracture mechanics in the estimation of fatigue life in a high speed light craft

Linear elastic fracture mechanics methods provide a more comprehensive representation of crack propagation compared to traditional methods such as the linear damage hypothesis (or SN curve approach). These techniques have been widely adopted in the aerospace industry, however, their usage in the design of marine structures remains limited. The presented research uses full-scale trial data measured onboard a 111 m wave-piercing catamaran to compare the results obtained from linear elastic fracture mechanics and SN curve-based methods. The results reveal significant differences in estimated fatigue life between SN curve-based methods and fracture mechanics methods. These differences are likely due to limitations in the fracture mechanics model during the crack initiation phase. Changes in fracture mechanics parameters also had a significant effect on fatigue life, suggesting that if accuracy is important then material specific parameters are required. Despite the limitations shown, linear elastic fracture mechanics methods have a higher level of tailor-ability when compared to SN curve based methods and could offer benefits in situations such as the tracking of known flaws or in the assessment of changes to vessel configuration, or usage profiles.

Study of fatigue fracture characteristics for duplex stainless steel STHE welded joint specimen

A shell and tube heat exchanger (STHE) welded joint is considered for fatigue fracture mechanism. The joint is made up of a protruding tube fabricated to a tubesheet by means of welding. A super duplex stainless steel (DSS) material is used for the tube and tubesheet. Fatigue test was newly conducted using the single tube test specimen. The initial cracking plane was moved from the minimum sectional-area plane that was perpendicular to the loading direction, and the crack growth was almost planar. Stress analysis is carried out using finite element method (FEM) and the stress distributions are carefully studied by comparing the simple perforated plate. In addition, three-dimensional crack propagation (CP) simulation is performed employing extended finite element method (X-FEM). Fracture phenomenon is verified using the experimental and numerical crack front geometries. The fracture mechanics parameter is evaluated and verified with empirical formulae. CP behaviors are carefully discussed based on the fracture mechanics parameter. The CP life is presented for three loading amplitudes. The FAT class of the STHE welded joint is studied based on the available design standards such as BS, IIW and JSSC. Finally, the fatigue fracture characteristics of the STHE welded joint specimen are shown through the experimental and numerical methods.

Stress Intensity Factors for Pressurized Pipes with an Internal Crack: The Prediction Model Based on an Artificial Neural Network

During pipeline operation, internal cracks may occur. The severity around the crack tip can be quantified by the stress intensity factor (KI), which is a linear–elastic fracture mechanics parameter. For pressurized pipes featuring infinitely long internal surface cracks, KI can be interpolated from a function considering pressure, geometry, and crack size, as presented in API 579-1/ASME FFS-1. To enhance KI prediction accuracy, an artificial neural network (ANN) model was developed for such pressurized pipes. Predictions from the ANN model and API 579-1/ASME FFS-1 were compared with precise finite element analysis (FEA). The ANN model with an eight-neuron sub-layer outperformed others, displaying the lowest mean squared error (MSE) and minimal validation discrepancies. Nonlinear validation data improved both MSE and testing performance compared to uniform validation. The ANN model accurately predicted normalized KI, with differences of 2.2% or lower when compared to FEA results. Conversely, API 579-1/ASME FFS-1′s bilinear interpolation predicted inaccurately, exhibiting disparities of up to 4.3% within the linear zone and 24% within the nonlinearity zone. Additionally, the ANN model effectively forecasted the critical crack size (aC), differing by 0.59% from FEA, while API 579-1/ASME FFS-1′s bilinear interpolation underestimated aC by 4.13%. In summary, the developed ANN model offers accurate forecasts of normalized KI and critical crack size for pressurized pipes, providing valuable insights for structural assessments in critical engineering applications.

B-Spline Surface-Based Reduced-Order Modeling of Nonplanar Crack Growth in Structural Digital Twins

Nonplanar crack growth holds a critical role in aeronautical structures, necessitating effective analysis under mixed fatigue loading to assess structural integrity. This study introduces a reduced-order modeling (ROM) method for predicting nonplanar crack growth in structural digital twins. The method’s advantage lies in its representation of the entire crack surface morphology using a B-spline surface, which better captures its impact on crack growth. The symmetric Galerkin boundary element method–finite element method coupling method is adopted as a full-order method to generate the crack database. Isoparametric coordinates of the crack surface and stress intensity factor serve as input and output, respectively, for training the ROM, which integrates -means clustering, principal component analysis, and Gaussian process regression. The proposed approach is demonstrated using a rotorcraft-mast-like component. Results reveal superior fracture mechanics parameter prediction compared to the crack-front-based ROM. Furthermore, the method boasts three orders of magnitude greater efficiency than full-order simulation, enabling its coupling with approaches like Monte Carlo for probabilistic crack growth analysis. Future work entails integrating our method into the probabilistic framework of digital twins.

Analytical computation of stress intensity factor for active material particles of lithium ion batteries

The stress intensity factor is a widely used parameter in linear elastic fracture mechanics to assess the stress field near the crack tip, and it is usually defined as the product between the remote stress, the square root of the crack length, and a geometric factor depending on the geometry of the test specimen, the size and location of the crack. However, this well-established expression cannot be used in case of non-constant stress distribution on crack surfaces, typically resulting from diffusive field. This work presents an analytical procedure to compute the stress intensity factor due to any kind of stress distribution that can be expressed as a polynomial. Firstly, the non-constant stress distribution is expressed as a polynomial. Then, the stress intensity factor is computed according to the principle of superposition of effects, as the sum of the stress components of each single polynomial grade and the corresponding geometric factors. The geometric factors for sphere with central and superficial cracks are determined using a finite element model, and closed-form expressions for these geometric factors are provided as functions of a normalized geometric parameter. These functions can be used in case of any stress loading and spherical geometry. The analytical procedure is specifically applied to assess the stress intensity factor caused by stress resulting from lithium diffusion in active material particles of lithium ions batteries electrodes. The results are compared with those obtained using a multiphysics finite element fracture model, showing good agreement and demonstrating the accuracy of the proposed analytical procedure. Then, the procedure presented in this work enables avoiding expensive multiphysics simulations and can be used to develop fast, accurate, and computationally efficient lithium ion batteries degradation models for the online estimation of the capacity decay with charge/discharge cycles.

Fracture parameters analysis of compact tension specimens with deflected fatigue cracks: ZK60 magnesium alloy

Precise monitoring of crack growth and a comprehensive understanding of crack propagation rate are crucial for the evaluation of the structural integrity of magnesium alloys with defects. Different crack deflections caused by the coupling of specimen orientations and crack sizes significantly increase the challenge to magnesium alloy evaluation. In this paper, the systematic finite element analysis was conducted for compact tension (CT) specimens with deflection cracks. A wide range of geometric variations including initial crack length, crack deflection angle and crack propagation length were analyzed. Complete solutions of the stress intensity factor (KI and KII), T-stress and the compliance at the load line were determined. The results showed that the geometric sizes have a significant coupling effect on the fracture mechanics parameters, and the non-deflected cracked formula recommended by the ASTM standard is not applicable to the deflection crack specimens. Then, a prediction method of kinked fatigue crack length of CT specimen based on the compliance multiplier method was proposed. To further verify the importance of the fracture parameters obtained, CT fatigue crack growth (FCG) tests of ZK60 magnesium (Mg) alloy under different orientations and initial crack sizes were carried out. The FCG rate curves of ZK60 Mg alloy under different crack growth driving forces were compared and illustrated. The developed compliance multiplication method can accurately predict the real-time crack propagation length.

Selective laser sintered Pipe Ring Notched Tension specimens for examination of fracture properties of pipeline materials

In order to develop a non-standard method for determining the resistance to fracture and damage of pipeline materials, a new geometry of ring-shaped specimens with sharp notches or cracks has been defined. The need to develop a new method for testing of the specimens cut from the pipes arises due to the difficulties in determination of fracture mechanics parameters on thin-walled pressure pipelines, especially those with a smaller cross-section, by application of the standard procedures/specimens. Previous studies dealing with the topic of pipeline testing by non-standard methods are presented in the introductory part of the paper. In the experimental part of the research, tests on PRNT (Pipe Ring Notched Tension) and SENT (Single Edge Notched Tension) specimens are performed. Samples of these specimens were produced by SLS (Selective Laser Sintering) technique of additive production from PA12 (polyamide PA 2200) material. For the purpose of this study, a tool that is protected at the national level (in Serbia) as intellectual property is used for testing of the ring-shaped PRNT specimens. Tensile testing of both types of specimens is monitored by Aramis GOM 2M system; its operation is based on the method of digital image correlation, DIC. Additionally, finite element analyses are conducted on the PRNT and SENT geometries, enabling the calculation of the fracture mechanics parameter – Stress intensity factor K. It is concluded that the presented procedure based on the PRNT specimen has a good potential for use as a non-standard method for fracture resistance examination of pipeline materials. It can be performed on the specimens cut directly from the pipes (new or from exploitation). The dependence of the fracture resistance on the stress concentrator size is not pronounced, which means that the results depend dominantly on the material properties, rather than on geometry.

Multi-Layer Fabric Composites Combined with Non-Newtonian Shear Thickening in Ballistic Protection-Hybrid Numerical Methods and Ballistic Tests.

Multi-layer fabrics are commonly used in ballistics shields with a lower bulletproof class to protect against pistol and revolver bullets. In order to additionally limit the dynamic deflection of the samples, layers reinforced with additional materials, including non-Newtonian fluids compacted by shear, are additionally used. Performing a wide range of tests in each case can be very problematic; therefore, there are many calculation methods that allow, with better or worse results, mapping of the behavior of the material in the case of impact loads. The search for simplified methods is very important in order to simplify the complexity of numerical fabric models while maintaining the accuracy of the results obtained. In this article, multi-layer composites were tested. Two samples were included in the elements subjected to shelling. In the first sample, the outer layers consisted of aramid fabrics in a laminate with a thermoplastic polymer matrix. The middle layer contained a non-Newtonian shear-thickening fluid enclosed in hexagonal (honeycomb) cells. The fluid was produced using polypropylene glycol and colloidal silica powder with a diameter of 14 µm in the proportions of 60/40. The backing plate was made using a 12-layer composite made of Twaron® para-aramid fabrics with a DCPD matrix-not yet used in a wide range of ballistics. Then, numerical simulations were carried out in the Abaqus/Explicit dynamic analysis. The Johnson-Cook constitutive strength model was used to describe the behavior of elastic-plastic materials constituting the elements of the projectiles. For the non-Newtonian fluid, a Up-Us EOS was used. The inner layers of the fabric were treated as an orthotropic material. Complete homogenization of the sample layers was carried out, thanks to which each layer was treated as a homogeneous continuum. As a parameter of fracture mechanics for shield components, the strain criterion was used with the smooth particles hydrodynamics method (SPH). Then, the results of simulations were compared with the results of the ballistic test for both samples placed next to each other, which resulted in the formation of a multi-layer composite in one ballistic test subjected to impact loads during firing with a 9 × 19 mm Parabellum FMJ projectile with an initial velocity of 370 ± 10 m/s. The results of numerical tests are very similar to the ballistic tests, which indicates the correct mapping of the process and the correct conduct of layer homogenization. The applied proportions of the components in the non-Newtonian fluid allowed a reduction in the deflection compared to previous studies. Additionally, the proposal to use a DCPD matrix allowed to obtain a much lower deflection value compared to other materials, which is a novelty in the field of production of ballistic shields.

ProCrackPlast: a finite element tool to simulate 3D fatigue crack growth under large plastic deformations

Many structural components and devices in combustion and automotive engineering undergo highly intensive cyclic thermal and mechanical loading during their operation, which leads to low cycle (LCF) or thermomechanical (TMF) fatigue crack growth. This behavior is often characterized by large scale plastic deformations and creep around the crack, so that concepts of linear-elastic fracture mechanics fail. The finite element software ProCrackPlast has been developed at TU Bergakademie Freiberg for the automated simulation of fatigue crack growth in arbitrarily loaded three-dimensional components with large scale plastic deformations, in particular under cyclic thermomechanical loading. ProCrackPlast consists of a bundle of Python routines, which manage finite element pre-processing, crack analysis, and post-processing in combination with the commercial software Abaqus . ProCrackPlast is based on a crack growth procedure which adaptively updates the crack size in finite increments. Crack growth is controlled by the cyclic crack tip opening displacement varDelta CTOD, which is considered as the appropriate fracture-mechanical parameter in case of large scale yielding. The three-dimensional varDelta CTOD concept and its effective numerical calculation by means of special crack-tip elements are introduced at first. Next, the program structure, the underlying numerical algorithms and calculation schemes of ProCrackPlast are outlined in detail, which capture the plastic deformation history along with the moving crack. In all simulations, a viscoplastic cyclic material law is used within a large strain setting. The numerical performance of this software is studied for a single edge notch tension (SENT) specimen under isothermal cyclic loading and compared to common finite element techniques for fatigue crack simulation. The capability of this software is featured in two application examples showing crack growth under mixed-mode LCF and TMF in a typical austenite cast steel, Ni-Resist. In combination with a crack growth law identified in terms of varDelta CTOD for a specific material, the tool ProCrackPlast is able to predict the crack evolution in a 3D component for a given thermomechanical loading scenario.