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This paper presents the features and functions of a software tool called Fatigue Prediction Utility for Abaqus/CAE (FPU). It is designed as a plugin for the Abaqus commercial FE code allowing for fatigue predictions based on the results of Abaqus FE analyses. It also contains an interface for data transfer between Abaqus and PragTic, a standalone fatigue post-processor. The program contains a simple and intuitive graphical interface, which makes preparation of a fatigue analysis straightforward. The FPU fatigue solver may be executed on multiple CPU cores independently from Abaqus/CAE, which allows large-scale problems to be solved on server machines in reasonable time. An overview of the functionality of the plugin, available prediction models and the concept of data exchange between Abaqus and PragTic is given. Illustrative examples are given, where appropriate, in order to introduce features of the tool. Possible ways of adapting the code for interconnection with an FE solver other than Abaqus are discussed. [ABSTRACT FROM AUTHOR]

Abstract: An advance parametric FEA model for simulation of pitting arise phenomena on the gear teeth is presented in this article. The assumption of the developed computational approach was that pitting (pits on the contact surfaces) is a result of fatigue crack propagation under (rolling) contact loading conditions. Developed crack growth laws (based on the Paris law) allow to perform simulations of pitting crack growth with respect to the non-proportional and non-linear nature of loading of pitting crack tip, which result from specific loading condition. Specific crack tip loading and pitting crack growth was evaluated using the J-integral criterion of fracture mechanics. Advance model of penetration of the fluid lubricant into fatigue (pitting) cracks was designed using special hydrostatic fluid finite elements, which allow to include the closure of pressured lubricant between fracture surfaces during the simulation of gearing meshing. A simplified distribution of residual stresses in the surface layers of teeth is included as well. The simulations were carried out under the commercial code ABAQUS CAE FEM programme which allows to develop in-house codes using the Python scripting language and user subroutines. Mentioned programme codes and user subroutines are the basis of all FEA including the simulation of the specific loading conditions of pitting crack tip and the incremental pitting crack growth. Wide sensitivity study of the influence of selected model parameters was carried out. Achieved results – final pitting crack shapes and time needed for their formation were compared with experimental results. [Copyright &y& Elsevier]

Highlights: [•] We performed uncoupled elastic–plastic - damage material calibration. [•] We used custom design specimens and testing devices to perform all experiments. [•] We calibrated fracture locus according to Bai and Wierzbicki. [•] We outlined calibration alternative based on target function variants. [•] Experiments with excessive stress concentration showed limitations of used approach. [ABSTRACT FROM AUTHOR]

Abstract: Current knowledge about the fretting phenomenon and multiaxial fatigue criteria is briefly reviewed. Experimental equipment for fretting fatigue testing at the Czech Technical University (CTU) in Prague is introduced, and the results of experiments are presented. The digital image correlation (DIC) method was employed to calibrate the friction coefficient in a numerical model. This detailed model of the fretting-fatigue experimental setup was then used for computing the stress field histories of periodically loaded specimens. This data was used as input for the multiaxial fatigue criteria, and the prediction quality of the criteria was verified. The prediction model assessment results are presented. The results indicate that the criteria are not capable of handling the different damage mechanisms, which vary with the pressure load of the contact interface. A certain correction reflecting the contact kinematic behaviour therefore needs to be introduced into their mathematical formulation. The DIC method performed well in capturing local displacements in the vicinity of the stick–slip interface, and it provided necessary data for calibrating the friction coefficient. [Copyright &y& Elsevier]