scholarly journals Residual Stress Distribution Design for Gear Surfaces Based on Genetic Algorithm Optimization

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 366
Author(s):  
Zhou Chen ◽  
Yibo Jiang ◽  
Zheming Tong ◽  
Shuiguang Tong

The rolling contact fatigue of gear surfaces in a heavy loader gearbox is investigated under various working conditions using the critical plane-based multiaxial Fatemi–Socie criterion. The mechanism for residual stress to increase the fatigue initiation life is that the compressive residual stress has a negative normal component on the critical plane. Based on this mechanism, the genetic algorithm is used to search the optimum residual stress distribution that can maximize the fatigue initiation life for a wide range of working conditions. The optimum residual stress distribution is more effective in increasing the fatigue initiation life when the friction coefficient is larger than its critical value, above which the fatigue initiation moves from the subsurface to the surface. Finally, the effect on the fatigue initiation life when the residual stress distribution deviates from the optimum distribution is analyzed. A sound physical explanation for this effect is provided. This yields a useful guideline to design the residual stress distribution.

Author(s):  
Tomasz Brynk ◽  
Agnieszka Teresa Krawczyńska ◽  
Daria Setman ◽  
Zbigniew Pakieła

Abstract A method has been developed for determining residual stress based on displacement fields near drilled holes analyzed using 3D digital image correlation. Finite element modeling was used to determine corrections for analytical equations describing displacement fields near the blind holes, which made it possible to determine the residual stress distribution over a wide range of hole depth-to-hole diameter ratios and various areas of displacement field measurements using inverse method iterative calculations. The proposed method eliminates many drawbacks of traditional procedure based on strain gauges as hole eccentricity sensitivity and requirement of the relatively large span between holes. The method and testing setup, build-up of generally available components, were used to determine the residual stress distribution for 316 LVM samples processed by two methods from the large deformation group: hydrostatic extrusion (HE) and high-pressure torsion (HPT), by drilling 1.75 and 0.58-mm-diameter blind holes, respectively. In the case of the measurements performed on the surface of a HE-processed 16 mm bar cut along its diameter, a gradual change was revealed—from a compressive to a tensile residual stress distribution (from ~ − 300 MPa in the center to 400 MPa in 4 mm distance from the edge) in the longitudinal direction, with near-zero values in the radial direction. Moreover, the method was also adapted to perform measurements on the outside surface of the bar, which gave results consistent with those taken along the radius profile (~ 600 MPa longitudinal stress). Measurements on the top surface of a cylinder 10 mm in diameter and 1 mm high processed by HPT showed a high compressive residual stress in the center and a dominant shear component for the holes drilled at different distances from the center.


2018 ◽  
Vol 140 (6) ◽  
Author(s):  
Wei Wang ◽  
Huaiju Liu ◽  
Caichao Zhu ◽  
Philippe Bocher ◽  
Heli Liu ◽  
...  

Carburized gears are applied extensively in large-scale heavy duty machines such as wind turbines. The carburizing and quenching processes not only introduce variations of hardness from the case to the core but also generate a residual stress distribution, both of which affect the rolling contact fatigue (RCF) during repeated gear meshing. The influence of residual stress distribution on the RCF risk of a carburized wind turbine gear is investigated in the present work. The concept of RCF failure risk is defined by combining the local material strength and the multi-axial stress condition resulting from the contact. The Dang Van multi-axial fatigue criterion is applied. The applied stress field is calculated through an elastic-plastic contact finite element model. Residual stress distribution and the hardness profile are measured and compared with existed empirical formula. Based upon the Pavlina–Tyne relationship between the hardness and the yield strength, the gradient of the local material strength is considered in the calculation of the RCF failure risk. Effects of the initial residual stress peak value and its corresponding depth position are studied. Numerical results reveal that compressive residual stress (CRS) is beneficial to RCF fatigue life while tensile residual stress (TRS) increases the RCF failure risk. Under heavy load conditions where plasticity occurs, the accumulation of the plastic strain within the substrate is significantly affected by the initial residual stress distribution.


2007 ◽  
Vol 345-346 ◽  
pp. 1469-1472
Author(s):  
Gab Chul Jang ◽  
Kyong Ho Chang ◽  
Chin Hyung Lee

During manufacturing the welded joint of steel structures, residual stress is produced and weld metal is used inevitably. And residual stress and weld metal influence on the static and dynamic mechanical behavior of steel structures. Therefore, to predict the mechanical behavior of steel pile with a welded joint during static and dynamic deformation, the research on the influence of the welded joints on the static and dynamic behavior of steel pile is clarified. In this paper, the residual stress distribution in a welded joint of steel piles was investigated by using three-dimensional welding analysis. The static and dynamic mechanical behavior of steel piles with a welded joint is investigated by three-dimensional elastic-plastic finite element analysis using a proposed dynamic hysteresis model. Numerical analyses of the steel pile with a welded joint were compared to that without a welded joint with respect to load carrying capacity and residual stress distribution. The influence of the welded joint on the mechanical behavior of steel piles during static and dynamic deformation was clarified by comparing analytical results


Author(s):  
A.G. Ramu ◽  
Sunwoo Kim ◽  
Heungwoo Jeon ◽  
Amal M. Al-Mohaimeed ◽  
Wedad A. Al-onazi ◽  
...  

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