scholarly journals Machine Learning-Based Prediction and Optimisation System for Laser Shock Peening

2021 ◽  
Vol 11 (7) ◽  
pp. 2888
Author(s):  
Jino Mathew ◽  
Rohit Kshirsagar ◽  
Suraiya Zabeen ◽  
Niall Smyth ◽  
Stratis Kanarachos ◽  
...  
Keyword(s):  
Machine Learning ◽  
Residual Stress ◽  
Residual Stresses ◽  
Process Parameters ◽  
Intelligent System ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Laser Shock ◽  
Process Variables ◽  
Shock Peening

Laser shock peening (LSP) as a surface treatment technique can improve the fatigue life and corrosion resistance of metallic materials by introducing significant compressive residual stresses near the surface. However, LSP-induced residual stresses are known to be dependent on a multitude of factors, such as laser process variables (spot size, pulse width and energy), component geometry, material properties and the peening sequence. In this study, an intelligent system based on machine learning was developed that can predict the residual stress distribution induced by LSP. The system can also be applied to “reverse-optimise” the process parameters. The prediction system was developed using residual stress data derived from incremental hole drilling. We used artificial neural networks (ANNs) within a Bayesian framework to develop a robust prediction model validated using a comprehensive set of case studies. We also studied the relative importance of the LSP process parameters using Garson’s algorithm and parametric studies to understand the response of the residual stresses in laser peening systems as a function of different process variables. Furthermore, this study critically evaluates the developed machine learning models while demonstrating the potential benefits of implementing an intelligent system in prediction and optimisation strategies of the laser shock peening process.

Experimental and Numerical Analysis of the Distribution of Residual Stresses Induced by Laser Shock Peening in a 2050-T8 Aluminium Alloy

2011 ◽  
Vol 681 ◽  
pp. 296-302 ◽  
Author(s):  
Neila Hfaiedh ◽  
P. Peyre ◽  
I. Popa ◽  
Vincent Vignal ◽  
Wilfrid Seiler ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Aluminium Alloy ◽  
Residual Stress Distribution ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Laser Shock ◽  
X Ray Diffraction ◽  
Shock Peening

Laser shock peening (LSP) is an innovative surface treatment technique successfully applied to improving fatigue performance of metallic material. The specific characteristic of (LSP) is the generation of a low work-hardening and a deep compressive residual stresses mechanically produced by a laser-induced shock wave propagating in the material. The aim of this study is to analyse the residual stress distribution induced by laser peening in 2050-T8 aluminium alloy experimentally by the X-ray diffraction technique (method sin2Y) and numerically, by a finite element numerical modelling. A specific focus was put on the residual stress distribution along the surface of the impacted material.

Finite Element Analysis of the Effect of Overlapping Impacts of Laser Shock Peening Within Annealed AISI 1053 Steel

2010 ◽  
Author(s):  
Rohit Voothaluru ◽  
C. Richard Liu
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Residual Stresses ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Laser Shock ◽  
Fatigue Wear ◽  
Short Period ◽  
Shock Peening ◽  
Compressive Residual Stresses

Laser shock peening is a surface treatment technique similar to conventional shot peening. The laser induced plasma causes plastic deformations and compressive residual stresses in materials which are useful for developing improved properties in the fields of fatigue, wear or stress corrosion cracking. Finite element method is an efficient tool to predict the mechanical effects and the deformations caused due to laser shock peening, which otherwise are difficult to calculate due to the severe pressure imparted in a very short period of time. This paper presents the calculations performed using ABAQUS, for the simulation of multiple laser shock processing in order to evaluate the residual stress and the deformation of the material. A study of the effect of multiple laser shocks and their extent of overlap on the affected depths and the tensile and compressive residual stresses has been discussed. FEM calculations of residual stress fields and extent of surface deformation in annealed AISI 1053 steel has been investigated along with a study of the distribution of tensile and compressive residual stresses due to the difference in the extent of overlap of the multiple shocks.

Finite Element Analysis of the Variation in Residual Stress Distribution in Laser Shock Peening of Steels

2012 ◽  
Vol 134 (6) ◽  
Author(s):  
Rohit Voothaluru ◽  
C. Richard Liu ◽  
Gary J. Cheng
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Residual Stresses ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Stress Distributions ◽  
Laser Shock ◽  
Shock Peening ◽  
The Impact ◽  
Compressive Residual Stresses

Laser shock peening (LSP) is a surface treatment technique similar to conventional shot peening. The laser induced plasma causes plastic deformations and compressive residual stresses that are useful for developing improved properties in the fields of resistance to fatigue, wear or stress corrosion cracking. The actual distribution of residual stresses is extremely important while designing for improved fatigue life using laser shock peening, as fatigue cracks would initiate from the weakest point in the structure. In this paper, the variations in distribution of residual stresses due to laser shock peening are studied with a focus on two materials, annealed 1053 and hardened 52100 AISI steels. A 3D finite element model was developed to study the actual distributions of the residual stresses due to laser shock peening. The effect of hardness on the distribution of the residual stresses and the presence of tensile residual stresses in the surrounding regions of the impact is analyzed. Much larger variations in the residual stress distributions were observed in case of the 1053 steel as compared to hardened 52100 steel. A comprehensive analysis of the simulation results was performed in order to address and explain this behavior. It was observed that the extent of overlap would also affect the variations in the residual stress distributions. The tensile residual stresses present in the areas surrounding the shocked region were also analyzed based upon the extent of overlap and the hardness of the material. It was observed that the ratio of peak tensile to compressive residual stresses developed in 1053 steel was much higher as compared to that in the hardened 52100 steel.

scholarly journals An Approach to Predict the Residual Stress-Depth-Profile of Thin Sheet Metal Processed by Laser Shock Peening Without Coating

2021 ◽  
Vol 1135 (1) ◽  
pp. 012025
Author(s):  
Tobias Valentino ◽  
Andreas Stephen ◽  
Tim Radel
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Depth Profile ◽  
Thin Sheet ◽  
Laser Shock Peening ◽  
Stress Profile ◽  
Thin Sheets ◽  
Laser Shock ◽  
Process Step ◽  
Shock Peening

Abstract For conventional laser shock peening, the positive influence of compressive residual stresses on fatigue strength is well understood. To protect the material’s surface from ablation, a sacrificial layer is applied. This, however, leads to an additional process step, which deteriorates its economic efficiency. Thus, laser shock peening without coating (LPwC) is more frequently investigated for industrial applications. However, LPwC increases the thermal impact on the material, which may provoke tensile residual stresses in the surface region. In this regard, understanding the influence of LPwC on the residual stress state and deriving a suitable state, e.g., for subsequent applications or forming operations, result in a design of experiment with numerous residual stress measurements. Residual stress-depth-profiles obtained by X-ray diffraction are time-consuming and cost intensive. Hence, a model is proposed to predict the residual stress-depth-profile of LPwC-processed thin sheets. The analytical model is based on the source stress model and uses experimental results, namely hardness as well as shape change measurements. Sheets made of X5CrNi18-10 and with a thickness of 1 mm are LPwC-processed with a nanosecond fiber laser. In the thermally dominated area where tensile residual stresses are present, the model agrees well with the experimental measurements. Moreover, it is revealed that LPwC leads to a saturation of residual stress level maximum and depth in dependence of pulse energy, repetition rate and number of repetitions. Subsequently, the model is used for tailoring the stress profile of thin sheets by LPwC for subsequent bottom bending.

scholarly journals A parametric neutron Bragg edge imaging study of additively manufactured samples treated by laser shock peening

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Matteo Busi ◽  
Nikola Kalentics ◽  
Manuel Morgano ◽  
Seth Griffiths ◽  
Anton S. Tremsin ◽  
...  
Keyword(s):  
Residual Stress ◽  
Additive Manufacturing ◽  
Residual Stresses ◽  
Compressive Residual Stress ◽  
Laser Shock Peening ◽  
Powder Bed Fusion ◽  
Laser Shock ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Shock Peening

AbstractLaser powder bed fusion is an additive manufacturing technique extensively used for the production of metallic components. Despite this process has reached a status at which parts are produced with mechanical properties comparable to those from conventional production, it is still prone to introduce detrimental tensile residual stresses towards the surfaces along the building direction, implying negative consequences on fatigue life and resistance to crack formations. Laser shock peening (LSP) is a promising method adopted to compensate tensile residual stresses and to introduce beneficial compressive residual stress on the treated surfaces. Using neutron Bragg edge imaging, we perform a parametric study of LSP applied to 316L steel samples produced by laser powder bed fusion additive manufacturing. We include in the study the novel 3D-LSP technique, where samples are LSP treated also during the building process, at intermediate build layers. The LSP energy and spot overlap were set to either 1.0 or 1.5 J and 40$$\%$$ % or 80$$\%$$ % respectively. The results support the use of 3D-LSP treatment with the higher LSP laser energy and overlap applied, which showed a relative increase of surface compressive residual stress (CRS) and CRS depth by 54$$\%$$ % and 104$$\%$$ % respectively, compared to the conventional LSP treatment.

Application of the Eigenstrain Theory to Predict Residual Stress around Curved Edges after Laser Shock Peening

2013 ◽  
Vol 768-769 ◽  
pp. 185-192 ◽  
Author(s):  
Stefano Coratella ◽  
M. Burak Toparli ◽  
Michael E. Fitzpatrick
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Laser Shock Peening ◽  
Stress Profile ◽  
Laser Shock ◽  
Element Analysis ◽  
Residual Stress Profile ◽  
The Finite Element Analysis ◽  
Treatment Technologies ◽  
Shock Peening

Residual stresses play a fundamental role in mechanical engineering. They can be generated by manufacturing processes or introduced purposely by surface treatment technologies. One of the most recent technologies developed to introduce residual stresses is Laser Shock Peening. Since it is a relatively expensive technology, a fundamental role is played by the Finite Element Analysis approach to predict the final residual stress profile. The FEA approach consists of either direct simulation of the LSP process or the application of the eigenstrain approach. The application of the eigenstrain theory in predicting residual stresses after LSP treatment in curved edges is the subject of this research.

An Analytical Model to Predict Residual Stress Field Induced by Laser Shock Peening

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Yongxiang Hu ◽  
Zhenqiang Yao ◽  
Jun Hu
Keyword(s):  
Residual Stress ◽  
Stress Field ◽  
Analytical Model ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Laser Shock ◽  
Residual Stress Field ◽  
Proposed Model ◽  
Shock Peening ◽  
The Impact

Laser shock peening (LSP) is an innovative surface treatment technique similar to shot peening. An analytical model to predict the residual stress field can obtain the impact effect much quickly, and will be invaluable in enabling a close-loop process control in production, saving time and cost of processing. A complete analytical model of LSP with some reasonable simplification is proposed to predict residual stresses in depth by a sequential application of a confined plasma development model and a residual stress model. The spatial distribution of the shock pressure and the high strain rate effect are considered in the model. Good agreements have been shown with several experimental measured results for various laser conditions and target materials, thus proving the validity of the proposed model.

Laser Shock Peening to Repair, Design and Manufacture Current and Future Aircraft Structures by Residual Stress Engineering

2014 ◽  
Vol 891-892 ◽  
pp. 992-1000 ◽  
Author(s):  
Domenico Furfari
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Crack Growth ◽  
Laser Shock Peening ◽  
Laser Shock ◽  
Aircraft Structures ◽  
Area Of Interest ◽  
Aircraft Manufacturing ◽  
Stress Engineering ◽  
Shock Peening

This paper will provide an overview on potential applications for the aerospace industry for repairing aircraft as well as to ensure salvage for identified hot spots in terms of fatigue and crack growth performance. Residual stress engineering is a field of engineering aiming to improve the economic and ecological impact of future aircraft structures by controlling the residual stresses induced by Laser Shock Peening (LSP). Managing the residual stresses for designing structures represents an innovative approach for next generation aircraft. Predicting crack turning induced via a LSP treatment and the optimization of the LSP treatment itself for reaching the crack growth design stress for the targeted weight benefit will be discussed. Advanced forming processes in aircraft manufacturing represent another potential area of interest and the benefits and challenges of applying laser peen forming in this context will be presented. The aeronautical industry requirements for future developments of the laser shock process will also be included for applications ranging from the repair environment to design and manufacturing of aircraft structures.

Numerical Study of Laser Shock Peening Effects on Alloy 600 Nozzles With Initial Residual Stresses

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Ji-Soo Kim ◽  
Hyun-Suk Nam ◽  
Yun-Jae Kim ◽  
Ju-Hee Kim
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Numerical Study ◽  
Laser Shock Peening ◽  
Tensile Residual Stress ◽  
Alloy 600 ◽  
Laser Shock ◽  
Near Surface ◽  
Rate Dependent ◽  
Shock Peening

This paper investigates the effect of initial residual stress and prestrain on residual stresses due to laser shock peening for Alloy 600 using numerical simulation. For simulation, the strain rate dependent Johnson–Cook hardening model with a Mie–Grüneisen equation of state is used. Simulation results are compared with published experimental data, showing good agreement. It is found that the laser shock peening (LSP) process is more effective for higher initial tensile residual stress and for larger initial prestrain in terms of compressive stress at the near surface. However, the effective depth decreases with increasing initial tensile residual stress and initial prestrain.

scholarly journals A Parametric Neutron Bragg Edge Imaging Study of Additively Manufactured Samples Treated by Laser Shock Peening

2021 ◽  
Author(s):  
Matteo Busi ◽  
Nikola Kalentics ◽  
Manuel Morgano ◽  
Seth Griffiths ◽  
Anton S. Tremsin ◽  
...  
Keyword(s):  
Residual Stress ◽  
Additive Manufacturing ◽  
Residual Stresses ◽  
Compressive Residual Stress ◽  
Laser Shock Peening ◽  
Powder Bed Fusion ◽  
Laser Shock ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Shock Peening

Abstract Laser powder bed fusion is an additive manufacturing technique extensively used for the production of metallic components. Despite this process has reached a status at which parts are produced with mechanical properties comparable to those from conventional production, it is still prone to introduce detrimental tensile residual stresses towards the surfaces along the building direction, implying negative consequences on fatigue life and resistance to crack formations. Laser shock peening (LSP) is a promising method adopted to compensate tensile residual stresses and to introduce beneficial compressive residual stress on the treated surfaces. Using neutron Bragg edge imaging, we perform a parametric study of LSP applied to 316L steel samples produced by laser powder bed fusion additive manufacturing. We include in the study the novel 3D-LSP technique, where samples are LSP treated also during the building process, at intermediate build layers. The LSP energy and spot overlap were set to either 1.0 or 1.5 J and 40% or 80% respectively. The results support the use of 3D-LSP treatment with the higher LSP laser energy and overlap applied, which showed a relative increase of surface compressive residual stress (CRS) and CRS depth by 57% and 104% respectively, compared to the conventional LSP treatment.

Sign in / Sign up

Export Citation Format

Share Document