Theoretical and Applied Fracture Mechanics最新文献

英文中文

Influences of freeze–thaw cycles (FTC) on tensile properties and mixed-mode I/II fracture response of epoxy resin materials

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-17 DOI: 10.1016/j.tafmec.2024.104830

Jamal Bidadi, Hamed Saeidi Googarchin

Epoxy resins (ERs) are widely used in manufacturing polymeric components. However, their mechanical properties and fracture resistance often deteriorate under fluctuating environmental conditions, particularly freeze–thaw cycles (FTC) common in rainy and snowy environments. The general understanding of the degradation process induced by FTC on the mechanical and fracture properties of ERs helps engineers develop predictive models. While a few studies have addressed the effect of FTC on the tensile properties of bulk ERs, very little research has been done to study mixed-mode I/II fracture behavior under such cycling. This work deals with the gap by studying the aging effects of 21, 42, and 63 FTC on the tensile properties and mixed-mode I/II fracture toughness of one type of ER being used frequently as a matrix phase for the manufacturing of fibrous composites. In this regard, dumbbell-shaped and cracked short-bend beam (SBB) specimens were used to obtain the tensile and mixed-mode I/II fracture responses, respectively, after exposure to FTC. All the specimens experienced FTC by thawing it in water at 25 °C for 12 h followed by storing the specimens in a freezer at −25 °C for 12 h each. The findings revealed that all aged specimens exhibited significantly lower tensile strain and higher tensile strength compared to the non-aged specimen. Opposite to the increase in tensile strength, a steady decrease of mixed-mode I/II fracture toughness with increasing number of FTC was observed, evidencing the destructive effect of FTC on residual fracture toughness for pre-cracked ER specimens. The reduction in experimental effective fracture toughness slows after the 42nd freeze–thaw cycle, forming a plateau. Therefore, the endurance limit for the tested ER can be set at 0.35 to 0.5 times the fracture toughness of a non-aged specimen. Finally, the mixed-mode I-II fracture envelope was established with regard to the GMTS criterion for both non-aged and aged specimens, by considering the deleterious effect of FTC on either the critical distance or FPZ existing near the crack tip. The GMTS theoretical predictions aligned well with the experimental results.

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引用次数: 0

Weld crack detection in spiral-welded pipes by direct current potential drop method and backpropagation neural network

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-16 DOI: 10.1016/j.tafmec.2024.104817

Dexin Sun , Yujie Chen , Zhenjie Zhang , Qun Li , He Li , Yue Zhao , Junling Hou

Pipelines are essential for transportation, and fractures can lead to severe accidents. Accurately detecting weld cracks is vital for supporting the safe operation of large-diameter spiral-welded pipelines. The direct current potential drop method detects cracks by observing the discontinuity of the electrical potential field caused by cracks inside a current-carrying body. The variation in crack lengths and positions significantly affects the measured potential drops. Traditional calibration curves focus on the relationship between crack length and potential drops, but detecting crack position is also essential. This research introduces an innovative method to identify the position and length of weld cracks in spiral-welded pipes by combining the direct current potential drop method and the backpropagation neural network. Finite element models of spiral-welded pipes with varying crack positions and lengths were created, and extensive simulations were conducted to collect potential drops across the weld seams. A backpropagation neural network model is constructed and trained through deep learning technology. The well-trained backpropagation neural network can precisely predict the position and length of the weld crack by scanning the potential drops of the entire weld seam. Several experiments have been conducted to validate the proposed method for detecting weld cracks.

{"title":"Weld crack detection in spiral-welded pipes by direct current potential drop method and backpropagation neural network","authors":"Dexin Sun , Yujie Chen , Zhenjie Zhang , Qun Li , He Li , Yue Zhao , Junling Hou","doi":"10.1016/j.tafmec.2024.104817","DOIUrl":"10.1016/j.tafmec.2024.104817","url":null,"abstract":"<div><div>Pipelines are essential for transportation, and fractures can lead to severe accidents. Accurately detecting weld cracks is vital for supporting the safe operation of large-diameter spiral-welded pipelines. The direct current potential drop method detects cracks by observing the discontinuity of the electrical potential field caused by cracks inside a current-carrying body. The variation in crack lengths and positions significantly affects the measured potential drops. Traditional calibration curves focus on the relationship between crack length and potential drops, but detecting crack position is also essential. This research introduces an innovative method to identify the position and length of weld cracks in spiral-welded pipes by combining the direct current potential drop method and the backpropagation neural network. Finite element models of spiral-welded pipes with varying crack positions and lengths were created, and extensive simulations were conducted to collect potential drops across the weld seams. A backpropagation neural network model is constructed and trained through deep learning technology. The well-trained backpropagation neural network can precisely predict the position and length of the weld crack by scanning the potential drops of the entire weld seam. Several experiments have been conducted to validate the proposed method for detecting weld cracks.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104817"},"PeriodicalIF":5.0,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced fatigue crack growth rate prediction in alloy steels using particle swarm optimized neural network

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-15 DOI: 10.1016/j.tafmec.2024.104826

Harsh Kumar Bhardwaj , Mukul Shukla

In the manufacturing sector, fatigue crack growth (FCG) poses a critical challenge to the structural integrity and safety of components, with significant implications for human safety and economic impact. The relationship between stress intensity factor range (ΔK) and FCG rate (da/dN) is often nonlinear, even within the Paris region, influenced by factors like stress ratio (R-ratio), threshold values of ΔK (ΔK_th) and da/dN (da/dN_th), critical stress intensity factor (K_c), specimen geometry, mechanical properties, and alloy compositions. These complexities render traditional empirical methods inadequate for accurate FCG rate predictions. This study introduces a Particle Swarm Optimized Neural Network (PSONN) model, trained and tested across a range of alloy steels, including 316, 316 L, 316 L(N), AISI 301, AISI 302, 304, St 980, Q345qc, St-4340, and Fe 430D. The PSONN model outperforms traditional methods by delivering superior accuracy and reducing error in FCG rate prediction, highlighting its potential for improved safety and reliability in design.

{"title":"Enhanced fatigue crack growth rate prediction in alloy steels using particle swarm optimized neural network","authors":"Harsh Kumar Bhardwaj , Mukul Shukla","doi":"10.1016/j.tafmec.2024.104826","DOIUrl":"10.1016/j.tafmec.2024.104826","url":null,"abstract":"<div><div>In the manufacturing sector, fatigue crack growth (FCG) poses a critical challenge to the structural integrity and safety of components, with significant implications for human safety and economic impact. The relationship between stress intensity factor range (ΔK) and FCG rate (da/dN) is often nonlinear, even within the Paris region, influenced by factors like stress ratio (R-ratio), threshold values of ΔK (ΔK<sub>th</sub>) and da/dN (da/dN<sub>th</sub>), critical stress intensity factor (K<sub>c</sub>), specimen geometry, mechanical properties, and alloy compositions. These complexities render traditional empirical methods inadequate for accurate FCG rate predictions. This study introduces a Particle Swarm Optimized Neural Network (PSONN) model, trained and tested across a range of alloy steels, including 316, 316 L, 316 L(N), AISI 301, AISI 302, 304, St 980, Q345qc, St-4340, and Fe 430D. The PSONN model outperforms traditional methods by delivering superior accuracy and reducing error in FCG rate prediction, highlighting its potential for improved safety and reliability in design.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104826"},"PeriodicalIF":5.0,"publicationDate":"2024-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Remaining fatigue life estimation under varying amplitude cyclic loading conditions combining ultrasonic waves and relative strain measurements for aluminum 6061-T6 plates with a notch

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-15 DOI: 10.1016/j.tafmec.2024.104825

Ohjun Kwon , Hyung Jin Lim , Hoon Sohn

In this study, a method for estimating the remaining fatigue life of notched aluminum plate structures under varying amplitude loading conditions was proposed using ultrasonic waves and relative strain measurements. To generate and measure ultrasonic waves, three macro-fiber composite (MFC) transducers were installed on the target structure under an unknown static uniaxial loading level. The unknown static-loading-induced strain at the time of MFC transducer installation was estimated using the acoustoelastic effect without any reference data obtained from the zero-loading condition. In addition, a strain gauge was used to measure the relative strain induced by various amplitude cyclic loading conditions after estimating an unknown static strain. Absolute cyclic strain monitoring was performed by combining the estimated unknown static strain (mean strain) and the measured relative strain (strain range). Subsequently, using the Walker equation, the monitored absolute cyclic strains under various mean strains and strain ranges were converted into an equivalent uniform cyclic strain with a constant mean strain and strain range. Finally, the remaining fatigue life was estimated from the equivalent uniform cyclic strain and the pre-obtained strain–life curve. The performance of the proposed method was experimentally evaluated using notched aluminum 6061-T6 plate specimens under varying amplitude cyclic loading conditions.

{"title":"Remaining fatigue life estimation under varying amplitude cyclic loading conditions combining ultrasonic waves and relative strain measurements for aluminum 6061-T6 plates with a notch","authors":"Ohjun Kwon , Hyung Jin Lim , Hoon Sohn","doi":"10.1016/j.tafmec.2024.104825","DOIUrl":"10.1016/j.tafmec.2024.104825","url":null,"abstract":"<div><div>In this study, a method for estimating the remaining fatigue life of notched aluminum plate structures under varying amplitude loading conditions was proposed using ultrasonic waves and relative strain measurements. To generate and measure ultrasonic waves, three macro-fiber composite (MFC) transducers were installed on the target structure under an unknown static uniaxial loading level. The unknown static-loading-induced strain at the time of MFC transducer installation was estimated using the acoustoelastic effect without any reference data obtained from the zero-loading condition. In addition, a strain gauge was used to measure the relative strain induced by various amplitude cyclic loading conditions after estimating an unknown static strain. Absolute cyclic strain monitoring was performed by combining the estimated unknown static strain (mean strain) and the measured relative strain (strain range). Subsequently, using the Walker equation, the monitored absolute cyclic strains under various mean strains and strain ranges were converted into an equivalent uniform cyclic strain with a constant mean strain and strain range. Finally, the remaining fatigue life was estimated from the equivalent uniform cyclic strain and the pre-obtained strain–life curve. The performance of the proposed method was experimentally evaluated using notched aluminum 6061-T6 plate specimens under varying amplitude cyclic loading conditions.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104825"},"PeriodicalIF":5.0,"publicationDate":"2024-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influences of arch height and stress sate on tunnel failure: Insights from orthogonal true-triaxial experiment

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-14 DOI: 10.1016/j.tafmec.2024.104824

Kang Peng , Ji Ren , Tao Wu , Guansheng Yi , Song Luo , Kun Luo

The surrounding rock of underground tunnel often fails under a variety of influencing factors. In this study, the influences of four factors (the arch height, initial burial depth stress, loading rate, horizontal stress state) on the failure of arch tunnel were revealed based on the orthogonal true-triaxial experiment on cubic granite samples with an arch hole. The results indicate that the true-triaxial experiment reproduces the spalling phenomenon observed in underground tunnel, with a characterization that flake-like rock fragments exfoliated from tunnel sidewalls. The vertical initial failure stress first decreases and then increases with a reduction in arch height, while it increases with the initial burial depth stress and loading rate. It also increases with increasing X-direction stress and decreasing Y-direction stress. The vertical stress corresponding to the maximum acoustic emission (AE) count of specimens with different arch heights follows the order of f/B (arch height/tunnel width) = 1/2 > f/B = 1/3 > f/B = 1/4. Importantly, the influence degree from greatest to least of the four factors on the vertical initial failure stress of arch tunnel is as follows: arch height, loading rate, horizontal stress state, and initial burial depth stress. The findings provide valuable guidance for the instability prevention and control during excavation of underground arch tunnels.

{"title":"Influences of arch height and stress sate on tunnel failure: Insights from orthogonal true-triaxial experiment","authors":"Kang Peng , Ji Ren , Tao Wu , Guansheng Yi , Song Luo , Kun Luo","doi":"10.1016/j.tafmec.2024.104824","DOIUrl":"10.1016/j.tafmec.2024.104824","url":null,"abstract":"<div><div>The surrounding rock of underground tunnel often fails under a variety of influencing factors. In this study, the influences of four factors (the arch height, initial burial depth stress, loading rate, horizontal stress state) on the failure of arch tunnel were revealed based on the orthogonal true-triaxial experiment on cubic granite samples with an arch hole. The results indicate that the true-triaxial experiment reproduces the spalling phenomenon observed in underground tunnel, with a characterization that flake-like rock fragments exfoliated from tunnel sidewalls. The vertical initial failure stress first decreases and then increases with a reduction in arch height, while it increases with the initial burial depth stress and loading rate. It also increases with increasing X-direction stress and decreasing Y-direction stress. The vertical stress corresponding to the maximum acoustic emission (AE) count of specimens with different arch heights follows the order of <em>f/B</em> (arch height/tunnel width) = 1/2 > <em>f/B</em> = 1/3 > <em>f/B</em> = 1/4. Importantly, the influence degree from greatest to least of the four factors on the vertical initial failure stress of arch tunnel is as follows: arch height, loading rate, horizontal stress state, and initial burial depth stress. The findings provide valuable guidance for the instability prevention and control during excavation of underground arch tunnels.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104824"},"PeriodicalIF":5.0,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of mode III stress fields around a line crack at the corner of a semicircular cavity

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-13 DOI: 10.1016/j.tafmec.2024.104822

Kao-Hao Chang , An-Chieh Chou , Chang-Wei Huang , Ching-Chiang Chuang

The analysis of mode III stress fields surrounding crack tips remains a fundamental concern across multiple engineering fields. This study presents a simplified model of a semicircular cavity with a corner line crack under remote antiplane loading conditions. A semi-analytical, mesh-free method incorporating the region-point-matching technique is established to address horizontally oriented line cracks. This method employs singular eigenfunctions to characterize the crack-tip singularity and satisfy zero-stress conditions along the crack surface. The accuracy of the semi-analytical method is verified through extended finite element method (XFEM) simulations conducted using Abaqus. The analyses are extended to cases of inclined line cracks, revealing a “cavity shielding” effect where specific orientations reduce stress intensity factors (SIFs). The horizontal crack configuration provides upper-bound SIF values, enhancing the practical utility of the proposed semi-analytical solution. Comparative analyses between circular and semicircular cavities demonstrate a notable reversal in SIFs at a crack length to cavity radius ratio of 0.75. An approximate formula for SIFs of horizontally oriented cracks is established and validated within its applicable range.

{"title":"Analysis of mode III stress fields around a line crack at the corner of a semicircular cavity","authors":"Kao-Hao Chang , An-Chieh Chou , Chang-Wei Huang , Ching-Chiang Chuang","doi":"10.1016/j.tafmec.2024.104822","DOIUrl":"10.1016/j.tafmec.2024.104822","url":null,"abstract":"<div><div>The analysis of mode III stress fields surrounding crack tips remains a fundamental concern across multiple engineering fields. This study presents a simplified model of a semicircular cavity with a corner line crack under remote antiplane loading conditions. A semi-analytical, mesh-free method incorporating the region-point-matching technique is established to address horizontally oriented line cracks. This method employs singular eigenfunctions to characterize the crack-tip singularity and satisfy zero-stress conditions along the crack surface. The accuracy of the semi-analytical method is verified through extended finite element method (XFEM) simulations conducted using Abaqus. The analyses are extended to cases of inclined line cracks, revealing a “cavity shielding” effect where specific orientations reduce stress intensity factors (SIFs). The horizontal crack configuration provides upper-bound SIF values, enhancing the practical utility of the proposed semi-analytical solution. Comparative analyses between circular and semicircular cavities demonstrate a notable reversal in SIFs at a crack length to cavity radius ratio of 0.75. An approximate formula for SIFs of horizontally oriented cracks is established and validated within its applicable range.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104822"},"PeriodicalIF":5.0,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Ca and Zn on fracture stress of crack in the interface of bi-crystal Mg with atomistic simulation

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-12 DOI: 10.1016/j.tafmec.2024.104820

Zheng Guang Liu , Jian Sui , Pan Long An

The effect of Ca and Zn on fracture stress of mode I crack in a magnesium bi-crystal interface is investigated using a molecular dynamics (MD) method with a Ca-Zn-Mg ternary EAM potential at 300 K. The anisotropic elastic theory of interface crack is applied in MD simulation to obtain the quantitative critical fracture stress. MD simulations show that the fracture stress decreases and increases with Ca and Zn addition, respectively. The change trend of fracture stress in MD results is consistent with the results in fracture experiments. In addition, it is found that the formed energy of crack is a convenient quantity to reflect the qualitative trend of Ca and Zn on fracture stress. It is also seen in MD simulation that the cracks almost grow along the grain boundaries in a cleavage manner, and the dislocations do not appear near the crack tip. The ratios between the surface energy and the unstable stacking energy are larger than 0.7 regardless of Ca or Zn addition, meaning that the magnesium alloys are brittle in the present crack model.

引用次数: 0

A comparison of approaches to compute the crack opening/sliding within the phase-field method

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-12 DOI: 10.1016/j.tafmec.2024.104818

L. Chen , B. Li , G. Cui , R. de Borst

The phase-field method has been used widely in the analysis of fracture due to its easy description of cracks, which obviates the introduction of geometric discontinuities in the domain. The discrete crack is regularised as a smeared surface, defined by a phase-field variable, and there is no need to explicitly define a crack path. Due to the smeared nature of the phase-field method, the crack opening and crack sliding do not directly result from a phase-field computation, but need to be computed a posteriori. Herein, we provide a complete overview of methods to compute the crack opening and crack sliding, resulting from the phase-field computation, namely the auxiliary field method, the integration method and the Taylor expansion method. The advantages and disadvantages of the methods are demonstrated by numerical examples, for crack opening/sliding. The auxiliary field and integration methods provide stable and relatively accurate results, but the Taylor expansion method is the faster approach to compute the crack opening/sliding, with a guaranteed accuracy.

引用次数: 0

Foreword to ‘Special issue on small scale specimen testing’ 小规模试样测试特刊 "前言

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-12 DOI: 10.1016/j.tafmec.2024.104823

Robert Lancaster, Nagamani Jaya Balila, Raghu Prakash, Bernd Gludovatz, Vikram Jayaram, Daniel Gianola, Roberto Lacalle

引用次数: 0

Research on the prediction method of corrosion fatigue crack extension rate of aluminum alloy based on BB-GBRT algorithm

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Theoretical and Applied Fracture Mechanics

Pub Date : 2024-12-11 DOI: 10.1016/j.tafmec.2024.104807

Xueyuan Li , Yongzhen Zhang , Leijiang Yao , Xiaoyan Tong

Aluminium alloy, as a commonly used material in modern aircraft structures, is susceptible to corrosion damage under the influence of high temperature, high humidity, salt spray and other climatic conditions. Corrosion damage in the structure under the action of fatigue loading will accelerate the formation and expansion of cracks, shortening the fatigue life of the material. In order to accurately predict the fatigue life of aluminium alloy under different corrosion damage and loading conditions, this paper collects data on the material, environment, load and crack expansion rate of aluminium alloy corrosion fatigue crack expansion, and establishes a prediction model for the corrosion fatigue crack expansion rate of aluminium alloy by combining the Bayesian Bootstrap algorithm and the Gradient Boosting Regression Tree(GBRT) model.The Bayesian Bootstrap algorithm was used to calculate the feature importance for feature dimensionality reduction, and the mean square error (

MSE

) and the coefficient of determination (

R^{2}

) were used as evaluation indexes to calculate the accuracy of the prediction model. The results show that the Bayesian Bootstrap + GBRT model is better than the traditional GBRT model and Bayesian linear regression model (BLR) in predicting the corrosion crack extension rate of aluminium alloy, with better generalization ability and prediction accuracy, which can provide reference for the subsequent prediction of aluminium alloy corrosion fatigue life.

{"title":"Research on the prediction method of corrosion fatigue crack extension rate of aluminum alloy based on BB-GBRT algorithm","authors":"Xueyuan Li , Yongzhen Zhang , Leijiang Yao , Xiaoyan Tong","doi":"10.1016/j.tafmec.2024.104807","DOIUrl":"10.1016/j.tafmec.2024.104807","url":null,"abstract":"<div><div>Aluminium alloy, as a commonly used material in modern aircraft structures, is susceptible to corrosion damage under the influence of high temperature, high humidity, salt spray and other climatic conditions. Corrosion damage in the structure under the action of fatigue loading will accelerate the formation and expansion of cracks, shortening the fatigue life of the material. In order to accurately predict the fatigue life of aluminium alloy under different corrosion damage and loading conditions, this paper collects data on the material, environment, load and crack expansion rate of aluminium alloy corrosion fatigue crack expansion, and establishes a prediction model for the corrosion fatigue crack expansion rate of aluminium alloy by combining the Bayesian Bootstrap algorithm and the Gradient Boosting Regression Tree(GBRT) model.The Bayesian Bootstrap algorithm was used to calculate the feature importance for feature dimensionality reduction, and the mean square error (<span><math><mrow><mi>MSE</mi></mrow></math></span>) and the coefficient of determination (<span><math><msup><mrow><mi>R</mi></mrow><mn>2</mn></msup></math></span>) were used as evaluation indexes to calculate the accuracy of the prediction model. The results show that the Bayesian Bootstrap + GBRT model is better than the traditional GBRT model and Bayesian linear regression model (BLR) in predicting the corrosion crack extension rate of aluminium alloy, with better generalization ability and prediction accuracy, which can provide reference for the subsequent prediction of aluminium alloy corrosion fatigue life.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"136 ","pages":"Article 104807"},"PeriodicalIF":5.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Theoretical and Applied Fracture Mechanics

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