Frattura ed Integrita Strutturale最新文献

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A Study on Micro-structure, Hardness and Optimization of Wear Characteristics of Al6061/TiB2/CeO2 Hotrolled MMCs using Taguchi Method Taguchi法研究Al6061/TiB2/CeO2控制mmc的显微组织、硬度及磨损特性优化
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.12
S. R. Sreenivasa Iyengar, D. Sethuramu, M. Ravikumar
{"title":"A Study on Micro-structure, Hardness and Optimization of Wear Characteristics of Al6061/TiB2/CeO2 Hotrolled MMCs using Taguchi Method","authors":"S. R. Sreenivasa Iyengar, D. Sethuramu, M. Ravikumar","doi":"10.3221/igf-esis.65.12","DOIUrl":"https://doi.org/10.3221/igf-esis.65.12","url":null,"abstract":"Aluminium composites are extensively used in several industrial applications. The production of Metal Matrix Composite (MMCs) with varying wt. % of reinforcement/s leads to enhancement of wear and mechanical behavior. In the present work, the varying wt. % of TiB2 and constant wt. % of CeO2 particulates were reinforced in Al6061 alloy to manufacture hybrid Al MMCs by Vortex (Stircasting) technique. Developed hybrid MMCs were hotrolled at 515°C of temperature. Hardness of hybrid MMCs was evaluated by using hardness test rig (Vickers). Result revealed that the hardness strength of developed hybrid MMCs increased with increase of the reinforcement content. The rate of wear of developed hybrid MMCs was evaluated by using Pin on Disc wear test. Test trials were conducted according to Taguchi technique. L27 array was implemented for evaluation of data. Effect of varying factors on the rate of wear and COF was analyzed by applying ANOVA (Analysis of Variance) method. ANOVA outcomes showed that the reinforcement content had a more significant impact on wear behavior and COF of the MMCs. Finally, L27 array outcomes were verified through confirmation experiments. A wear fractography outcome shows the internal fractured structure of a wear specimen which was studied using a SEM.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43421534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Investigation on Microstructure, Hardness, Wear behavior and Fracture Surface Analysis of Strontium (Sr) and Calcium (Ca) Content A357 Modified Alloy by Statistical Technique 用统计技术研究锶钙改性A357合金的显微组织、硬度、磨损性能及断口分析
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.03
K. Ganesh, K. Hemachandra Reddy, S. Sudhakar Babu, R. Suresh
{"title":"Investigation on Microstructure, Hardness, Wear behavior and Fracture Surface Analysis of Strontium (Sr) and Calcium (Ca) Content A357 Modified Alloy by Statistical Technique","authors":"K. Ganesh, K. Hemachandra Reddy, S. Sudhakar Babu, R. Suresh","doi":"10.3221/igf-esis.65.03","DOIUrl":"https://doi.org/10.3221/igf-esis.65.03","url":null,"abstract":"The aluminum alloy are extensively used in several industrial applications. Stir casting is one of the most frequently accepted methods. In the present investigation, how the microstructure, mechanical and wear mechanics of A357 alloy were impacted by the presence of Sr/Ca was investigated. The outcomes revealed that addition of elements (Sr/Ca) enhance the microstructural features. Uniform dispersal of particulates (Sr/ Ca) in Al357 alloy and also the modified structure of silicon (Si) were observed. Hardness of modified alloy was evaluated by using hardness tester. A result reveals that hardness of modified alloy was improved by increasing in the Sr/Ca content. The wear rate of modified alloy was evaluated by using Pin and Disc wear test rig. Test trials were conducted according to Taguchi technique. L27 array was implemented for evaluation of data. The effect of varying parameters (factors) on wear loss and COF were analyzed using ANOVA (Analysis of Variance) method. ANOVA outcomes shown that, the Sr/Ca content has a better significant impact on wear behavior and COF of the modified alloy. A wear fractography result shows the internal fracture structure of a wornout surface which was studied by SEM analysis.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":"128 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41306587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Impacts of nano-clay particles and heat-treating on out-of-phase thermo-mechanical fatigue characteristics in piston aluminum-silicon alloys 纳米粘土颗粒和热处理对活塞式铝硅合金非相热机械疲劳特性的影响
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.15
H. Bahmanabadi, M. Azadi, A. Dadashi, J. Torkian, M. Parast, G. Winter, F. Grün
{"title":"Impacts of nano-clay particles and heat-treating on out-of-phase thermo-mechanical fatigue characteristics in piston aluminum-silicon alloys","authors":"H. Bahmanabadi, M. Azadi, A. Dadashi, J. Torkian, M. Parast, G. Winter, F. Grün","doi":"10.3221/igf-esis.65.15","DOIUrl":"https://doi.org/10.3221/igf-esis.65.15","url":null,"abstract":"Abstract. In this article, the effect of nano-clay particles and heat-treating on thermo-mechanical fatigue (TMF) behaviors and failures of piston aluminum-silicon (AlSi) alloys was investigated. For this purpose, thermo-mechanical fatigue tests were conducted under out-of-phase (OP) loading conditions. Two loading conditions were checked based on different maximum temperatures (250, 300, and 350 °C) and various thermo-mechanical loading factors (100, 125, and 150%). The minimum temperature was constant in all tests at 50 °C under a heating/cooling rate of 10 °C/s and a dwell time of 5 s. Results showed that the nano-composites had a longer fatigue lifetime, at least 2 times higher, compared to the Al alloy, when the maximum temperature was 250 °C and the thermo-mechanical loading factor was 100%. However, no effective change was seen for the stress value and the plastic strain. At higher maximum temperatures, the change in the material behavior was lower. The fracture analysis by scanning electron microscopy (SEM) demonstrated that both materials had a brittle behavior due to cleavage and quasi-cleavage marks. The damage mechanism was also due to the Si-rich phase and intermetallics, respectively for the crack propagation and the micro-crack initiation.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44668130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Damage and restoration of historical urban walls: literature review and case of studies 历史城墙的破坏与修复:文献综述与个案研究
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.13
M. Sassu, M. L. Puppio, Aida Safabakhsh
{"title":"Damage and restoration of historical urban walls: literature review and case of studies","authors":"M. Sassu, M. L. Puppio, Aida Safabakhsh","doi":"10.3221/igf-esis.65.13","DOIUrl":"https://doi.org/10.3221/igf-esis.65.13","url":null,"abstract":"Within this work, the causes of collapses and damages occurred in masonry artefacts have been evaluated to properly identify suitable monitoring and restoration methods. In this regard, a comprehensive literature review has been performed. Based on the results, the moisture has found to be a critical parameter, which affects the structural health of masonry artefacts. Diverse non-destructive methods were employed to measure the moisture and monitor the materials involved: the Infrared Thermography, the Electrical Resistivity Tomography and the Ground Penetrating Radar, the Laser Scanning and Digital Terrestrial Photogrammetry, the Global Navigation Satellite Systems, the Unilateral Nuclear Magnetic Resonance, the Laser-Induced Fluorescence technique, the Acoustic Imaging and the Acoustic Tomography, the Geographic Information System and on-site survey process as well as computer modeling of the structure with specific FEM software. Finally, the implementation of tie-beams, Fiber Reinforced Polymers layers, ventilation, draining systems, and high-quality materials are proposed as solutions for controlling the moisture effect and retrofitting.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48457689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Investigation into effective mechanical properties of porous material produced by the additive manufacturing method 增材制造多孔材料的有效力学性能研究
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.14
M. Fakoor, Seyed Mohammad Javad Tabatabaee
{"title":"Investigation into effective mechanical properties of porous material produced by the additive manufacturing method","authors":"M. Fakoor, Seyed Mohammad Javad Tabatabaee","doi":"10.3221/igf-esis.65.14","DOIUrl":"https://doi.org/10.3221/igf-esis.65.14","url":null,"abstract":"Porous materials are defined as materials that contain holes, voids, or spaces in their structures, which can be interconnected or isolated. In the most complex forms of these materials, the holes can have irregular shapes with a random distribution in size, location, and direction, making studying their properties a challenging problem. Additive manufacturing techniques offer opportunities to create complex structures, and in this paper, we investigate the effective mechanical properties of porous material produced by the Fused Displacement Modeling (FDM) technique. We also propose an algorithm for generating a porous body containing irregularly shaped holes with arbitrary distributions in size and location while maintaining specific porosity. Due to the orthotropic properties of bodies created by the FDM technique, Reinforced Isotropic Solid Modeling (RISM) is combined with existing theories that calculate the effective properties of isotropic materials. For the experiments, some modified standard specimen with a porosity of 0.05 to 0.40 has been fabricated, and the elastic modulus and ultimate stress have been calculated using the tensile test. Finally, the results are compared with experimental data.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47531493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Crack simulation for the cover of the landfill – A seismic design 垃圾填埋场覆盖层的裂缝模拟-抗震设计
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.09
A. Namdar, M. Karimpour-Fard, O. Mughieda, F. Berto, Nurmunira Muhammad
{"title":"Crack simulation for the cover of the landfill – A seismic design","authors":"A. Namdar, M. Karimpour-Fard, O. Mughieda, F. Berto, Nurmunira Muhammad","doi":"10.3221/igf-esis.65.09","DOIUrl":"https://doi.org/10.3221/igf-esis.65.09","url":null,"abstract":"The stability of the landfill is an environmental issue. The collapse of the landfill causes environmental pollution and influences human life. In the present study, the crack on the cover of the landfill was simulated. Rankine’s theory and the Phantom Node Method were used for the simulation length of the crack and the mechanism of the crack propagation in the nonlinear extended finite element method (NXFEM). Artificial Neural Networks (ANNs) based on Levenberg-Marquardt Algorithm and Abalone Rings Data Set mode were used to predict displacement in critical points of the model. The vibration mechanism of the landfill was changed in each model. During applying seismic load on the model, the optimized thickness of the clay cover on the landfill was discussed. The thickness of the landfill cover controls the seismic response of the landfill. The numerical simulation shows differential displacement of the landfill impacts on the crack propagation and the need for the appropriate design of the cover thickness of the landfill.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44992801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 Internal Technological Defects on the Mechanical Properties of Structural CFRP 内部工艺缺陷对CFRP结构力学性能的影响
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.06
D. Lobanov, S. Slovikov, E. Lunegova
{"title":"Influence of Internal Technological Defects on the Mechanical Properties of Structural CFRP","authors":"D. Lobanov, S. Slovikov, E. Lunegova","doi":"10.3221/igf-esis.65.06","DOIUrl":"https://doi.org/10.3221/igf-esis.65.06","url":null,"abstract":"The use of carbon-fiber composite materials (CFRP) in critical cases implies an increase in the resistance to the stability of their mechanical properties. For the purpose of in-depth analysis of defects in the experiments, an integrated approach to mechanical flaw detection and testing of CFRP is used. To determine the parameters of defects in ultrasonic diagnostic sensors and the method of infrared thermography. The main technological defects of structural carbon fiber in samples of the internal \"glueline defect\", are three geometric shapes (circle, square, rectangle) and a \"buckling\" inner layer. As a result of flaw detection of individual samples by ultrasonic diagnostics, data were obtained on the shape and size of defects such as \"glueline defect\" and \"buckling\". As a result of the study, tensile testing of the samples with and without defects was carried out using the Vic 3D system, the AMSY-6 acoustic emission system, and the FLIR SC7700M thermal imaging system. The tensile strength, elastic modulus, Poisson's ratio, and maximum fracture strains of the studied CFRP without defects and with defects are obtained. The effect of defective zones on the main mechanical parameters is determined. The investigated defects lead to a decrease in strength and elastic characteristics by at least 15% and 5%, respectively.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44929513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Structural Health Evaluation of Arch Bridge by Field Test and Optimized BPNN Algorithm 基于现场试验和优化BPNN算法的拱桥结构健康评价
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.11
Z. Xiong, Jiachen She, Zhuoxi Liang, Xulin Mou, Y. Zhang
{"title":"Structural Health Evaluation of Arch Bridge by Field Test and Optimized BPNN Algorithm","authors":"Z. Xiong, Jiachen She, Zhuoxi Liang, Xulin Mou, Y. Zhang","doi":"10.3221/igf-esis.65.11","DOIUrl":"https://doi.org/10.3221/igf-esis.65.11","url":null,"abstract":"Arch bridges play an important role in rural roads in China. Due to insufficient funds and a lack of management techniques, many rural arch bridges are in a state of disrepair, unable to meet the increasing transportation needs. Thus, it is of great significance to develop a set of rapid and economic damage identification procedures for the management and maintenance of old arch bridges. Sanliushui Bridge, located in Chenggu County, Hanzhong, is selected as a model case. Field tests and numerical simulations were carried out to identify the damage states of Sanliushui Bridge. The sum square of wavelet packet energy change rate, a damage identification index based on wavelet packet analysis method was implemented to process the measured data of the load test and the simulated data of the numerical calculation model with assumed damage. BPNN, GA-BPNN, PSO-BPNN and test data analysis are adopted to compare the measured data with the simulated data to quantitatively identify the damage degree of the selected bridge. By comparing the results of the two methods mentioned above, it is found that the proposed damage identification approach realized a precise damage identification of the selected arch bridges.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49014141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
High carbon steel/Inconel 718 bimetallic parts produced via Fused Filament Fabrication and Sintering 高碳钢/铬镍铁合金718双金属零件通过熔融长丝制造和烧结
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.16
P. Ferro, A. Fabrizi, F. Bonollo, Hamdi Elsayed, F. Berto, G. Savio
{"title":"High carbon steel/Inconel 718 bimetallic parts produced via Fused Filament Fabrication and Sintering","authors":"P. Ferro, A. Fabrizi, F. Bonollo, Hamdi Elsayed, F. Berto, G. Savio","doi":"10.3221/igf-esis.65.16","DOIUrl":"https://doi.org/10.3221/igf-esis.65.16","url":null,"abstract":"The possibility of producing high carbon steel/Inconel 718 bimetallic parts via Fused Filament Fabrication and Sintering is explored. Compatibility of the two alloys with particular attention to elements interdiffusion through the interface as well as the effect of the deposition strategy were analyzed. Microstructural features, relative density and parts shrinkage were investigated, as well. Although first-tentative process parameters values were not sufficient to reach an acceptable material densification, a good bonding between Inconel 718 and carbon steel was observed, suggesting the potential to obtain sound bimetallic parts with a great range of material properties. Due to a difference in densification kinetics, sintering temperature was revealed to be the most critical process parameter to optimize to minimize porosity.","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41509301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Glass Fiber for Improved Behavior of Light Expanded Clay Aggregate Concrete Beams: An Experimental Study 玻璃纤维改善轻膨胀粘土集料混凝土梁性能的试验研究
Frattura ed Integrita Strutturale Pub Date : 2023-06-22 DOI: 10.3221/igf-esis.65.01
Louay Aboul Nour, Mariam Gamal, Amr Ghoniem
{"title":"Glass Fiber for Improved Behavior of Light Expanded Clay Aggregate Concrete Beams: An Experimental Study","authors":"Louay Aboul Nour, Mariam Gamal, Amr Ghoniem","doi":"10.3221/igf-esis.65.01","DOIUrl":"https://doi.org/10.3221/igf-esis.65.01","url":null,"abstract":"Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively.  ","PeriodicalId":38546,"journal":{"name":"Frattura ed Integrita Strutturale","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47113128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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