Abstract Laser Beam Welding (LBW) is the fusion welding technique in which coalescence is produced by heating the work piece by impingement of concentrated beam of laser light. In this paper a full depth butt welding of alloy steel AISI 4130 and stainless steel AISI 310 of 2 mm thickness by using CO2 Laser Beam Welding machine has been performed. Design of experiment is done by using Taguchi method L25 i.e. level 5 by considering process parameters i.e. power, welding speed, beam angle, focal point position and focal length. The experimental output results that are measured for the mechanical properties of welds (Ultimate Tensile Strength and Hardness). The analysis was carried out to explain the influence of the LBW processing parameters values on the mechanical and microstructural aspects. The weld Joint is analysed by Optical Microstructure and Scanning Electron Microscopy (SEM). The Energy Dispersive X-Ray Analysis (EDAX) was carried out to determinate the chemical composition of the weld zone.
{"title":"Mechanical and Metallurgical Characterisation of CO2 Laser Beam Welding AISI 4130 and AISI 310 Sheets of Steel","authors":"Bijivemula Narayana Reddy, P. Hema, C. E. Reddy","doi":"10.2478/scjme-2021-0014","DOIUrl":"https://doi.org/10.2478/scjme-2021-0014","url":null,"abstract":"Abstract Laser Beam Welding (LBW) is the fusion welding technique in which coalescence is produced by heating the work piece by impingement of concentrated beam of laser light. In this paper a full depth butt welding of alloy steel AISI 4130 and stainless steel AISI 310 of 2 mm thickness by using CO2 Laser Beam Welding machine has been performed. Design of experiment is done by using Taguchi method L25 i.e. level 5 by considering process parameters i.e. power, welding speed, beam angle, focal point position and focal length. The experimental output results that are measured for the mechanical properties of welds (Ultimate Tensile Strength and Hardness). The analysis was carried out to explain the influence of the LBW processing parameters values on the mechanical and microstructural aspects. The weld Joint is analysed by Optical Microstructure and Scanning Electron Microscopy (SEM). The Energy Dispersive X-Ray Analysis (EDAX) was carried out to determinate the chemical composition of the weld zone.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130353336","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}
Chatha Jagjeet Singh, Kohli Prabhsharan Singh, Handa Amit
Abstract Friction welding is a solid-state welding system which welds materials without authentic melting it. This study explores papers of different researchers on the friction welding method and it has been observed that the welding parameters like friction time; friction pressure, forge time and forge pressure highly affect properties of welded joints. The reason for this investigation is to exhort industry and the insightful world regarding advantages of revolving friction welding so the technique may be utilized in an ideal manner.
{"title":"Exploration of Rotary Friction Welding Technique","authors":"Chatha Jagjeet Singh, Kohli Prabhsharan Singh, Handa Amit","doi":"10.2478/scjme-2021-0017","DOIUrl":"https://doi.org/10.2478/scjme-2021-0017","url":null,"abstract":"Abstract Friction welding is a solid-state welding system which welds materials without authentic melting it. This study explores papers of different researchers on the friction welding method and it has been observed that the welding parameters like friction time; friction pressure, forge time and forge pressure highly affect properties of welded joints. The reason for this investigation is to exhort industry and the insightful world regarding advantages of revolving friction welding so the technique may be utilized in an ideal manner.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133150636","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}
Abstract In this study, friction stir welding (FSW) and Tungsten gas welding (TIG) processes were used to weld 5 mm thick Al-4.2Mg-0.6Mn-0.4Sc-0.1Zr alloy plates. The FSwelds and TIG welds were tested for mechanical properties (hardness, ultimate tensile strength, bending strength and impact strength) by means of vicker’s hardness machine, universal testing machine and impact test machine respectively. The strength of the base material was higher, compared to the strength of the FSW and TIG welded joints. The strength of the TIG welded joint decreased, compared to the strength of the FSW welded joint. The microstructure features were also observed for base material with the aid of metallurgical microscope and compared the same with the microstructures of FSW and TIG welded joints. FSW change the material strength due to fine-grain refinement in the stir zone in Al-4.2Mg-0.6Mn-0.4Sc-0.1Zr alloy and therefore FS welded joint exhibited 91.6% joint efficiency followed by the TIG welded joint of 69.8%.
{"title":"Effect of TIG and FSW Welding Processes on Mechanical Properties of Al-4.2Mg-0.6Mn-0.4Sc-0.1Zr Alloy","authors":"Srinivasa Rao Mallipudi, Tangudu Sai Shankar, Perumalla Srikar, Uppda Bhanoji Rao, Yandra Chandrasekhar, Kambhampati Karthikeyan","doi":"10.2478/scjme-2021-0036","DOIUrl":"https://doi.org/10.2478/scjme-2021-0036","url":null,"abstract":"Abstract In this study, friction stir welding (FSW) and Tungsten gas welding (TIG) processes were used to weld 5 mm thick Al-4.2Mg-0.6Mn-0.4Sc-0.1Zr alloy plates. The FSwelds and TIG welds were tested for mechanical properties (hardness, ultimate tensile strength, bending strength and impact strength) by means of vicker’s hardness machine, universal testing machine and impact test machine respectively. The strength of the base material was higher, compared to the strength of the FSW and TIG welded joints. The strength of the TIG welded joint decreased, compared to the strength of the FSW welded joint. The microstructure features were also observed for base material with the aid of metallurgical microscope and compared the same with the microstructures of FSW and TIG welded joints. FSW change the material strength due to fine-grain refinement in the stir zone in Al-4.2Mg-0.6Mn-0.4Sc-0.1Zr alloy and therefore FS welded joint exhibited 91.6% joint efficiency followed by the TIG welded joint of 69.8%.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125293855","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}
Drátovská Veronika, S. Radek, Padovec Zdeněk, Růžička Pavel, Kratochvíl Adam
Abstract The aim of the study was to predict the fatigue life of metallic bone plates employing SIMULIA fe-safe software. Two materials commonly used for surgical implants were subjected to investigation: 1.4441 (ASTM F138) stainless steel for implants and Ti6Al4V ELI (ASTM F136) titanium alloy. The material parameters of the two materials were determined from experimental research. Four-point bending fatigue testing was conducted on two generations of bone plates in order to allow for the comparison of the prediction results with the measured data from the experiments.
摘要采用有限元软件SIMULIA对金属骨板进行疲劳寿命预测。研究了两种常用的外科植入物材料:用于植入物的1.4441 (ASTM F138)不锈钢和Ti6Al4V ELI (ASTM F136)钛合金。通过实验研究确定了两种材料的材料参数。为了将预测结果与实验实测数据进行比较,对两代骨板进行了四点弯曲疲劳试验。
{"title":"The Mechanical Properties and Fatigue Prediction of a New Generation of Osteosynthesis Devices","authors":"Drátovská Veronika, S. Radek, Padovec Zdeněk, Růžička Pavel, Kratochvíl Adam","doi":"10.2478/scjme-2021-0021","DOIUrl":"https://doi.org/10.2478/scjme-2021-0021","url":null,"abstract":"Abstract The aim of the study was to predict the fatigue life of metallic bone plates employing SIMULIA fe-safe software. Two materials commonly used for surgical implants were subjected to investigation: 1.4441 (ASTM F138) stainless steel for implants and Ti6Al4V ELI (ASTM F136) titanium alloy. The material parameters of the two materials were determined from experimental research. Four-point bending fatigue testing was conducted on two generations of bone plates in order to allow for the comparison of the prediction results with the measured data from the experiments.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123726580","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}
Abstract The heat transfer and pressure drop in a microchannel heat sink with 02 mixing chambers with inclined walls were numerically studied. The transport equations have been resolved by the finite volume method using ANSYS Fluent software. The operating fluids are water and Al2O3-water. The results obtained for Reynolds numbers ranging from 187 and 705 show that adding a micro-mixing chamber with a rectangular rib in the microchannel improves the heat transfer and increases the pressure drop compared to conventional microchannels. The new shape of the mixing chamber studied shows a net decrease in pressure drop, which improves the performance of the micro heat sink by 5.6%.
{"title":"Numerical Study of Laminar Forced Convection of Nanofluid in a New Microchannel Heat Sink","authors":"Bouhabel Bourhane, Kabar Yassine","doi":"10.2478/scjme-2021-0015","DOIUrl":"https://doi.org/10.2478/scjme-2021-0015","url":null,"abstract":"Abstract The heat transfer and pressure drop in a microchannel heat sink with 02 mixing chambers with inclined walls were numerically studied. The transport equations have been resolved by the finite volume method using ANSYS Fluent software. The operating fluids are water and Al2O3-water. The results obtained for Reynolds numbers ranging from 187 and 705 show that adding a micro-mixing chamber with a rectangular rib in the microchannel improves the heat transfer and increases the pressure drop compared to conventional microchannels. The new shape of the mixing chamber studied shows a net decrease in pressure drop, which improves the performance of the micro heat sink by 5.6%.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126999589","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}
Abstract Low surface roughness and high Material Removal Rate (MRR) are expected in most machining methods in general and milling method in particular. However, they sometimes do not occur, for example, the MRR is often small as the surface roughness is low. In this case, the decisions made should ensure that desires are simultaneously satisfied. This situation leads to a problem known as multi-criteria decision making (MCDM). In this study, five methods including EDAS, MARCOS, PIV, MOORA and TOPSIS are used together for the decision-making in the milling process. The purpose of the research is to determine the value of cutting parameters for both the low surface roughness and large MRR. The comparison of these methods for finding the best is carefully discussed as well.
{"title":"Application of EDAS, MARCOS, TOPSIS, MOORA and PIV Methods for Multi-Criteria Decision Making in Milling Process","authors":"D. Trung","doi":"10.2478/scjme-2021-0019","DOIUrl":"https://doi.org/10.2478/scjme-2021-0019","url":null,"abstract":"Abstract Low surface roughness and high Material Removal Rate (MRR) are expected in most machining methods in general and milling method in particular. However, they sometimes do not occur, for example, the MRR is often small as the surface roughness is low. In this case, the decisions made should ensure that desires are simultaneously satisfied. This situation leads to a problem known as multi-criteria decision making (MCDM). In this study, five methods including EDAS, MARCOS, PIV, MOORA and TOPSIS are used together for the decision-making in the milling process. The purpose of the research is to determine the value of cutting parameters for both the low surface roughness and large MRR. The comparison of these methods for finding the best is carefully discussed as well.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134472232","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}
Abstract This paper proposes a decision making approach based on the development of a fuzzy prognostic system to ensure the vibrations monitoring of a gas turbine based on real time information obtained from different installed sensors. In this approach the case of incomplete obtained data which may occur frequently is taken into account by using an approach of full data reconstitution form incomplete data. The proposed fuzzy prognostic system approach presented in this paper allows the analysis of the data obtained via the vibration indicators of a gas turbine system for the accurate identification of the faults to avoid the performance degradation of such systems. In order to prove the robustness of the proposed approach presented in this paper, several tested has been performed.
{"title":"Fuzzy Prognosis System for Decision Making to Vibrations Monitoring in Gas Turbine","authors":"Saadat Boulanouar, Hafaifa Ahmed, Belhadef Rachid, Kouzou Abdellah","doi":"10.2478/scjme-2021-0033","DOIUrl":"https://doi.org/10.2478/scjme-2021-0033","url":null,"abstract":"Abstract This paper proposes a decision making approach based on the development of a fuzzy prognostic system to ensure the vibrations monitoring of a gas turbine based on real time information obtained from different installed sensors. In this approach the case of incomplete obtained data which may occur frequently is taken into account by using an approach of full data reconstitution form incomplete data. The proposed fuzzy prognostic system approach presented in this paper allows the analysis of the data obtained via the vibration indicators of a gas turbine system for the accurate identification of the faults to avoid the performance degradation of such systems. In order to prove the robustness of the proposed approach presented in this paper, several tested has been performed.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114443824","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}
Abstract The purpose of this paper is to study on the power extraction of the hydrofoil by performance of the coupled oscillating heave and pitch motions. The numerical analysis is conducted by using the Reynolds Average Navier-Stokes (RANS) equations and the realizable k- ɛ turbulent model of the Star-CCM+ software. A 3D oscillating hydrofoil of NACA0015 section with aspect ratio of 7 is selected for the present analysis at two inflow velocities and three frequencies. The numerical results of lift and drag coefficients, horizontal and vertical forces coefficients, power efficiency in time domain and average value of those parameters are presented and discussed. According to the numerical results, the high efficiency of hydrofoil is found at the reduced frequency of 0.18 and the flow velocity of 1 m/s and the low efficiency is obtained at the reduction frequency of 0.06 and the flow velocity of 2 m/s. Moreover, the contour results of vorticity, streamline and pressure distribution are also presented and discussed. The computational model depicts clear vortex patterns surrounding the hydrofoil, which has a major impact on the power performance of oscillating hydrofoil.
{"title":"Hydrodynamic Performance of the 3D Hydrofoil at the Coupled Oscillating Heave and Pitch Motions","authors":"A. Abbasi, H. Ghassemi, G. He","doi":"10.2478/scjme-2021-0013","DOIUrl":"https://doi.org/10.2478/scjme-2021-0013","url":null,"abstract":"Abstract The purpose of this paper is to study on the power extraction of the hydrofoil by performance of the coupled oscillating heave and pitch motions. The numerical analysis is conducted by using the Reynolds Average Navier-Stokes (RANS) equations and the realizable k- ɛ turbulent model of the Star-CCM+ software. A 3D oscillating hydrofoil of NACA0015 section with aspect ratio of 7 is selected for the present analysis at two inflow velocities and three frequencies. The numerical results of lift and drag coefficients, horizontal and vertical forces coefficients, power efficiency in time domain and average value of those parameters are presented and discussed. According to the numerical results, the high efficiency of hydrofoil is found at the reduced frequency of 0.18 and the flow velocity of 1 m/s and the low efficiency is obtained at the reduction frequency of 0.06 and the flow velocity of 2 m/s. Moreover, the contour results of vorticity, streamline and pressure distribution are also presented and discussed. The computational model depicts clear vortex patterns surrounding the hydrofoil, which has a major impact on the power performance of oscillating hydrofoil.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126099512","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}
Abstract Energetics is connected with industry development of the country and determines its geographic layout into certain extent. This fact defines an important and also priority position of energetics in a developed society. On the other side it evokes trying to reach sustainability of the environment and nowadays also trying to reach decreasing of the carbon footprint of human activities. The goal of the article is to present general criteria for localisation of energetic cogeneration plants on biogass base, factors presentation and confrontation of current examples and new trends in shaping architecture under the influence of the development of modern technique and technology. The article analyses mass-composition and architectonic aspects of energetic plants of the chosen performed examples and on the model studies it documents the vision of new solutions on the background of equal, non-invasive and eco-friendly architecture in the surroundings.
{"title":"Reality and Vision of the Architecture for Cogeneration Plants for Energy Recovery","authors":"Ilkovič Ján, Meziani Yakoub","doi":"10.2478/scjme-2021-0024","DOIUrl":"https://doi.org/10.2478/scjme-2021-0024","url":null,"abstract":"Abstract Energetics is connected with industry development of the country and determines its geographic layout into certain extent. This fact defines an important and also priority position of energetics in a developed society. On the other side it evokes trying to reach sustainability of the environment and nowadays also trying to reach decreasing of the carbon footprint of human activities. The goal of the article is to present general criteria for localisation of energetic cogeneration plants on biogass base, factors presentation and confrontation of current examples and new trends in shaping architecture under the influence of the development of modern technique and technology. The article analyses mass-composition and architectonic aspects of energetic plants of the chosen performed examples and on the model studies it documents the vision of new solutions on the background of equal, non-invasive and eco-friendly architecture in the surroundings.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117167785","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}
Abstract This paper is focusing on the improvement of the accuracy of WEDM process for machining the precision-die angular stainless-steel parts. The controllable parameters are studied and analyzed by using Response Surface Method technique with respect to the responses of dimensional accuracy and surface quality. Then, these models are optimized by using the multi-objective optimization technique to realize optimal processing parameters. These optimal controllable parameters are ready for WEDM operating technicians’ use.
{"title":"Multi-Objective Optimization of Processing Parameters in WEDM with Stainless Steel-304 for Die-Angular Cutting","authors":"Le Van Sy","doi":"10.2478/scjme-2021-0025","DOIUrl":"https://doi.org/10.2478/scjme-2021-0025","url":null,"abstract":"Abstract This paper is focusing on the improvement of the accuracy of WEDM process for machining the precision-die angular stainless-steel parts. The controllable parameters are studied and analyzed by using Response Surface Method technique with respect to the responses of dimensional accuracy and surface quality. Then, these models are optimized by using the multi-objective optimization technique to realize optimal processing parameters. These optimal controllable parameters are ready for WEDM operating technicians’ use.","PeriodicalId":445896,"journal":{"name":"Strojnícky časopis - Journal of Mechanical Engineering","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122038621","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}