In this study, Al-Mg-Sc aluminum alloys were fabricated using wire-arc directed energy deposition. The focus of the study was to analyze the microstructure and mechanical properties of these alloys. Comparative analysis was conducted on the samples obtained from the as-deposited and aging treated, respectively. Furthermore, the precipitation process of the second phases and the associated strengthening mechanism were elucidated. The findings revealed that the presence of precipitated Al3(Sc,Zr) particles acted as heterogeneous nucleation nuclei of α-Al, facilitating the formation of equiaxial grains. During the subsequent aging treatment, the secondary Al3(Sc,Zr) particles precipitated directly without transitioning through intermediate phases. Additionally, the experimental results demonstrated that these secondary Al3(Sc,Zr) phases hindered the dislocation movement, leading to enhanced mechanical properties in Al-Mg-Sc alloys through precipitation strengthening. In the horizontal direction, the average ultimate tensile strength (UTS) and yield strength (YS) were measured as 361 ± 5 MPa, 251 ± 4 MPa, and 281 ± 6 MPa, 179 ± 6 MPa in the vertical direction, respectively. The elongations were found to be 15.8 ± 0.8% and 4.0 ± 0.5% in the horizontal and vertical directions, respectively. The observed variations in mechanical properties were attributed to the presence of interlayer pores.
{"title":"Microstructure and mechanical properties of wire-arc directed energy deposited Al-Mg-Sc aluminum alloy: As-deposited and aging heat treated","authors":"Jiayuan Cui, Xinpeng Guo, Shuai Hao, Yuanzheng Zhao, Xuming Guo","doi":"10.1177/14644207241255197","DOIUrl":"https://doi.org/10.1177/14644207241255197","url":null,"abstract":"In this study, Al-Mg-Sc aluminum alloys were fabricated using wire-arc directed energy deposition. The focus of the study was to analyze the microstructure and mechanical properties of these alloys. Comparative analysis was conducted on the samples obtained from the as-deposited and aging treated, respectively. Furthermore, the precipitation process of the second phases and the associated strengthening mechanism were elucidated. The findings revealed that the presence of precipitated Al<jats:sub>3</jats:sub>(Sc,Zr) particles acted as heterogeneous nucleation nuclei of α-Al, facilitating the formation of equiaxial grains. During the subsequent aging treatment, the secondary Al<jats:sub>3</jats:sub>(Sc,Zr) particles precipitated directly without transitioning through intermediate phases. Additionally, the experimental results demonstrated that these secondary Al<jats:sub>3</jats:sub>(Sc,Zr) phases hindered the dislocation movement, leading to enhanced mechanical properties in Al-Mg-Sc alloys through precipitation strengthening. In the horizontal direction, the average ultimate tensile strength (UTS) and yield strength (YS) were measured as 361 ± 5 MPa, 251 ± 4 MPa, and 281 ± 6 MPa, 179 ± 6 MPa in the vertical direction, respectively. The elongations were found to be 15.8 ± 0.8% and 4.0 ± 0.5% in the horizontal and vertical directions, respectively. The observed variations in mechanical properties were attributed to the presence of interlayer pores.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"52 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141151516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1177/14644207241246118
Lucas Constantino, Panters Rodríguez-Bermudez, Alexandre Santos Francisco, Isamara Landim Nunes Araujo, Jorge A Rodríguez Durán
In general, oil reservoirs may consist of composite sedimentary structures composed of materials such as sand, clay, or limestone, which exhibit varying lithology due to sedimentary processes. A comprehensive knowledge of this lithology is essential for accurately assessing their hydrocarbon storage and production capacity. Additionally, this information is indispensable for the implementation of various recovery techniques such as waterflooding, gas injection, surfactant injection, polymer injection, alkaline water solution injection, and others. Highly viscous oil can exhibit non-Newtonian behavior during water injection in certain cases. The use of surfactants, alkaline, or polymer solutions in enhanced oil recovery also introduces non-Newtonian behavior. Recovery methods face challenges when non-Newtonian phases, gravity, and reservoir heterogeneity are combined. Against this backdrop, this work presents a mathematical model for immiscible two-phase flow in an axially composite reservoir with a periodic-layered structure. The model considers a non-Newtonian plastic Bingham-type phase extension of the Buckley-Leverett model. To address the porous medium’s heterogeneity with discontinuous flux functions, the numerical solutions were obtained using the Lax-Friedrichs and Lagrangian-Eulerian schemes. The numerical solutions were compared to analytical solutions obtained using an extended version of Oleinik’s geometric construction for discontinuous flux functions. The outcomes display shock and rarefaction waves, as well as a fixed shock due to the porous medium heterogeneity. The numerical results closely correspond with the analytical solutions, seen particularly in the greater accuracy of the Lagrangian-Eulerian method compared to the Lax-Friedrichs method.
{"title":"Vertical displacement of a non-Newtonian Bingham plastic by a Newtonian phase in an axially composite reservoir","authors":"Lucas Constantino, Panters Rodríguez-Bermudez, Alexandre Santos Francisco, Isamara Landim Nunes Araujo, Jorge A Rodríguez Durán","doi":"10.1177/14644207241246118","DOIUrl":"https://doi.org/10.1177/14644207241246118","url":null,"abstract":"In general, oil reservoirs may consist of composite sedimentary structures composed of materials such as sand, clay, or limestone, which exhibit varying lithology due to sedimentary processes. A comprehensive knowledge of this lithology is essential for accurately assessing their hydrocarbon storage and production capacity. Additionally, this information is indispensable for the implementation of various recovery techniques such as waterflooding, gas injection, surfactant injection, polymer injection, alkaline water solution injection, and others. Highly viscous oil can exhibit non-Newtonian behavior during water injection in certain cases. The use of surfactants, alkaline, or polymer solutions in enhanced oil recovery also introduces non-Newtonian behavior. Recovery methods face challenges when non-Newtonian phases, gravity, and reservoir heterogeneity are combined. Against this backdrop, this work presents a mathematical model for immiscible two-phase flow in an axially composite reservoir with a periodic-layered structure. The model considers a non-Newtonian plastic Bingham-type phase extension of the Buckley-Leverett model. To address the porous medium’s heterogeneity with discontinuous flux functions, the numerical solutions were obtained using the Lax-Friedrichs and Lagrangian-Eulerian schemes. The numerical solutions were compared to analytical solutions obtained using an extended version of Oleinik’s geometric construction for discontinuous flux functions. The outcomes display shock and rarefaction waves, as well as a fixed shock due to the porous medium heterogeneity. The numerical results closely correspond with the analytical solutions, seen particularly in the greater accuracy of the Lagrangian-Eulerian method compared to the Lax-Friedrichs method.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"146 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140927062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-06DOI: 10.1177/14644207241249765
Konrad Mäde, Uwe Reisgen, Rahul Sharma, Fatma Akyel, Simon Olschok, Maximilian Gamerdinger, Timm Evers, Karthik Ravi Krishna Murthy, Mirco Olesch, Johannes Kellerwessel, Guilherme Abreu Faria, Gleb Dovzhenko
Localised heat input, as it occurs in welding with moving heat sources, induces residual stresses and distortion in materials. The quantitative determination of residual stress evolution is difficult. Despite existing models, residual stress build-up with temperature progression is not fully understood. High-flux density X-rays from a synchrotron source allow the measurement of local strains in materials and improve the resolution of stress gradients as it permits small measurement volumes (Gibmeier et al., 2014). A laser beam welding process was used to perform linear bead-on-plate welds on bar steel samples. The X-ray diffraction system recorded the transient strain evolution. Multiple repetitions at different locations in the specimen were combined to develop a map of the strains present within the specimen. The temperature was measured locally at the surface of the sample. As the strain was determined within a measurement volume inside the sample, the temperature history over time had to be obtained as well. A numerical model was employed to determine the temperature inside the measurement volume. This model was calibrated using the transient surface temperatures and metallographic cross-sections. The result was a representation of the local strain superimposed on the temperature distribution. Analysis of this data correlation showed that a strain maximum occurs as a function of time and distance from the heat source, which is likely to coincide with the austenite-ferrite phase transformation temperature.
局部热输入（如在使用移动热源进行焊接时）会在材料中产生残余应力和变形。残余应力演变的定量测定非常困难。尽管已有模型，但人们对残余应力随温度升高而增加的情况还不完全了解。同步辐射源发出的高通量密度 X 射线可以测量材料中的局部应变，并提高应力梯度的分辨率，因为它允许小体积测量（Gibmeier 等人，2014 年）。利用激光束焊接工艺对棒材钢样品进行线性焊缝焊接。X 射线衍射系统记录了瞬态应变演变。结合试样不同位置的多次重复，绘制出试样内部的应变图。温度是在试样表面局部测量的。由于应变是在试样内部的测量体积内测定的，因此还必须获得随时间变化的温度历史。采用数值模型来确定测量体积内的温度。该模型使用瞬态表面温度和金相横截面进行校准。结果是在温度分布上叠加了局部应变。对这一数据相关性的分析表明，应变最大值是时间和与热源距离的函数，很可能与奥氏体-铁素体相变温度相吻合。
{"title":"Synchrotron EDXRD strain-temperature measurement during laser welding","authors":"Konrad Mäde, Uwe Reisgen, Rahul Sharma, Fatma Akyel, Simon Olschok, Maximilian Gamerdinger, Timm Evers, Karthik Ravi Krishna Murthy, Mirco Olesch, Johannes Kellerwessel, Guilherme Abreu Faria, Gleb Dovzhenko","doi":"10.1177/14644207241249765","DOIUrl":"https://doi.org/10.1177/14644207241249765","url":null,"abstract":"Localised heat input, as it occurs in welding with moving heat sources, induces residual stresses and distortion in materials. The quantitative determination of residual stress evolution is difficult. Despite existing models, residual stress build-up with temperature progression is not fully understood. High-flux density X-rays from a synchrotron source allow the measurement of local strains in materials and improve the resolution of stress gradients as it permits small measurement volumes (Gibmeier et al., 2014). A laser beam welding process was used to perform linear bead-on-plate welds on bar steel samples. The X-ray diffraction system recorded the transient strain evolution. Multiple repetitions at different locations in the specimen were combined to develop a map of the strains present within the specimen. The temperature was measured locally at the surface of the sample. As the strain was determined within a measurement volume inside the sample, the temperature history over time had to be obtained as well. A numerical model was employed to determine the temperature inside the measurement volume. This model was calibrated using the transient surface temperatures and metallographic cross-sections. The result was a representation of the local strain superimposed on the temperature distribution. Analysis of this data correlation showed that a strain maximum occurs as a function of time and distance from the heat source, which is likely to coincide with the austenite-ferrite phase transformation temperature.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"17 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140885556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1177/14644207241247741
Mateus Holanda Cardoso Maciel, Romulo do Nascimento Rodrigues, Camilo Augusto Santos Costa, Roberto de Araujo Bezerra, Vanessa Vieira Gonçalves, Thiago Victor Albuquerque de Freitas
Brakes play a vital role in vehicles, converting kinetic energy into heat and vibration. Brake squeal, an uncomfortable noise phenomenon, has been thoroughly researched in both drum and disc brakes. Many studies have explored how factors such as material, temperature, and operations impact brake instability and noise. Yet, commercial drum brake linings often contain hazardous asbestos. This poses health risks, exposing individuals to harmful airborne particles, particularly affecting lung health. Hence, current research aims to develop asbestos-free alternative linings, prioritizing reduced wear rates while maintaining effectiveness comparable to traditional ones. These alternatives primarily use organic materials for reinforcement. However, few studies have evaluated the performance of these biomaterial-based linings against commercial counterparts. This study aims to bridge this gap by analyzing a rear-axle drum brake from a heavy vehicle, comparing two linings: One commercially available and the other specially made with coconut shell reinforcement, in a finite element software. Five similar simulation stages were set for both linings in the ANSYS software. Each stage comprises transient thermal and static simulations. The input parameters were chosen to simulate a real braking situation, and the resulting pre-stress state was used to conduct complex modal analysis, which extracted the eigenvalues and values responsible for stability. The results proved that biomaterials such as coconut shells can be used for industrial purposes, such as the manufacture of a brake pad or lining, creating a cheaper, less polluting, and less brake squeal-inducing material.
{"title":"Brake squeal finite element performance comparison between commercial and coconut shell-reinforced material drum brake linings","authors":"Mateus Holanda Cardoso Maciel, Romulo do Nascimento Rodrigues, Camilo Augusto Santos Costa, Roberto de Araujo Bezerra, Vanessa Vieira Gonçalves, Thiago Victor Albuquerque de Freitas","doi":"10.1177/14644207241247741","DOIUrl":"https://doi.org/10.1177/14644207241247741","url":null,"abstract":"Brakes play a vital role in vehicles, converting kinetic energy into heat and vibration. Brake squeal, an uncomfortable noise phenomenon, has been thoroughly researched in both drum and disc brakes. Many studies have explored how factors such as material, temperature, and operations impact brake instability and noise. Yet, commercial drum brake linings often contain hazardous asbestos. This poses health risks, exposing individuals to harmful airborne particles, particularly affecting lung health. Hence, current research aims to develop asbestos-free alternative linings, prioritizing reduced wear rates while maintaining effectiveness comparable to traditional ones. These alternatives primarily use organic materials for reinforcement. However, few studies have evaluated the performance of these biomaterial-based linings against commercial counterparts. This study aims to bridge this gap by analyzing a rear-axle drum brake from a heavy vehicle, comparing two linings: One commercially available and the other specially made with coconut shell reinforcement, in a finite element software. Five similar simulation stages were set for both linings in the ANSYS software. Each stage comprises transient thermal and static simulations. The input parameters were chosen to simulate a real braking situation, and the resulting pre-stress state was used to conduct complex modal analysis, which extracted the eigenvalues and values responsible for stability. The results proved that biomaterials such as coconut shells can be used for industrial purposes, such as the manufacture of a brake pad or lining, creating a cheaper, less polluting, and less brake squeal-inducing material.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"38 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140630050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-16DOI: 10.1177/14644207241245431
FW Müller, J Liu, A Schiebahn, U Reisgen
Ultrasonic metal welding is a well-established solid state joining process for electrical applications. The process relies on the friction between workpieces and welding tools for joint formation. This friction is generated by the process force and the ultrasonic oscillation of the welding tools imposed on the workpieces. At such high frequencies, the occurrence of resonances in actual workpiece geometries is not surprising. It is known that critical dimensions in length and width lead to nearly no bond, depending on the welding frequency and the mechanical properties of the material. In real applications, this limits the possible designs of terminals and leads to extensive testing of clamping devices. It is also known that machine learning (ML) models for quality prediction based on power signals or tool oscillation can account for changes in welding position. In this study, we investigated the impact of part resonance and antiresonance on horn and anvil oscillation, power consumption and bond strength to identify typical behaviors induced by the workpieces. The influence of material thickness and roughness was considered, and numerical analysis of the natural frequencies of the workpieces was conducted. It can be shown that the results allow a distinction between the welding positions and workpiece geometries without directly measuring the oscillation patterns of the workpieces, allowing a simple validation of geometry weldability and clamping device in applications. Furthermore, the investigation allows the knowledge based specific deduction of signal parameters for future ML models, allowing a consideration of welding position and workpieces geometry with reduced test data.
超声波金属焊接是一种成熟的电气应用固态连接工艺。该工艺依靠工件和焊接工具之间的摩擦力形成接头。这种摩擦力由施加在工件上的加工力和焊接工具的超声波振荡产生。在如此高的频率下，实际工件几何形状出现共振并不奇怪。众所周知，根据焊接频率和材料的机械性能，长度和宽度的临界尺寸几乎不会产生结合。在实际应用中，这限制了端子的可能设计，并导致对夹紧装置进行大量测试。众所周知，基于功率信号或工具振荡的质量预测机器学习（ML）模型可以解释焊接位置的变化。在本研究中，我们研究了工件共振和反共振对喇叭和砧板振荡、功耗和粘接强度的影响，以确定工件诱发的典型行为。研究考虑了材料厚度和粗糙度的影响，并对工件的自然频率进行了数值分析。结果表明，无需直接测量工件的振荡模式，就能区分焊接位置和工件几何形状，从而在应用中对几何形状的可焊性和夹紧装置进行简单验证。此外，这项研究还能为未来的 ML 模型提供基于知识的特定信号参数推导，从而在减少测试数据的情况下考虑焊接位置和工件几何形状。
{"title":"Influence of workpiece geometry and natural frequencies on ultrasonic metal welding","authors":"FW Müller, J Liu, A Schiebahn, U Reisgen","doi":"10.1177/14644207241245431","DOIUrl":"https://doi.org/10.1177/14644207241245431","url":null,"abstract":"Ultrasonic metal welding is a well-established solid state joining process for electrical applications. The process relies on the friction between workpieces and welding tools for joint formation. This friction is generated by the process force and the ultrasonic oscillation of the welding tools imposed on the workpieces. At such high frequencies, the occurrence of resonances in actual workpiece geometries is not surprising. It is known that critical dimensions in length and width lead to nearly no bond, depending on the welding frequency and the mechanical properties of the material. In real applications, this limits the possible designs of terminals and leads to extensive testing of clamping devices. It is also known that machine learning (ML) models for quality prediction based on power signals or tool oscillation can account for changes in welding position. In this study, we investigated the impact of part resonance and antiresonance on horn and anvil oscillation, power consumption and bond strength to identify typical behaviors induced by the workpieces. The influence of material thickness and roughness was considered, and numerical analysis of the natural frequencies of the workpieces was conducted. It can be shown that the results allow a distinction between the welding positions and workpiece geometries without directly measuring the oscillation patterns of the workpieces, allowing a simple validation of geometry weldability and clamping device in applications. Furthermore, the investigation allows the knowledge based specific deduction of signal parameters for future ML models, allowing a consideration of welding position and workpieces geometry with reduced test data.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"57 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140609232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-13DOI: 10.1177/14644207241247236
Bahman Taherkhani, Asli Tuncay Atalay, Ozgur Atalay
The (comparative) study on the multidirectional piezo-resistive scenario of conventional and auxetic sensors is presented using silicone RTV2 as a base material coated with graphite powder as a sensing element. The key parameter of this comparison is the added area that appeared by applying the strain. The larger this parameter is, the larger the area for the sensing elements separation, and subsequently, the greater the sensitivity. To do the sensing performance test in a three-directional mode, a low-cost idea is to use a chuck lathe and an electric motor to open and close the chuck lath cyclically. The available commercial software ABAQUS2021 is used for numerical study. The sensitivity test on conventional and auxetic sensors in different loading modes shows that the performance of the auxetic sensor in unidirectional and bidirectional loading modes is 272% and 130% better than the conventional sensor, respectively. It means that if the added area for the two sensors is closer to each other, the sensory performance of the two sensors will be more similar. Although the sensing performance of the two sensors in the three-directional loading mode is almost equal, the consumed strain energy required to deform the conventional sensor is 30 times more than that of the auxetic one.
{"title":"A comparative study on the multidirectional piezo-resistive scenario of conventional and auxetic silicone-based sensors coated with graphite powder","authors":"Bahman Taherkhani, Asli Tuncay Atalay, Ozgur Atalay","doi":"10.1177/14644207241247236","DOIUrl":"https://doi.org/10.1177/14644207241247236","url":null,"abstract":"The (comparative) study on the multidirectional piezo-resistive scenario of conventional and auxetic sensors is presented using silicone RTV2 as a base material coated with graphite powder as a sensing element. The key parameter of this comparison is the added area that appeared by applying the strain. The larger this parameter is, the larger the area for the sensing elements separation, and subsequently, the greater the sensitivity. To do the sensing performance test in a three-directional mode, a low-cost idea is to use a chuck lathe and an electric motor to open and close the chuck lath cyclically. The available commercial software ABAQUS2021 is used for numerical study. The sensitivity test on conventional and auxetic sensors in different loading modes shows that the performance of the auxetic sensor in unidirectional and bidirectional loading modes is 272% and 130% better than the conventional sensor, respectively. It means that if the added area for the two sensors is closer to each other, the sensory performance of the two sensors will be more similar. Although the sensing performance of the two sensors in the three-directional loading mode is almost equal, the consumed strain energy required to deform the conventional sensor is 30 times more than that of the auxetic one.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"41 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-13DOI: 10.1177/14644207241243304
Rasoul Safdarian, Marco PL Parente
The high weight-to-strength ratio of AA6061 aluminum alloys presents increased potential applications in industries such as automotive and aircraft. However, its limited formability at room temperature (RT) restricts its usage. Therefore, in the conducted study, the formability of AA6061-T6 sheets with a thickness of 2 mm was investigated at different temperatures in the range of RT up to 300°C. Both experimental and numerical methods were employed to investigate the forming limit diagram (FLD) of an AA6061-T6 sheet. The tests were conducted using a non-isothermal Nakajima standard die under dry contact conditions. Two damage criteria, the Johnson–Cook and the ductile fracture criterion (DFC), were used in a thermomechanically coupled finite element analysis in Abaqus/Explicit to predict fracture in the AA6061 sheet. To examine the impact of temperature on the friction coefficient in the punch and sheet contact, an atomic force microscope was used to measure the roughness of the sheet, after the FLD tests, were conducted at different temperatures. Results indicate an increase in FLD levels from RT up to 100°C, followed by a decrease, for temperatures surpassing 100°C. Experimental findings underscored the significance of the adhesive wear at elevated temperatures, acting as a decisive factor that hampers the material flow and the sheet deformation, in the contact between the sheet and punch.
{"title":"Investigating the formability of 6061-T6 aluminum alloy sheets at elevated temperatures using experimental and numerical methods","authors":"Rasoul Safdarian, Marco PL Parente","doi":"10.1177/14644207241243304","DOIUrl":"https://doi.org/10.1177/14644207241243304","url":null,"abstract":"The high weight-to-strength ratio of AA6061 aluminum alloys presents increased potential applications in industries such as automotive and aircraft. However, its limited formability at room temperature (RT) restricts its usage. Therefore, in the conducted study, the formability of AA6061-T6 sheets with a thickness of 2 mm was investigated at different temperatures in the range of RT up to 300°C. Both experimental and numerical methods were employed to investigate the forming limit diagram (FLD) of an AA6061-T6 sheet. The tests were conducted using a non-isothermal Nakajima standard die under dry contact conditions. Two damage criteria, the Johnson–Cook and the ductile fracture criterion (DFC), were used in a thermomechanically coupled finite element analysis in Abaqus/Explicit to predict fracture in the AA6061 sheet. To examine the impact of temperature on the friction coefficient in the punch and sheet contact, an atomic force microscope was used to measure the roughness of the sheet, after the FLD tests, were conducted at different temperatures. Results indicate an increase in FLD levels from RT up to 100°C, followed by a decrease, for temperatures surpassing 100°C. Experimental findings underscored the significance of the adhesive wear at elevated temperatures, acting as a decisive factor that hampers the material flow and the sheet deformation, in the contact between the sheet and punch.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"17 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Cu–6Al–2Ni alloy has much higher ultimate tensile strength compared to pure copper and may potentially replace it in the dissimilar joints between titanium alloys and stainless steels. Laser welding of aluminum bronze to stainless steel has not been reported in the scientific literature, which motivated the present weldability study of Cu–6Al–2Ni/316L dissimilar joint with a continuous ytterbium Yb:YAG laser. Different laser spot offsets from the joint line were selected in order to produce the joints with various dilutions of welded materials. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) probe and X-ray diffraction (XRD) analyses of the melted zones were performed, along with microhardness measurements and tensile testing. The phase evolution in the obtained microstructures was evaluated using Thermo-Calc software. For the dilutions ranging from 23 to 63 at.% Cu, the melted zones showed globular microstructures with primary and secondary phase separation due to the miscibility gap existing in the Cu–Fe system. Lower Cu contents resulted in cellular γ-Fe structures with rare globular Cu-rich inclusions. The XRD analysis indicated the presence of ∼10% of ternary AlFe2Ni phase, however, it did not harm the mechanical properties of the welds. According to Thermo-Calc, this phase is formed from γ-Fe during the cooling process. Microhardness measurements did not indicate the embrittlement of the melted zones, which can be explained by the submicronic dispersion of AlFe2Ni. The welds exhibited a ductile fracture in Cu–6Al–2Ni at ultimate tensile strength of 350–420 MPa in a wide range of laser offsets, which is much higher than previously reported results for pure copper/316L joints.
{"title":"Dissimilar welding between Cu–6Al–2Ni alloy and stainless steel 316L using continuous ytterbium YAG laser","authors":"Nathan Haglon, Rodolphe Bolot, Iryna Tomashchuk, Alexandre Mathieu, Sébastien Lafaye","doi":"10.1177/14644207241245264","DOIUrl":"https://doi.org/10.1177/14644207241245264","url":null,"abstract":"The Cu–6Al–2Ni alloy has much higher ultimate tensile strength compared to pure copper and may potentially replace it in the dissimilar joints between titanium alloys and stainless steels. Laser welding of aluminum bronze to stainless steel has not been reported in the scientific literature, which motivated the present weldability study of Cu–6Al–2Ni/316L dissimilar joint with a continuous ytterbium Yb:YAG laser. Different laser spot offsets from the joint line were selected in order to produce the joints with various dilutions of welded materials. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) probe and X-ray diffraction (XRD) analyses of the melted zones were performed, along with microhardness measurements and tensile testing. The phase evolution in the obtained microstructures was evaluated using Thermo-Calc software. For the dilutions ranging from 23 to 63 at.% Cu, the melted zones showed globular microstructures with primary and secondary phase separation due to the miscibility gap existing in the Cu–Fe system. Lower Cu contents resulted in cellular γ-Fe structures with rare globular Cu-rich inclusions. The XRD analysis indicated the presence of ∼10% of ternary AlFe<jats:sub>2</jats:sub>Ni phase, however, it did not harm the mechanical properties of the welds. According to Thermo-Calc, this phase is formed from γ-Fe during the cooling process. Microhardness measurements did not indicate the embrittlement of the melted zones, which can be explained by the submicronic dispersion of AlFe<jats:sub>2</jats:sub>Ni. The welds exhibited a ductile fracture in Cu–6Al–2Ni at ultimate tensile strength of 350–420 MPa in a wide range of laser offsets, which is much higher than previously reported results for pure copper/316L joints.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"89 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1177/14644207241245857
M Kathiresan, R Jose Immanuel, Vasudevan Rajamohan
The effects of stretching and bending of concave, convex, and horizontal ribs on the energy absorption characteristics of modified hexagonal honeycomb structural panels are investigated under in-plane quasi-static compression loading conditions. In this regard, five hierarchical modified structural panel configurations were fabricated using polylactic acid material (PLA) via a fused filament 3D printer, ensuring uniform wall thickness in the 1.5–2 mm range. The panels included the regular hexagonal panel (RHP), regular hexagonal panel with concave rib (RHCP), regular hexagonal panel with convex rib (RHXP), regular hexagonal panel with concave and horizontal ribs (RHCRP), and regular hexagonal panel with convex and horizontal ribs (RHXRP). In-plane quasi-static compressive loading tests were conducted to analyze crush resistance characteristics, and buckling modes of the modified honeycomb panels were examined through experimental and finite element analysis procedures. The result indicates that the specific energy absorption capacity (SEA) of RHXRP is increasing significantly compared to the SEA capacity of other categories of the structures. The changes in failure modes and increased crush energy absorption characteristics of modified RHP with the introduction of concave, convex, and horizontal ribs are elaborated.
{"title":"Enhancing crashworthiness characteristics of modified hexagonal honeycomb structural panels through stretching and bending of ribs","authors":"M Kathiresan, R Jose Immanuel, Vasudevan Rajamohan","doi":"10.1177/14644207241245857","DOIUrl":"https://doi.org/10.1177/14644207241245857","url":null,"abstract":"The effects of stretching and bending of concave, convex, and horizontal ribs on the energy absorption characteristics of modified hexagonal honeycomb structural panels are investigated under in-plane quasi-static compression loading conditions. In this regard, five hierarchical modified structural panel configurations were fabricated using polylactic acid material (PLA) via a fused filament 3D printer, ensuring uniform wall thickness in the 1.5–2 mm range. The panels included the regular hexagonal panel (RHP), regular hexagonal panel with concave rib (RHCP), regular hexagonal panel with convex rib (RHXP), regular hexagonal panel with concave and horizontal ribs (RHCRP), and regular hexagonal panel with convex and horizontal ribs (RHXRP). In-plane quasi-static compressive loading tests were conducted to analyze crush resistance characteristics, and buckling modes of the modified honeycomb panels were examined through experimental and finite element analysis procedures. The result indicates that the specific energy absorption capacity (SEA) of RHXRP is increasing significantly compared to the SEA capacity of other categories of the structures. The changes in failure modes and increased crush energy absorption characteristics of modified RHP with the introduction of concave, convex, and horizontal ribs are elaborated.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"9 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1177/14644207241245256
Vinzenz Ginster, Maximilian Klaus Heym, Christoph Jürgen Anton Beier, Maike Epperlein, Alexander Schiebahn, Uwe Reisgen
Metal foils are being widely used, from the chemical or electronics sector to household appliances. The joining of these foils by adhesive bonding is often the preferred method due to discolouring and warping under the thermal stresses of other joining methods, such as welding. However, long curing times are a disadvantage of adhesive bonding compared to welding. The use of electromagnetic induction is a promising solution for accelerated curing. This work investigates induction heating for accelerated curing of 1-C epoxy adhesives for bonding of thin nickel foils. Process parameters for rapid curing of the adhesives were determined based on reaction kinetics using differential scanning calorimetry measurements. According to those results peel test specimens were fabricated, and the peel resistance was evaluated using a 90° peel load.
{"title":"Curing of epoxy adhesives between thin metal foils by means of inductive heating","authors":"Vinzenz Ginster, Maximilian Klaus Heym, Christoph Jürgen Anton Beier, Maike Epperlein, Alexander Schiebahn, Uwe Reisgen","doi":"10.1177/14644207241245256","DOIUrl":"https://doi.org/10.1177/14644207241245256","url":null,"abstract":"Metal foils are being widely used, from the chemical or electronics sector to household appliances. The joining of these foils by adhesive bonding is often the preferred method due to discolouring and warping under the thermal stresses of other joining methods, such as welding. However, long curing times are a disadvantage of adhesive bonding compared to welding. The use of electromagnetic induction is a promising solution for accelerated curing. This work investigates induction heating for accelerated curing of 1-C epoxy adhesives for bonding of thin nickel foils. Process parameters for rapid curing of the adhesives were determined based on reaction kinetics using differential scanning calorimetry measurements. According to those results peel test specimens were fabricated, and the peel resistance was evaluated using a 90° peel load.","PeriodicalId":20630,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications","volume":"20 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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