Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.089
Shujun Chen, Tianming Li, Fan Jiang, Goukai Zhang, Shitong Fang
In response to the inconsistency between the features obtained by deep learning models and the quality features reflected by the physical laws of the welding process, this study proposes a solution by integrating a physical prior information model with a CNN model. Initially, the physical laws of the welding process are utilized to annotate the arc, weld pool, and weld seam features relevant to quality, which are then acquired through image processing algorithms, thereby converting the physical laws into a prior information model. Subsequently, this prior information model guides the CNN model for quality recognition, and the CNN model's attention to features is explained through visualization methods to elucidate the relationship between features and quality recognition. Experimental results demonstrate that under the guidance of the prior information model, the CNN model not only automatically focuses on features relevant to quality but also achieves a differential feature attention strategy, thereby improving the recognition accuracy of different outcomes. This research provides a new perspective for deep learning in the field of welding quality recognition.
{"title":"Enhancing VPPA welding quality prediction: A hybrid model integrating prior physical knowledge and CNN analysis","authors":"Shujun Chen, Tianming Li, Fan Jiang, Goukai Zhang, Shitong Fang","doi":"10.1016/j.jmapro.2024.09.089","DOIUrl":"10.1016/j.jmapro.2024.09.089","url":null,"abstract":"<div><div>In response to the inconsistency between the features obtained by deep learning models and the quality features reflected by the physical laws of the welding process, this study proposes a solution by integrating a physical prior information model with a CNN model. Initially, the physical laws of the welding process are utilized to annotate the arc, weld pool, and weld seam features relevant to quality, which are then acquired through image processing algorithms, thereby converting the physical laws into a prior information model. Subsequently, this prior information model guides the CNN model for quality recognition, and the CNN model's attention to features is explained through visualization methods to elucidate the relationship between features and quality recognition. Experimental results demonstrate that under the guidance of the prior information model, the CNN model not only automatically focuses on features relevant to quality but also achieves a differential feature attention strategy, thereby improving the recognition accuracy of different outcomes. This research provides a new perspective for deep learning in the field of welding quality recognition.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1282-1295"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.114
Wei Cheng , Xiu-Bo Liu , Fei-Zhi Zhang , Xin-Gong Li , Ji-Xiang Liang , Xiang-Yu Liu , Jun Zheng , Jin-Peng Zhu
During manufacturing processes, alloys face increasingly demanding requirements for their mechanical and tribological properties, underscoring the importance of revealing their deformation mechanisms. This study employed molecular dynamics simulation to construct models of FeCrNi (C1), FeCoCrNi (C2), FeCrNiCu (C3), and FeCoCrNiCu (C4), investigating the tribological properties of C1 alloy under various conditions and the mechanical properties across a wide temperature range (223–1073 K). The results indicate that the elastic modulus of the alloys follows the order C2 > C4 > C3 > C1 across the temperature range of 223 K to 1073 K. The elastic modulus increases with rising temperatures and decreases before rising once again as temperatures decrease. The phase transitions become more pronounced below 300 K. The addition of Co elements to the FeCrNi alloy contributes to fine-grain strengthening, uniform distribution of internal stress and strain, reduction in local stress concentration, and improvement of the alloy ductility and tensile strength. Compared to sliding friction, rolling friction reduces the number of worn atoms; however, the tensile and shear effects cause an increase in the stress gradient, leading to more severe subsurface damage and shear deformation. Temperature significantly affects the tribological properties of the alloys: phase transitions at high temperatures promote dislocation slip and plastic deformation, while at low temperatures, higher hardness and strength are observed. The roughness of stacking faults is greatly influenced by temperature, with an increase at the low-temperature range (223–273 K), a decrease in the mid-temperature range (273–673 K), and a smoother surface at the high-temperature range (673–1073 K). The research aims to provide a deeper understanding of the excellent mechanical and tribological properties of FeCrNi alloy at the micro/nano scales, thereby advancing their application and development in manufacturing processes.
在制造过程中，合金的机械和摩擦学性能面临着越来越苛刻的要求，因此揭示其变形机理显得尤为重要。本研究采用分子动力学模拟构建了铁铬镍（C1）、铁钴铬镍（C2）、铁铬镍铜（C3）和铁钴铬镍铜（C4）的模型，研究了 C1 合金在各种条件下的摩擦学性能以及在较宽温度范围（223-1073 K）内的力学性能。结果表明，在 223 K 至 1073 K 的温度范围内，合金的弹性模量遵循 C2 > C4 > C3 > C1 的顺序。在铁铬镍合金中添加 Co 元素有助于细晶粒强化、均匀分布内部应力和应变、减少局部应力集中以及提高合金的延展性和抗拉强度。与滑动摩擦相比，滚动摩擦减少了磨损原子的数量；然而，拉伸和剪切效应会导致应力梯度增加，从而导致更严重的表面下损伤和剪切变形。温度对合金的摩擦学特性有很大影响：高温下的相变会促进位错滑移和塑性变形，而在低温下则会产生更高的硬度和强度。堆叠断层的粗糙度受温度影响很大，在低温范围（223-273 K）会增加，在中温范围（273-673 K）会减少，而在高温范围（673-1073 K）表面会更光滑。该研究旨在深入了解铁铬镍合金在微米/纳米尺度上的优异机械和摩擦学特性，从而推动其在制造工艺中的应用和发展。
{"title":"Mechanical properties, nano-tribological behavior and deformation mechanism of FeCrNi MEA with the addition of Co/Cu: Molecular dynamics simulation","authors":"Wei Cheng , Xiu-Bo Liu , Fei-Zhi Zhang , Xin-Gong Li , Ji-Xiang Liang , Xiang-Yu Liu , Jun Zheng , Jin-Peng Zhu","doi":"10.1016/j.jmapro.2024.09.114","DOIUrl":"10.1016/j.jmapro.2024.09.114","url":null,"abstract":"<div><div>During manufacturing processes, alloys face increasingly demanding requirements for their mechanical and tribological properties, underscoring the importance of revealing their deformation mechanisms. This study employed molecular dynamics simulation to construct models of FeCrNi (C1), FeCoCrNi (C2), FeCrNiCu (C3), and FeCoCrNiCu (C4), investigating the tribological properties of C1 alloy under various conditions and the mechanical properties across a wide temperature range (223–1073 K). The results indicate that the elastic modulus of the alloys follows the order C2 > C4 > C3 > C1 across the temperature range of 223 K to 1073 K. The elastic modulus increases with rising temperatures and decreases before rising once again as temperatures decrease. The phase transitions become more pronounced below 300 K. The addition of Co elements to the FeCrNi alloy contributes to fine-grain strengthening, uniform distribution of internal stress and strain, reduction in local stress concentration, and improvement of the alloy ductility and tensile strength. Compared to sliding friction, rolling friction reduces the number of worn atoms; however, the tensile and shear effects cause an increase in the stress gradient, leading to more severe subsurface damage and shear deformation. Temperature significantly affects the tribological properties of the alloys: phase transitions at high temperatures promote dislocation slip and plastic deformation, while at low temperatures, higher hardness and strength are observed. The roughness of stacking faults is greatly influenced by temperature, with an increase at the low-temperature range (223–273 K), a decrease in the mid-temperature range (273–673 K), and a smoother surface at the high-temperature range (673–1073 K). The research aims to provide a deeper understanding of the excellent mechanical and tribological properties of FeCrNi alloy at the micro/nano scales, thereby advancing their application and development in manufacturing processes.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1348-1359"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.120
Emine Şirin , Çağrı Vakkas Yıldırım , Şenol Şirin , Turgay Kıvak , Murat Sarıkaya
Despite being expensive and difficult to process, the Ti6Al4V alloy is a vital component for crucial industries. To improve its machinability and accomplish sustainable production, environmentally friendly cooling and lubricating agencies are used. Studies on the machinability of the alloy are still necessary because of its unique features and significance in vital industries like aerospace, defense, and medicine. Therefore, this investigation focuses on tool wear, temperature, and surface integrity for sustainable milling Ti6Al4V under various machining environments, i.e., dry, pure-MQL, LN2, hBN, CuO-doped nanofluids, and hybrid methods. The produced nanofluids' thermophysical and rheological characteristics were examined in the study's initial phase. Because of the results from the first stage, machining performance indicators were assessed in the subsequent milling experiments. As a result, CuO-doped nanofluids gave improved results in terms of viscosity and pH. The best results obtained in the LN2 + CuO hybrid cooling lubrication environment in important machinability outcomes such as tool wear and surface integrity were attributed to the rheological properties of CuO-doped nanofluid and its harmonious cooperation with LN2-cryogenic cooling.
{"title":"Comprehensive analysis of cutting temperature, tool wear, surface integrity and tribological properties in sustainable milling of Ti6Al4V alloy: LN2, nanofluid and hybrid machining","authors":"Emine Şirin , Çağrı Vakkas Yıldırım , Şenol Şirin , Turgay Kıvak , Murat Sarıkaya","doi":"10.1016/j.jmapro.2024.09.120","DOIUrl":"10.1016/j.jmapro.2024.09.120","url":null,"abstract":"<div><div>Despite being expensive and difficult to process, the Ti6Al4V alloy is a vital component for crucial industries. To improve its machinability and accomplish sustainable production, environmentally friendly cooling and lubricating agencies are used. Studies on the machinability of the alloy are still necessary because of its unique features and significance in vital industries like aerospace, defense, and medicine. Therefore, this investigation focuses on tool wear, temperature, and surface integrity for sustainable milling Ti6Al4V under various machining environments, i.e., dry, pure-MQL, LN<sub>2</sub>, hBN, CuO-doped nanofluids, and hybrid methods. The produced nanofluids' thermophysical and rheological characteristics were examined in the study's initial phase. Because of the results from the first stage, machining performance indicators were assessed in the subsequent milling experiments. As a result, CuO-doped nanofluids gave improved results in terms of viscosity and pH. The best results obtained in the LN<sub>2</sub> + CuO hybrid cooling lubrication environment in important machinability outcomes such as tool wear and surface integrity were attributed to the rheological properties of CuO-doped nanofluid and its harmonious cooperation with LN<sub>2</sub>-cryogenic cooling.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1360-1371"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.098
John D. Kechagias , Stephanos P. Zaoutsos
Material extrusion is increasingly used to make functional parts in small batches that are challenging to produce with traditional machining. Also, intensive efforts are being made to develop new eco–friendly materials. This work investigates the strength of multilayer samples made in sandwich form with 4–5–4 layers of 0.3 mm layer thickness, externally with polylacticacid wood (PLA/wood, 61.5 % of specimens' material) and internally with pure PLA (38.5 % of specimens' material), under tensile loads. The intent is to investigate the possibility of manufacturing biocompatible components that take advantage of the excellent surface properties of wood externally and the durability properties of PLA internally. For this purpose, a designed experiment following the Taguchi L9 orthogonal array was prepared, and nine samples were fabricated: three with pure PLA, three with a sandwich PLA/wood–PLA–PLA/wood form, and three with composite PLA/wood form. Printing speed and temperature were varied during the experiment, and the results were examined using the analysis of means and residuals. Sandwich specimens improve tensile strength and elastic modulus by 100 % and 50 % compared to PLA/wood components while exhibiting slightly better surface roughness parameters, i.e., Ra and Rz, about ∼10 % lower values. Additionally, even if PLA parts showed better strength and surface texture than sandwich parts (∼100 % and ∼56 % higher tensile strength and elastic modulus), they had lower performance in terms of PLA–PLA/wood material ratio, i.e., 160 % more PLA than sandwich parts. The findings of this research, with the potential to design functional and sustainable new products with optimal performance, are significant and can be exploited in various industries.
{"title":"An assessment of PLA/wood with PLA core sandwich multilayer component tensile strength under different 3D printing conditions","authors":"John D. Kechagias , Stephanos P. Zaoutsos","doi":"10.1016/j.jmapro.2024.09.098","DOIUrl":"10.1016/j.jmapro.2024.09.098","url":null,"abstract":"<div><div>Material extrusion is increasingly used to make functional parts in small batches that are challenging to produce with traditional machining. Also, intensive efforts are being made to develop new eco–friendly materials. This work investigates the strength of multilayer samples made in sandwich form with 4–5–4 layers of 0.3 mm layer thickness, externally with polylacticacid wood (PLA/wood, 61.5 % of specimens' material) and internally with pure PLA (38.5 % of specimens' material), under tensile loads. The intent is to investigate the possibility of manufacturing biocompatible components that take advantage of the excellent surface properties of wood externally and the durability properties of PLA internally. For this purpose, a designed experiment following the Taguchi L<sub>9</sub> orthogonal array was prepared, and nine samples were fabricated: three with pure PLA, three with a sandwich PLA/wood–PLA–PLA/wood form, and three with composite PLA/wood form. Printing speed and temperature were varied during the experiment, and the results were examined using the analysis of means and residuals. Sandwich specimens improve tensile strength and elastic modulus by 100 % and 50 % compared to PLA/wood components while exhibiting slightly better surface roughness parameters, i.e., Ra and Rz, about ∼10 % lower values. Additionally, even if PLA parts showed better strength and surface texture than sandwich parts (∼100 % and ∼56 % higher tensile strength and elastic modulus), they had lower performance in terms of PLA–PLA/wood material ratio, i.e., 160 % more PLA than sandwich parts. The findings of this research, with the potential to design functional and sustainable new products with optimal performance, are significant and can be exploited in various industries.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1240-1249"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.113
Bao Qu , Chunzhang Zhao , Kehuan Wang , Jie Zhao , Shanshan Cui , Bin Gao , Gang Liu
The simultaneous achievement of high strength and precision in the fabrication of titanium alloy thin-walled components is a long-standing issue. This work proposes a novel integrated forming process, named Hot Forming with In-situ Stress Relaxation-Aging (short for HF-ISRA) to solve the special issue. In contrast to usual isothermal forming, the forming temperature in the proposed process is raised to the solution treatment temperature. Dies at a lower temperature realize in-situ stress relaxation-aging after hot forming. The role of the dies, in addition to forming, is also achieved post-forming heat treatment. This novel process comprises three main steps: solution heat treatment, rapid forming at solution temperature, and in-situ stress relaxation-aging. An experimental prototype of HF-ISRA was developed for V-bending test, in which a sheet blank was rapidly heated using electric current and the forming die was heated using heating rods. The process window of the proposed HF-ISRA was established based on the V-bending and uniaxial tensile tests of the TA15 titanium alloy. The results showed that compared with cold forming, the springback angle obtained using the optimized HF-ISRA decreased by 97.8 %, from 9°06′ to only 12′. The tensile strength at room temperature and 500 °C was improved by 4.4 % and 10.9 % compared with the as-received material, respectively. The relaxation mechanisms of αs were the precipitation, growth, and then globularization. The relaxation mechanism of αp was dislocation movements. The strength improvement in HF-ISRA was due to the formation of αs and dislocations strengthening. The stress-induced twinning in αs was also a contributor. The proposed novel process provides a new route for the fabrication of titanium alloy thin-walled components with high precision and strength.
在制造钛合金薄壁部件时，如何同时实现高强度和高精度是一个长期存在的问题。为解决这一特殊问题，本研究提出了一种新型集成成形工艺，命名为 "原位应力松弛-时效热成形"（简称 HF-ISRA）。与通常的等温成形不同，该工艺中的成形温度提高到了固溶处理温度。温度较低的模具可在热成形后实现原位应力松弛时效。模具的作用除了成型外，还实现了成型后的热处理。这种新型工艺包括三个主要步骤：固溶热处理、在固溶温度下快速成型和原位应力松弛时效。开发了用于 V 形弯曲试验的 HF-ISRA 实验原型，其中使用电流快速加热板材坯料，并使用加热棒加热成型模具。根据 TA15 钛合金的 V 形弯曲和单轴拉伸试验，确定了拟议 HF-ISRA 的工艺窗口。结果表明，与冷成形相比，使用优化的 HF-ISRA 所获得的回弹角降低了 97.8%，从 9°06′ 降至仅 12′。室温和 500 °C 下的拉伸强度分别比初始材料提高了 4.4% 和 10.9%。αs的弛豫机制为沉淀、生长和球化。αp 的弛豫机制是位错运动。HF-ISRA 的强度提高是由于 αs 的形成和位错的强化。应力引起的αs孪晶也是一个原因。所提出的新工艺为制造具有高精度和高强度的钛合金薄壁部件提供了一条新途径。
{"title":"A novel integrated hot forming with in-situ stress relaxation-aging for titanium alloy thin-walled components","authors":"Bao Qu , Chunzhang Zhao , Kehuan Wang , Jie Zhao , Shanshan Cui , Bin Gao , Gang Liu","doi":"10.1016/j.jmapro.2024.09.113","DOIUrl":"10.1016/j.jmapro.2024.09.113","url":null,"abstract":"<div><div>The simultaneous achievement of high strength and precision in the fabrication of titanium alloy thin-walled components is a long-standing issue. This work proposes a novel integrated forming process, named Hot Forming with In-situ Stress Relaxation-Aging (short for HF-ISRA) to solve the special issue. In contrast to usual isothermal forming, the forming temperature in the proposed process is raised to the solution treatment temperature. Dies at a lower temperature realize in-situ stress relaxation-aging after hot forming. The role of the dies, in addition to forming, is also achieved post-forming heat treatment. This novel process comprises three main steps: solution heat treatment, rapid forming at solution temperature, and in-situ stress relaxation-aging. An experimental prototype of HF-ISRA was developed for V-bending test, in which a sheet blank was rapidly heated using electric current and the forming die was heated using heating rods. The process window of the proposed HF-ISRA was established based on the V-bending and uniaxial tensile tests of the TA15 titanium alloy. The results showed that compared with cold forming, the springback angle obtained using the optimized HF-ISRA decreased by 97.8 %, from 9°06′ to only 12′. The tensile strength at room temperature and 500 °C was improved by 4.4 % and 10.9 % compared with the as-received material, respectively. The relaxation mechanisms of α<sub>s</sub> were the precipitation, growth, and then globularization. The relaxation mechanism of α<sub>p</sub> was dislocation movements. The strength improvement in HF-ISRA was due to the formation of α<sub>s</sub> and dislocations strengthening. The stress-induced twinning in α<sub>s</sub> was also a contributor. The proposed novel process provides a new route for the fabrication of titanium alloy thin-walled components with high precision and strength.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1296-1308"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.103
Jian Cheng , Hongqin Lei , Yong Xiao , Linjie Zhao , Mingjun Chen , Youwang Hu , Qi Liu , Dinghuai Yang , Wenyu Ding , Guang Chen
Laser-induced damage points (known as defects) would seriously reduce the service life of large-aperture KDP optics in high-power laser devices. The ball-end milling procedure is recognized as an efficient method for creating a Gaussian mitigation pit (GMP) to restore the optical transmission performance of functional KDP crystals by removing defects. Nevertheless, achieving smooth and flawless Gaussian curved microstructures is a massive challenge for soft-brittle KDP crystals. Herein, a judging criterion of the ductile-regime machining for the GMP is developed by the models of uncut chip thickness (UCT) and critical milling depth. Simultaneously, the obtained judging criterion can be validated by the microstructure fabrication experiments. Besides, considering the spindle vibration, plowing effect, and machined surface texture, the influence of spindle speed (n), feed rate (f), and tool mark interval (d) on the surface formation mechanism of the GMP is analyzed, respectively. It can be discovered that the n of up to 60,000 r/min can lead to severe velocity fluctuation of the motion system, increasing the UCT and causing brittle fractures on the KDP surface. A low f can result in an undesirable plowing phenomenon, and a large number of crystal materials are accumulated in the up-cut process. Once the f reaches 72 mm/min, the tool path would fluctuate significantly, resulting in poor GMP surface texture. When the d exceeds 15 μm, the surface quality of the GMP can no longer meet the engineering requirements of the Ra ≤ 50 nm. Moreover, the optimized processing parameters of the microstructure fabrication are 47,800 r/min in the n, 30 mm/min in the f, and 5 μm in the d. This study can provide crucial guidance for obtaining the ultra-smooth and defect-free GMP processed in the ductile regime, which would resultantly possess significant theoretical importance and practical value in enhancing the optical properties of flawed KDP crystals.
激光诱发的损伤点（称为缺陷）会严重缩短高功率激光设备中大孔径 KDP 光学元件的使用寿命。球端铣削程序被认为是一种有效的方法，可以通过消除缺陷来创建高斯缓和凹坑（GMP），从而恢复功能性 KDP 晶体的光学传输性能。然而，对于软脆的 KDP 晶体来说，实现光滑无瑕的高斯曲线微结构是一项巨大的挑战。本文通过未切削切屑厚度（UCT）和临界铣削深度模型，建立了 GMP 的韧性机制加工判断标准。同时，所获得的判断标准可通过微结构制造实验进行验证。此外，考虑到主轴振动、耕作效应和加工表面纹理，分别分析了主轴转速（n）、进给速度（f）和刀痕间隔（d）对 GMP 表面形成机理的影响。结果发现，当 n 高达 60,000 r/min 时，会导致运动系统的速度剧烈波动，增加 UCT，使 KDP 表面产生脆性断裂。过低的 f 会导致不良的犁耕现象，并在上切过程中积累大量晶体材料。一旦 f 达到 72 mm/min，刀具路径就会出现明显波动，导致 GMP 表面纹理不佳。当 d 超过 15 μm 时，GMP 的表面质量已无法满足 Ra ≤ 50 nm 的工程要求。此外，微结构制造的优化加工参数为 n 值 47800 r/min、f 值 30 mm/min 和 d 值 5 μm。这项研究为获得在韧性机制下加工的超光滑无缺陷 GMP 提供了重要指导，从而在提高有缺陷 KDP 晶体的光学性能方面具有重要的理论意义和实用价值。
{"title":"Achievement of ductile-regime removal in fabricating Gaussian curved microstructure processed by micro ball-end milling on soft-brittle KDP surface","authors":"Jian Cheng , Hongqin Lei , Yong Xiao , Linjie Zhao , Mingjun Chen , Youwang Hu , Qi Liu , Dinghuai Yang , Wenyu Ding , Guang Chen","doi":"10.1016/j.jmapro.2024.09.103","DOIUrl":"10.1016/j.jmapro.2024.09.103","url":null,"abstract":"<div><div>Laser-induced damage points (known as defects) would seriously reduce the service life of large-aperture KDP optics in high-power laser devices. The ball-end milling procedure is recognized as an efficient method for creating a Gaussian mitigation pit (GMP) to restore the optical transmission performance of functional KDP crystals by removing defects. Nevertheless, achieving smooth and flawless Gaussian curved microstructures is a massive challenge for soft-brittle KDP crystals. Herein, a judging criterion of the ductile-regime machining for the GMP is developed by the models of uncut chip thickness (UCT) and critical milling depth. Simultaneously, the obtained judging criterion can be validated by the microstructure fabrication experiments. Besides, considering the spindle vibration, plowing effect, and machined surface texture, the influence of spindle speed (<em>n</em>), feed rate (<em>f</em>), and tool mark interval (<em>d</em>) on the surface formation mechanism of the GMP is analyzed, respectively. It can be discovered that the <em>n</em> of up to 60,000 r/min can lead to severe velocity fluctuation of the motion system, increasing the UCT and causing brittle fractures on the KDP surface. A low <em>f</em> can result in an undesirable plowing phenomenon, and a large number of crystal materials are accumulated in the up-cut process. Once the <em>f</em> reaches 72 mm/min, the tool path would fluctuate significantly, resulting in poor GMP surface texture. When the <em>d</em> exceeds 15 μm, the surface quality of the GMP can no longer meet the engineering requirements of the <em>Ra</em> ≤ 50 nm. Moreover, the optimized processing parameters of the microstructure fabrication are 47,800 r/min in the <em>n</em>, 30 mm/min in the <em>f</em>, and 5 μm in the <em>d</em>. This study can provide crucial guidance for obtaining the ultra-smooth and defect-free GMP processed in the ductile regime, which would resultantly possess significant theoretical importance and practical value in enhancing the optical properties of flawed KDP crystals.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1230-1239"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmapro.2024.09.075
Jianping Yang, Liming Wang, Yang Fang, Fangyi Li, Jianfeng Li
End-mills are used widely in industry, in which efficient chip evacuation and enhanced tool performance are directly influenced by the flute shapes. Generally, complex grinding wheels are employed to create intricate flute shapes with CNC grinding. In the kinematic of flute grinding, several transcendental equations with high non-linearity is derived and required to be solved. In some cases, the explicit expression for flute cannot be derived and the numerical method are generally applied, which requires various derivation or numerical program for different flute shapes. To address these challenges, this paper proposed a GPU-based approach for 5-axis flute grinding of end-mills with complex grinding wheel. In this method, a mesh model of the grinding wheel was established to transform the above complex equations into finding a set of point cloud which satisfied the envelope condition. To accelerate the computation time for searching those point cloud, a generalized GPU parallel processing algorithm were used to execute multiple compute threads. The validity of the approach was verified through a series of experiments. It demonstrated that this method achieved remarkable precision and broad applicability, fulfilling the diverse requirements of various grinding wheels and flute shapes. Furthermore, the high efficiency and versatility of this approach make it have great potential in the application of flute-grinding with various complex wheel in real-time path planning.
{"title":"A GPU-based approach for 5-axis flute grinding of end-mills with complex grinding wheel","authors":"Jianping Yang, Liming Wang, Yang Fang, Fangyi Li, Jianfeng Li","doi":"10.1016/j.jmapro.2024.09.075","DOIUrl":"10.1016/j.jmapro.2024.09.075","url":null,"abstract":"<div><div>End-mills are used widely in industry, in which efficient chip evacuation and enhanced tool performance are directly influenced by the flute shapes. Generally, complex grinding wheels are employed to create intricate flute shapes with CNC grinding. In the kinematic of flute grinding, several transcendental equations with high non-linearity is derived and required to be solved. In some cases, the explicit expression for flute cannot be derived and the numerical method are generally applied, which requires various derivation or numerical program for different flute shapes. To address these challenges, this paper proposed a GPU-based approach for 5-axis flute grinding of end-mills with complex grinding wheel. In this method, a mesh model of the grinding wheel was established to transform the above complex equations into finding a set of point cloud which satisfied the envelope condition. To accelerate the computation time for searching those point cloud, a generalized GPU parallel processing algorithm were used to execute multiple compute threads. The validity of the approach was verified through a series of experiments. It demonstrated that this method achieved remarkable precision and broad applicability, fulfilling the diverse requirements of various grinding wheels and flute shapes. Furthermore, the high efficiency and versatility of this approach make it have great potential in the application of flute-grinding with various complex wheel in real-time path planning.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1250-1262"},"PeriodicalIF":6.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmapro.2024.09.107
Mainak Pal, Anupam Agrawal, Chandrakant K. Nirala
Micro-forming is an emerging micro-manufacturing process for the fabrication of miniature parts/components made of ultra-thin sheets (foils), forged billets, rods, etc. Achieving high formability in the micro-incremental sheet forming (μISF) process is difficult due to the size-effect and non-optimal selection of process parameters viz. step depth (∆z). The major sources of size-effects are pure volume source, surface-to-volume ratio, thickness-to-grain-size (t/d ratio), surface structure scalability, etc. In the micro-scale processes, studying the grain size of the material is crucial to understand the deformation behaviour. Additionally, the anisotropy is very prominent in thin foils and affects the micro-forming process adversely. In the present work, the intrinsic anisotropy of the foils is minimized through controlled heat treatment, and varying grain sizes, having different microstructures, are generated to investigate their effect on the formability of CP-Ti-Gr2 foils. Initially, the properties of the received material are tested along different directions through the uniaxial tensile test, followed by furnace annealing to produce equiaxed recrystallized grains and reduce the anisotropy of the foils. Subsequently, the specimens are heat-treated at different temperatures to generate a wide spectrum of grain sizes. Through extensive μISF experiments, it was established that higher annealing temperature and increase in grain size assisted in improving the ductility of the foils, leading to enhanced formability. Therefore, the combined effect of the grain size and step depth on the formability of the components is investigated. A relationship between formability and t/d ratio was established and its critical value was obtained. Interesting observations, contrary to those in macro-ISF process were observed, e.g. higher step depth in μISF helped in improving the formability of the micro-parts. The results were confirmed by measuring the forming forces during the process, and it presented a strong correlation with the yield stress values, further correlated with varying grain sizes of the foil. This work could pave the way for designing the μISF process parameters considering the size-effects at micro-scale deformation, through optimum t/d ratio, for maximizing the formability.
{"title":"An investigation of the formability of ultra-thin CP-Ti-Gr2 foils considering thickness-to-grain-size effects under controlled heat treatment in μ-ISF","authors":"Mainak Pal, Anupam Agrawal, Chandrakant K. Nirala","doi":"10.1016/j.jmapro.2024.09.107","DOIUrl":"10.1016/j.jmapro.2024.09.107","url":null,"abstract":"<div><div>Micro-forming is an emerging micro-manufacturing process for the fabrication of miniature parts/components made of ultra-thin sheets (foils), forged billets, rods, etc. Achieving high formability in the micro-incremental sheet forming (μISF) process is difficult due to the size-effect and non-optimal selection of process parameters viz. step depth (∆z). The major sources of size-effects are pure volume source, surface-to-volume ratio, thickness-to-grain-size (t/d ratio), surface structure scalability, etc. In the micro-scale processes, studying the grain size of the material is crucial to understand the deformation behaviour. Additionally, the anisotropy is very prominent in thin foils and affects the micro-forming process adversely. In the present work, the intrinsic anisotropy of the foils is minimized through controlled heat treatment, and varying grain sizes, having different microstructures, are generated to investigate their effect on the formability of CP-Ti-Gr2 foils. Initially, the properties of the received material are tested along different directions through the uniaxial tensile test, followed by furnace annealing to produce equiaxed recrystallized grains and reduce the anisotropy of the foils. Subsequently, the specimens are heat-treated at different temperatures to generate a wide spectrum of grain sizes. Through extensive μISF experiments, it was established that higher annealing temperature and increase in grain size assisted in improving the ductility of the foils, leading to enhanced formability. Therefore, the combined effect of the grain size and step depth on the formability of the components is investigated. A relationship between formability and t/d ratio was established and its critical value was obtained. Interesting observations, contrary to those in macro-ISF process were observed, e.g. higher step depth in μISF helped in improving the formability of the micro-parts. The results were confirmed by measuring the forming forces during the process, and it presented a strong correlation with the yield stress values, further correlated with varying grain sizes of the foil. This work could pave the way for designing the μISF process parameters considering the size-effects at micro-scale deformation, through optimum t/d ratio, for maximizing the formability.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1202-1218"},"PeriodicalIF":6.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Welding defect prediction is the foundation for ensuring welding quality in gas tungsten arc welding (GTAW). In the prediction process, method based on molten pool vision is the most effective. Since the classification of molten pool defects relies on a substantial volume of labeled data, it is challenging for the models to be applied industrially. This paper presents an algorithm, FS-Classifier, that can achieve high prediction accuracy based on a limited amount of labeled data. The FS-Classifier comprises two stages: Firstly, an unsupervised training approach named RaP is designed to pre-train the feature extractor using extensive unlabeled daily datasets. The RaP consists of a rotation angle prediction task and a position prediction task, which ensure that the network focuses on salient features and precise elements, respectively. Secondly, the support vectors constructed from limited labeled data are used for the feature classifier. The input data is classified to certain class by computing its distances to support vector. The model achieves an accuracy of 94.5 % on the private dataset and 92.8 % on the public dataset for the six classes of defects using 5 % of labeled data volume. In addition, comparative experiments show that our method only requires 5 % of labeled data to achieve accuracy comparable to traditional supervised learning methods. The proposed algorithm addresses the issue of relying on a substantial amount of labeled data in welding process defect classification.
{"title":"A defect classification algorithm for gas tungsten arc welding process based on unsupervised learning and few-shot learning strategy","authors":"Qiang Liu , Runquan Xiao , Yuqing Xu , Jingyuan Xu , Shanben Chen","doi":"10.1016/j.jmapro.2024.09.084","DOIUrl":"10.1016/j.jmapro.2024.09.084","url":null,"abstract":"<div><div>Welding defect prediction is the foundation for ensuring welding quality in gas tungsten arc welding (GTAW). In the prediction process, method based on molten pool vision is the most effective. Since the classification of molten pool defects relies on a substantial volume of labeled data, it is challenging for the models to be applied industrially. This paper presents an algorithm, FS-Classifier, that can achieve high prediction accuracy based on a limited amount of labeled data. The FS-Classifier comprises two stages: Firstly, an unsupervised training approach named RaP is designed to pre-train the feature extractor using extensive unlabeled daily datasets. The RaP consists of a rotation angle prediction task and a position prediction task, which ensure that the network focuses on salient features and precise elements, respectively. Secondly, the support vectors constructed from limited labeled data are used for the feature classifier. The input data is classified to certain class by computing its distances to support vector. The model achieves an accuracy of 94.5 % on the private dataset and 92.8 % on the public dataset for the six classes of defects using 5 % of labeled data volume. In addition, comparative experiments show that our method only requires 5 % of labeled data to achieve accuracy comparable to traditional supervised learning methods. The proposed algorithm addresses the issue of relying on a substantial amount of labeled data in welding process defect classification.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1219-1229"},"PeriodicalIF":6.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmapro.2024.09.101
S. Patel, Y. Liu, Z. Siddique, I. Ghamarian
Additive manufacturing (AM) of metals has gained massive attention due to its salient features, such as a tool-free process, near-net shape product development, less fabrication time, and no restriction on product size. This paper provides a brief overview of common metal AM processes, including powder bed fusion, binder jetting, directed energy deposition, and sheet lamination. The advantages of each metal AM technology and their limitations are compared and addressed with examples. Critical steps to ensure the successful 3D printing of metal structures are discussed for each metal AM approach. The effect of each processing parameter is critically analyzed to enhance fabrication characteristics. The metal AM mechanisms, optimization of processing parameters, powder preparation techniques and their effects on the powder morphology, and applications of metal AM are discussed.
金属快速成型制造（AM）具有无需工具、产品开发接近净形、制造时间短、不受产品尺寸限制等显著特点，因而受到广泛关注。本文简要介绍了常见的金属 AM 工艺，包括粉末床熔融、粘合剂喷射、定向能沉积和薄片层压。本文通过实例对每种金属 AM 技术的优势和局限性进行了比较和论述。针对每种金属 AM 方法，讨论了确保成功 3D 打印金属结构的关键步骤。对每个加工参数的影响进行了批判性分析，以提高制造特性。讨论了金属 AM 机制、加工参数优化、粉末制备技术及其对粉末形态的影响，以及金属 AM 的应用。
{"title":"Metal additive manufacturing: Principles and applications","authors":"S. Patel, Y. Liu, Z. Siddique, I. Ghamarian","doi":"10.1016/j.jmapro.2024.09.101","DOIUrl":"10.1016/j.jmapro.2024.09.101","url":null,"abstract":"<div><div>Additive manufacturing (AM) of metals has gained massive attention due to its salient features, such as a tool-free process, near-net shape product development, less fabrication time, and no restriction on product size. This paper provides a brief overview of common metal AM processes, including powder bed fusion, binder jetting, directed energy deposition, and sheet lamination. The advantages of each metal AM technology and their limitations are compared and addressed with examples. Critical steps to ensure the successful 3D printing of metal structures are discussed for each metal AM approach. The effect of each processing parameter is critically analyzed to enhance fabrication characteristics. The metal AM mechanisms, optimization of processing parameters, powder preparation techniques and their effects on the powder morphology, and applications of metal AM are discussed.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"131 ","pages":"Pages 1179-1201"},"PeriodicalIF":6.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号