Manufacturing Letters最新文献

{"title":"Effects of Heat Exposure Duration on Human Bronchial Epithelial Cells in 3D Printed Samples","authors":"Taieba Tuba Rahman,&nbsp;Nathan Wood,&nbsp;Zhijian Pei,&nbsp;Hongmin Qin","doi":"10.1016/j.mfglet.2026.07.094","DOIUrl":"10.1016/j.mfglet.2026.07.094","url":null,"abstract":"<div><div>This paper reports an experimental study on the effects of heat exposure duration on human bronchial epithelial (HBE) cells encapsulated in 3D printed samples. Petri dishes containing the 3D printed samples were exposed to a temperature of 45 °C for three levels of exposure duration (15, 60, and 150 minutes). Microscopic imaging of the 3D-printed samples was employed to assess cell viability. The findings showed a reduction in cell viability with increasing exposure duration, suggesting that prolonged heat exposure significantly exacerbates cellular injury in HBE cells. Specifically, cell viability decreased approximately 20% when exposure duration changed from 15 to 60 minutes, and approximately 75% when exposure duration changed from 60 to 150 minutes. This study contributes to advancing the understanding of how heat exposure duration affects the respiratory system.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 806-812"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149095912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NAMRC 54 Fast-Tracked Research Papers to Journal of Manufacturing Systems and Journal of Manufacturing Processes","authors":"Xun Xu,&nbsp;Stefania Bruschi,&nbsp;Robert X. Gao","doi":"10.1016/j.mfglet.2026.07.008","DOIUrl":"10.1016/j.mfglet.2026.07.008","url":null,"abstract":"","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 6-7"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149095954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Big Data Analytics for RFID-enabled Manufacturing: A Case Study on Production Efficiency and Quality Optimization","authors":"Qiaohao Hu,&nbsp;Ray Y. Zhong","doi":"10.1016/j.mfglet.2026.07.014","DOIUrl":"10.1016/j.mfglet.2026.07.014","url":null,"abstract":"<div><div>This study presents a comprehensive big data analytics approach for processing and analyzing radio frequency identification (RFID) data in a smart manufacturing environment. Using a dataset containing 413,472 records of manufacturing operations, we extract actionable insights to improve production efficiency and product quality. Our methodology includes data preprocessing, cluster analysis, multi-dimensional worker efficiency evaluation, and machine learning-based quality prediction. The results reveal distinct clusters of manufacturing processes with varying levels of complexity, significant correlations between process sequences and equipment utilization, and a robust framework for identifying high-performing workers. Furthermore, our machine learning quality prediction system achieves an accuracy of 86.4%. These findings offer manufacturers data-driven strategies for optimizing worker assignments, process sequencing, and quality control in RFID-enabled environments. The results reveal five distinct processing clusters with varying complexity levels and quality characteristics. Comprehensive temporal analysis uncovered significant shift-based quality differences (ANOVA: F=8.55, p&lt;0.001), with Night Shift achieving the highest quality (99.29%) and Day Shift the lowest (99.16%). A systematic weekly quality decline trend was identified (slope=-0.000833/week, R²=0.824, p&lt;0.001), suggesting equipment degradation or material variation factors. Hourly analysis revealed peak quality at 05:00 (99.58%) and lowest at 07:00 (98.92%), corresponding to shift transition periods. Within-shift fatigue analysis showed minimal degradation, with only Night Shift exhibiting a slight decline (-0.15%).</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 51-57"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149095960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Fuzzy Decision-Making Framework for Optimizing Process Parameters in Laser Powder Directed Energy Deposition Additive Manufacturing","authors":"Amir Shakibi,&nbsp;Amir Yah,&nbsp;Yue Zhou","doi":"10.1016/j.mfglet.2026.07.076","DOIUrl":"10.1016/j.mfglet.2026.07.076","url":null,"abstract":"<div><div>This study presents a fuzzy multi-criteria framework for evaluating single-track quality in Laser Powder Directed Energy Deposition (LP-DED). The approach integrates three key geometric descriptors, including symmetry index, wetting angle, and dilution ratio, into a unified Triangular Fuzzy Number (TFN)-based TOPSIS model to capture the nonlinear relationships among process parameters and bead geometry. Twenty-seven single tracks were fabricated full factorial experiment design, varying laser power, scan speed, and powder feed rate. Optical microscopy measurements were used to quantify geometric metrics, and fuzzy normalization was applied to rank parameter sets by a closeness coefficient (C*) representing overall deposition quality. The fuzzy-based ranking effectively distinguished stable from unstable deposition regimes: high-ranked samples (C*&gt;0.8) exhibited well-balanced bead geometry and moderate wetting angles, while low-ranked samples (C*&lt;0.5) showed asymmetric melt pools and excessive dilution. Verification prints using the top-, mid-, and low-ranked parameter sets confirmed this trend, with roughness and porosity measurements. The insights gained from this work can guide adaptive process optimization, improve build reliability, and support the development of intelligent, data-driven control strategies for next-generation metal additive manufacturing systems.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 644-653"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149096157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Quality and Integrity in QCW Fiber Laser Welding of Tab to Busbar for EV Battery Interconnects","authors":"Rajesh Gorai,&nbsp;Ramesh Singh","doi":"10.1016/j.mfglet.2026.07.048","DOIUrl":"10.1016/j.mfglet.2026.07.048","url":null,"abstract":"<div><div>Quasi-continuous wave (QCW) fiber laser welding has emerged as a promising technique for battery tab-to-busbar joining due to its ability to deliver high peak power in pulsed mode with flexible control over energy distribution. In spite of these benefits, there is a limited understanding of how QCW laser process parameters, particularly pulse frequency and scan speed, influence weld quality, bond failure load, and electrical performance in tab-to-busbar interconnects. Therefore, this paper is focused on the effects of laser frequency (25-100 Hz) and scan speed (1-7 mm/sec) on the weld quality and reliability in terms of bond failure load, contact resistance, and weld morphology of Ni-plated Cu (Ni-plated [Cu]) busbar to stainless steel–copper–stainless steel (SS-Cu-SS) sandwich tab joint. A parametric study revealed that joint quality is primarily governed by pulse overlap and linear energy density (LED). The study reports that a minimum overlap of 10% is required for bonding, while an optimal 20–60% overlap and an LED of 20–40 J/mm produce the highest bond failure loads (<span><math><mrow><mo>&gt;</mo><mn>500</mn></mrow></math></span>N) and the lowest contact resistance (<span><math><mrow><mo>&lt;</mo><mn>160</mn></mrow></math></span> <span><math><mrow><mi>μ</mi><mi>Ω</mi></mrow></math></span>). A 43.6% reduction in contact resistance was achieved by increasing the frequency from 25 Hz to 75 Hz at a scan speed of 7 mm/s, corresponding to an improvement in overlap. Stable weld widths are obtained (210–240 <span><math><mrow><mi>μ</mi></mrow></math></span>m) within the optimal overlap range; however, a jump in width to 260–275 <span><math><mrow><mi>μ</mi></mrow></math></span>m occurs under extreme parameter combinations. Higher pulse frequencies and slower scan speeds improve heat input and material transport, increasing microhardness; the maximum value (258 <span><math><mrow><msub><mrow><mi>HV</mi></mrow><mrow><mn>0.05</mn></mrow></msub></mrow></math></span>) was attained at 50 Hz and 3 mm/s. The findings demonstrate that obtaining low-resistance and high-strength welds in battery interconnects requires ideal overlap and linear energy density.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 377-386"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149096407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of Actuation Waveforms for Precision Control of PEDOT:PSS Droplet Formation in Inkjet Printing","authors":"Tiansong Wang,&nbsp;Yuan-Shin Lee,&nbsp;Jingyan Dong","doi":"10.1016/j.mfglet.2026.07.039","DOIUrl":"10.1016/j.mfglet.2026.07.039","url":null,"abstract":"<div><div>Inkjet printing offers a scalable and cost-effective approach for the maskless fabrication of high-resolution device patterns for flexible electronics. Controlling droplet size for various functional inks become a critical task to fully utilize the fabrication capability of the inkjet printing. In this work, we investigate the effect of the waveform design on controlling the droplet formation using PEDOT:PSS ink. Three waveform types: unipolar, sinusoidal, and bipolar, were examined to modulate pressure dynamics within the printing nozzle. By tuning actuation voltage and timing parameters, we successfully reduced the printed droplet diameters from 60 μm to 30.28 μm for a printing nozzle with 30 μm nozzle orifice, approaching the physical limit from the nozzle size. Through detailed parametric optimization, we identified critical time-voltage regimes for each waveform, revealing the physical principles that govern ink chamber dynamics and droplet generation. These results and findings establish a foundation towards waveform-driven resolution enhancement in inkjet printing and contribute to the broader applications of high-precision additive fabrication for next-generation electronic devices.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 303-310"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149096530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combined effect of jet overlap and its gradual variation in abrasive waterjet milling of non-flat cavities on Aluminum 7075-T6 alloy","authors":"Saurabh Gharat,&nbsp;D.S. Srinivasu","doi":"10.1016/j.mfglet.2026.07.035","DOIUrl":"10.1016/j.mfglet.2026.07.035","url":null,"abstract":"<div><div>Generation of various forms of non-flat surfaces in advanced engineering materials (AEMs) is required for realizing a variety of functionalities across aerospace, automotive, biomedical, and defence industries.<!--> <!-->The conventional manufacturing process comes with limitations, such as high tool wear, poor machinability, thermal damage, and increased costs. Although abrasive waterjet machining (AWJM) is apt in this context, generating near-net shape non-flat cavities pose significant challenges due to the stochastic nature of the high-velocity aggressive jet. On the other hand, the majority of the literature reported on AWJM is related to through-cutting; although some studies are reported on flat milled surfaces, the research on the generation of non-flat surfaces is very limited. Among the many approaches available for the generation of non-flat surfaces, changing the jet overlap is one of the unexplored areas due to its complexity in understanding the underlying physical phenomena. Considering the ease with which the jet overlap can be changed, this study investigates the combined effect of jet overlap and its gradual variation direction on the generation of non-flat cavities in aluminium 7075-T6 alloy. For this purpose, an attempt is made initially to understand the effect of jet overlap on the erosion behaviour through CFD simulations. Furthermore, the gradual variation in the direction of the jet overlap (GVJO) prediction model is developed that helps in selecting (i) the overlap percentage, and (ii) the gradual variation in the direction of jet overlap, for the desired non-flat cavities. Following this, the jet paths are generated for the jet overlap sequence predicted by the GVJO model, featuring gradual variations in (a) the descending jet overlap, and (b) the ascending jet overlap. The combined effect of the jet-overlapping sequence predicted by the GVJO model and its placement direction is analysed across ten case studies. Finally, the milling experimental results demonstrated that a gradual variation in jet overlap alters the depth according to the desired non-flat cavities. The non-flat cavities generated by the jet path with the overlap variation in the descending manner perform well with a mean root mean square error (RMSE) of 233 µm against its counterpart that comes with a mean RMSE of 426 µm. The jet path with an ascending jet overlap features less surface roughness compared to its counterpart, with a mean surface roughness of 16 μm. The effective milling of non-flat cavities clearly illustrates the significance of variation in jet overlap, its gradual variation in the jet path, and<!--> <!-->the GVJO prediction model. Ultimately, highlights the<!--> <!-->capabilities of AWJM<!--> <!-->for near-net-shape<!--> <!-->manufacturing of AEMs.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 259-270"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149096527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tripod Micro-Positioning System with Compound Flexure Hinges and a Spherical Pivot","authors":"Soon Hwan Kwon,&nbsp;Jong Phil Choi,&nbsp;Young Ho Seo,&nbsp;Byeong Hee Kim","doi":"10.1016/j.mfglet.2026.07.028","DOIUrl":"10.1016/j.mfglet.2026.07.028","url":null,"abstract":"<div><div>This study presents the design, modeling, and experimental validation of a flexure-hinged tripod micro-positioning stage actuated by Pb(ZrTi)O₃ PZT stacks. The stage integrates a beam-type flexure for z-motion, a wide-range flexure for tilt compliance, and a spherical flexure pivot that maintains a fixed geometric origin during motion. This configuration achieves decoupled translation and rotation within a compact SUS304 structure while eliminating mechanical backlash. Finite element analyses confirmed elastic behavior with stresses below 65% of yield and independent hinge deformation. The fabricated prototype, evaluated via laser vibrometer, exhibited a maximum vertical stroke of 13.9 µm at 900 V, showing high linearity and repeatability. These results demonstrate the system’s suitability for submicron precision alignment, micro-assembly, and scanning applications.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 188-194"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149096612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additive Manufacturing of Nanoparticle-enhanced Aluminum Alloy 2024","authors":"Tianqi Zheng,&nbsp;Guan-Cheng Chen,&nbsp;Alexander Killips,&nbsp;Mengchen Li,&nbsp;Bingbing Li,&nbsp;Yinmin Morris Wang,&nbsp;Xiaochun Li","doi":"10.1016/j.mfglet.2026.07.079","DOIUrl":"10.1016/j.mfglet.2026.07.079","url":null,"abstract":"<div><div>Laser Powder Bed Fusion (LPBF) of high-strength aluminum alloys such as AA2024 has long been challenged by hot cracking and poor thermal stability. In this study, we demonstrate that nanoparticle-enabled additive manufacturing using nano-treated AA2024 with nanoparticles (designated as 2024NT) effectively overcomes these limitations. By optimizing LPBF parameters and employing a chessboard scanning strategy, crack-free 2024NT samples with ultra-low porosity (&lt;0.5%) were successfully fabricated. Compared with conventional wrought 2024-T4, the LPBF-processed 2024NT exhibits significantly refined microstructures, enhanced precipitation behavior, and superior mechanical performance. Specifically, the 2024NT-T4 alloy demonstrates a 34% increase in yield strength and a 17% improvement in ultimate tensile strength at room temperature, while maintaining moderate ductility. These improvements are discussed in terms of combined grain refinement and age-hardening, supported by literature showing that ceramic nanoparticle/dispersoid additions can promote finer strengthening microstructures and impede precipitates coarsening during thermal exposure. This work provides a viable pathway for enabling high-strength, thermally stable AA2024 components via additive manufacturing.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 672-680"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149095904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Evaluation of Task-specific Machine Learning and Foundation Models for Melt Pool Anomaly Detection in Laser Powder Bed Fusion","authors":"Gisuk Hong,&nbsp;Sebastien Philomin,&nbsp;Nowrin Akter Surovi,&nbsp;Hyunbo Cho,&nbsp;Yan Lu","doi":"10.1016/j.mfglet.2026.07.087","DOIUrl":"10.1016/j.mfglet.2026.07.087","url":null,"abstract":"<div><div>Foundation models enable low-cost development and operator-friendly deployment of online quality inspections in manufacturing. However, whether foundation models pre-trained can effectively adapted for specialized industrial process monitoring remains insufficiently understood, particularly regarding fault detection effectiveness, adaptation efforts, and computational trade-offs compared to task-specific machine learning models. This paper presents a systematic comparative benchmark study using a reference framework that models learning and adaptation processes. Both task-specific machine learning and foundation model-based approaches are aligned along common spectrums of data availability and adaptation mechanisms and evaluated with uniform metrics. Through a case study of melt pool monitoring in laser powder bed fusion additive manufacturing, we compare six learning strategies spanning unsupervised, semi-supervised, supervised, zero-shot, few-shot, and fine-tuned foundation model-based approaches. The analysis compares performance trade-offs based on data availability for adaptation, highlighting when adapted foundation models become competitive against task-specific learnings. In addition, this work evaluates industrial anomaly detection approaches for computational constraints and resource requirements. The systematic methodology with an example can guide the industry to select the most appropriated process anomaly detection methods for their applications, which balances accuracy, data efficiency, and computational feasibility in resource-constrained manufacturing environments.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"49 ","pages":"Pages 730-741"},"PeriodicalIF":2.8,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149095905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}