Pub Date : 2026-04-01Epub Date: 2026-02-21DOI: 10.1016/j.addlet.2026.100370
Joachim C.G. Eng , Louis N.S. Chiu , Aijun Huang , Bernard Rolfe , Wenyi Yan
Laser-directed energy deposition (L-DED) filling repair is often compromised by printing defects like cracking induced by excessive thermal residual stresses. Optimising process parameters is challenging, as complex thermal histories make trial-and-error costly and simulations computationally inefficient. To bridge this, a finite element (FE)-driven machine learning (ML) framework was developed to optimise multi-layer multi-track filling repair bulk quality. The methodology ensures consistent fill volume by enforcing nominal single-track dimensions. A thermomechanically validated FE model generated training data via design of experiment (DoE) strategies. Among evaluated algorithms, the multilayer perceptron (MLP) achieved superior accuracy (R2 = 0.98, NRMSE = 2.7 %) as an efficient surrogate. Integrated response surface methodology (RSM) highlighted a critical trade-off, revealing moderate energy density as the optimal compromise for balancing residual stress and distortion. Furthermore, parameter influence analysis identified scan speed as the dominant control variable, closely followed by laser power and preheat temperature. Ultimately, this framework provides a robust and efficient tool for defining optimal process windows in l-DED filling repair.
{"title":"Linking process parameters to residual stress and distortion in directed energy deposition repair via machine learning and response surface methodology","authors":"Joachim C.G. Eng , Louis N.S. Chiu , Aijun Huang , Bernard Rolfe , Wenyi Yan","doi":"10.1016/j.addlet.2026.100370","DOIUrl":"10.1016/j.addlet.2026.100370","url":null,"abstract":"<div><div>Laser-directed energy deposition (L-DED) filling repair is often compromised by printing defects like cracking induced by excessive thermal residual stresses. Optimising process parameters is challenging, as complex thermal histories make trial-and-error costly and simulations computationally inefficient. To bridge this, a finite element (FE)-driven machine learning (ML) framework was developed to optimise multi-layer multi-track filling repair bulk quality. The methodology ensures consistent fill volume by enforcing nominal single-track dimensions. A thermomechanically validated FE model generated training data via design of experiment (DoE) strategies. Among evaluated algorithms, the multilayer perceptron (MLP) achieved superior accuracy (R<sup>2</sup> = 0.98, NRMSE = 2.7 %) as an efficient surrogate. Integrated response surface methodology (RSM) highlighted a critical trade-off, revealing moderate energy density as the optimal compromise for balancing residual stress and distortion. Furthermore, parameter influence analysis identified scan speed as the dominant control variable, closely followed by laser power and preheat temperature. Ultimately, this framework provides a robust and efficient tool for defining optimal process windows in <span>l</span>-DED filling repair.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100370"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-02DOI: 10.1016/j.addlet.2026.100362
Jesus Rivas , Cesar Terrazas , Hugo Estrada , Francisco Medina , James P. Carney
Laser powder bed fusion of metals (PBF-LB/M) remains prone to process-induced porosity, and practical tools that connect scan behavior to defect formation are still limited. In this study, we present a framework that predicts porosity from scan data acquired on a commercial PBF-LB/M system using an embedded high-speed scan acquisition device. The device records scanning position, time, and laser power at high temporal resolution, enabling reconstruction of layer-wise exposure paths that are normally inaccessible to users. From these data, we derive porosity-prone “hotspot” regions based on high linear energy input, energy input gradients, and deceleration or acceleration events along the scan path. Ground-truth porosity is obtained from X-ray Computed Tomography (XCT) of a compact qualification artifact containing multiple geometries, including lattice structures. Across the machine learning evaluated models, LSBoost provides the best overall performance when predicting total pore counts per layer with a Mean Absolute Error (MAE) ≈ 7.29. Prediction of larger pores with equivalent diameters greater than 0.100 mm was slightly more accurate (MAE = 4.747), indicating stronger correlation for critical part anomalies. However, porosity outliers tend to be underestimated, highlighting both the need for improved calibration and the benefit of additional in situ process signals that capture interactions with other process variables such as powder or gas flow. Overall, the results demonstrate that scan-derived hotspot features, combined with machine learning, are a viable basis for in situ identification and prediction of porosity-prone layers in PBF-LB/M.
{"title":"Predicting porosity in laser powder bed fusion of metals (PBF-LB/M) using scanning data and machine learning","authors":"Jesus Rivas , Cesar Terrazas , Hugo Estrada , Francisco Medina , James P. Carney","doi":"10.1016/j.addlet.2026.100362","DOIUrl":"10.1016/j.addlet.2026.100362","url":null,"abstract":"<div><div>Laser powder bed fusion of metals (PBF-LB/M) remains prone to process-induced porosity, and practical tools that connect scan behavior to defect formation are still limited. In this study, we present a framework that predicts porosity from scan data acquired on a commercial PBF-LB/M system using an embedded high-speed scan acquisition device. The device records scanning position, time, and laser power at high temporal resolution, enabling reconstruction of layer-wise exposure paths that are normally inaccessible to users. From these data, we derive porosity-prone “hotspot” regions based on high linear energy input, energy input gradients, and deceleration or acceleration events along the scan path. Ground-truth porosity is obtained from X-ray Computed Tomography (XCT) of a compact qualification artifact containing multiple geometries, including lattice structures. Across the machine learning evaluated models, LSBoost provides the best overall performance when predicting total pore counts per layer with a Mean Absolute Error (MAE) ≈ 7.29. Prediction of larger pores with equivalent diameters greater than 0.100 mm was slightly more accurate (MAE = 4.747), indicating stronger correlation for critical part anomalies. However, porosity outliers tend to be underestimated, highlighting both the need for improved calibration and the benefit of additional in situ process signals that capture interactions with other process variables such as powder or gas flow. Overall, the results demonstrate that scan-derived hotspot features, combined with machine learning, are a viable basis for in situ identification and prediction of porosity-prone layers in PBF-LB/M.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100362"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147385027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-21DOI: 10.1016/j.addlet.2026.100359
Jixuan Dong , Hasan Al Jame , Zachary C. Cordero , S. Mohadeseh Taheri-Mousavi
Additive manufacturing enables net-shaped compositionally graded components that satisfy conflicting property requirements through spatial variations in alloy chemistry and microstructure. Although current path-planning methods for compositionally graded alloys emphasize avoiding deleterious phases, property evolution along compositional gradients is equally important because abrupt property changes can degrade structural integrity. In light of this concern, this study integrates high-throughput calculation of phase diagrams (CALPHAD)-based integrated computational materials science (ICME) simulations with variance-based global sensitivity analysis to introduce a framework for designing smoother property transitions. Thermophysical and mechanical properties along binary gradients between pairs of Inconel 718, Monel K-500, and Invar 36 were computed, revealing strongly nonlinear property transitions. Sensitivity analysis identified aluminum as a key driver of variability in thermal expansion coefficient along a transition, and this variability was reduced by tailoring the compositions in the terminal alloys. This framework can be used for similar identification and and tailoring of various property variability to achieve optimal component-level performance.
{"title":"Computational predictions of complex property trajectories in compositionally graded alloys","authors":"Jixuan Dong , Hasan Al Jame , Zachary C. Cordero , S. Mohadeseh Taheri-Mousavi","doi":"10.1016/j.addlet.2026.100359","DOIUrl":"10.1016/j.addlet.2026.100359","url":null,"abstract":"<div><div>Additive manufacturing enables net-shaped compositionally graded components that satisfy conflicting property requirements through spatial variations in alloy chemistry and microstructure. Although current path-planning methods for compositionally graded alloys emphasize avoiding deleterious phases, property evolution along compositional gradients is equally important because abrupt property changes can degrade structural integrity. In light of this concern, this study integrates high-throughput calculation of phase diagrams (CALPHAD)-based integrated computational materials science (ICME) simulations with variance-based global sensitivity analysis to introduce a framework for designing smoother property transitions. Thermophysical and mechanical properties along binary gradients between pairs of Inconel 718, Monel K-500, and Invar 36 were computed, revealing strongly nonlinear property transitions. Sensitivity analysis identified aluminum as a key driver of variability in thermal expansion coefficient along a transition, and this variability was reduced by tailoring the compositions in the terminal alloys. This framework can be used for similar identification and and tailoring of various property variability to achieve optimal component-level performance.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100359"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-03-06DOI: 10.1016/j.addlet.2026.100372
Michèle Bréhier , Daniel Weisz-Patrault , Christophe Tournier
Directed energy deposition additive manufacturing is a versatile technique for fabricating complex geometries, where precise control of process parameters is crucial for tailoring microstructure and part properties. Microstructure control strategies usually involve variation of material composition (i.e., functionally graded materials) or interlayer time delay. However, the obtained microstructures are usually uniform in the print direction and exhibit sharp transitions from one layer to the next in the build direction. This paper targets continuous microstructural variation by exploiting active cooling strategies to control cooling conditions. To do so, the scanning speed is continuously varied, necessitating accommodating the bead size variations with non-standard trajectory generation based on a phenomenological law. The proposed strategy is demonstrated on thin-wall structures made of IN718 using a powder-based laser directed energy deposition. The results reveal a continuous microstructural transition along the print direction, characterized by two distinct microstructural regimes with markedly different morphological features and crystallographic textures. This demonstrates the capability of scanning speed modulation to engineer heterogeneous microstructures within a single component, offering insights into tailoring material properties for specific engineering applications.
{"title":"Continuous microstructure variations with graded properties in directed energy deposition","authors":"Michèle Bréhier , Daniel Weisz-Patrault , Christophe Tournier","doi":"10.1016/j.addlet.2026.100372","DOIUrl":"10.1016/j.addlet.2026.100372","url":null,"abstract":"<div><div>Directed energy deposition additive manufacturing is a versatile technique for fabricating complex geometries, where precise control of process parameters is crucial for tailoring microstructure and part properties. Microstructure control strategies usually involve variation of material composition (i.e., functionally graded materials) or interlayer time delay. However, the obtained microstructures are usually uniform in the print direction and exhibit sharp transitions from one layer to the next in the build direction. This paper targets continuous microstructural variation by exploiting active cooling strategies to control cooling conditions. To do so, the scanning speed is continuously varied, necessitating accommodating the bead size variations with non-standard trajectory generation based on a phenomenological law. The proposed strategy is demonstrated on thin-wall structures made of IN718 using a powder-based laser directed energy deposition. The results reveal a continuous microstructural transition along the print direction, characterized by two distinct microstructural regimes with markedly different morphological features and crystallographic textures. This demonstrates the capability of scanning speed modulation to engineer heterogeneous microstructures within a single component, offering insights into tailoring material properties for specific engineering applications.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100372"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147385001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-10DOI: 10.1016/j.addlet.2026.100364
Shramana Ghosh , Miguel Hoffmann , Lauren Heinrich , Kenton B. Fillingim , Joshua Vaughan , Brian K. Post , Thomas Feldhausen
This article introduces the Future Foundries platform developed at Oak Ridge National Laboratory, a first-generation research system designed to demonstrate convergent manufacturing. Convergent manufacturing brings together additive, subtractive, and transformative processes in a digitally interconnected environment to enable end-to-end production workflows. By linking traditionally discrete steps, convergent platforms accelerate production, improve repeatability, and support high-mix, low-volume manufacturing.
The Future Foundries platform exemplifies this vision in practice by combining four modular, vendor-agnostic process cells that include robotic WAAM, induction heating, optical metrology, and machining, coordinated through an automated pallet handler and a ROS 2-based digital thread. This architecture provides the flexibility and scalability needed for agile production in small and medium-sized manufacturing enterprises and for field deployable manufacturing.
Two case studies illustrate the platform’s capabilities. The first presents an integrated workflow for fabricating, transforming, and repairing critical replacement components, showing how consolidated thermal, additive, inspection, and machining operations reduce manual part handling and streamline process flow. The second case study highlights coordinated multi-part production enabled by automated pallet logistics and multi-cell scheduling. Together, these examples showcase convergent manufacturing as a practical and scalable strategy for strengthening domestic casting and forging capacity, improving supply-chain resilience, and enabling rapid, adaptable production of mission-critical components.
{"title":"Future foundries: A convergent manufacturing platform","authors":"Shramana Ghosh , Miguel Hoffmann , Lauren Heinrich , Kenton B. Fillingim , Joshua Vaughan , Brian K. Post , Thomas Feldhausen","doi":"10.1016/j.addlet.2026.100364","DOIUrl":"10.1016/j.addlet.2026.100364","url":null,"abstract":"<div><div>This article introduces the Future Foundries platform developed at Oak Ridge National Laboratory, a first-generation research system designed to demonstrate convergent manufacturing. Convergent manufacturing brings together additive, subtractive, and transformative processes in a digitally interconnected environment to enable end-to-end production workflows. By linking traditionally discrete steps, convergent platforms accelerate production, improve repeatability, and support high-mix, low-volume manufacturing.</div><div>The Future Foundries platform exemplifies this vision in practice by combining four modular, vendor-agnostic process cells that include robotic WAAM, induction heating, optical metrology, and machining, coordinated through an automated pallet handler and a ROS 2-based digital thread. This architecture provides the flexibility and scalability needed for agile production in small and medium-sized manufacturing enterprises and for field deployable manufacturing.</div><div>Two case studies illustrate the platform’s capabilities. The first presents an integrated workflow for fabricating, transforming, and repairing critical replacement components, showing how consolidated thermal, additive, inspection, and machining operations reduce manual part handling and streamline process flow. The second case study highlights coordinated multi-part production enabled by automated pallet logistics and multi-cell scheduling. Together, these examples showcase convergent manufacturing as a practical and scalable strategy for strengthening domestic casting and forging capacity, improving supply-chain resilience, and enabling rapid, adaptable production of mission-critical components.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100364"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-24DOI: 10.1016/j.addlet.2026.100367
Ian Y. Ho , Jacob Viar , Hutchison Peter , Henry Claesson , Christopher Williams
Direct fabrication of multifunctional, high-performance components integrating structural dielectric and conductive materials remains a key challenge in advanced manufacturing. Additive manufacturing (AM) enables embedding functional elements layer-by-layer into structural parts. Hybrid material extrusion (MEX) systems have combined thermal reaction bonding (MEX-TRB, or fused filament fabrication, FFF) and chemical reaction bonding (MEX-CRB, or direct ink writing, DIW) modalities within the same system to directly produce multifunctional parts. However, these systems have been limited to depositing conductive traces within commodity polymers (e.g., PLA, ABS, PETG) at ambient conditions to prevent premature ink curing. These polymers lack the thermal stability to withstand high-performance ink sintering temperatures (often >250 °C), limiting conductivity of the dispensed functional inks and resulting applications.
This work introduces a novel hybrid MEX-CRB/MEX-TRB system with an actively cooled MEX-CRB head to prevent ink curing while operating in chamber temperatures up to 110 °C, enabling the printing of high-performance polymers. In-situ characterization using embedded thermocouples confirmed that the cooling system maintains ink below critical curing thresholds. Conductivity measurements demonstrated successful in-situ sintering and conductive network formation of silver conductive traces within the heated chamber. Polyphenylene sulfide (PPS) parts with embedded silver traces were fabricated, leveraging the chamber for both polymer printing and trace sintering. Compared to traditional hybrid approaches requiring part shuttling between modalities, this integrated system reduces interlayer cooling and improves polymer interlayer adhesion. These results show that the high-temperature hybrid MEX system effectively balances conflicting thermal requirements of high-performance polymers and conductive inks, enabling efficient multimodality printing for advanced electrical applications.
{"title":"Printing multifunctional high-performance polymer parts via the hybridization of high temperature material extrusion thermal and chemical reactive bonding","authors":"Ian Y. Ho , Jacob Viar , Hutchison Peter , Henry Claesson , Christopher Williams","doi":"10.1016/j.addlet.2026.100367","DOIUrl":"10.1016/j.addlet.2026.100367","url":null,"abstract":"<div><div>Direct fabrication of multifunctional, high-performance components integrating structural dielectric and conductive materials remains a key challenge in advanced manufacturing. Additive manufacturing (AM) enables embedding functional elements layer-by-layer into structural parts. Hybrid material extrusion (MEX) systems have combined thermal reaction bonding (MEX-TRB, or fused filament fabrication, FFF) and chemical reaction bonding (MEX-CRB, or direct ink writing, DIW) modalities within the same system to directly produce multifunctional parts. However, these systems have been limited to depositing conductive traces within commodity polymers (e.g., PLA, ABS, PETG) at ambient conditions to prevent premature ink curing. These polymers lack the thermal stability to withstand high-performance ink sintering temperatures (often >250 °C), limiting conductivity of the dispensed functional inks and resulting applications.</div><div>This work introduces a novel hybrid MEX-CRB/MEX-TRB system with an actively cooled MEX-CRB head to prevent ink curing while operating in chamber temperatures up to 110 °C, enabling the printing of high-performance polymers. In-situ characterization using embedded thermocouples confirmed that the cooling system maintains ink below critical curing thresholds. Conductivity measurements demonstrated successful in-situ sintering and conductive network formation of silver conductive traces within the heated chamber. Polyphenylene sulfide (PPS) parts with embedded silver traces were fabricated, leveraging the chamber for both polymer printing and trace sintering. Compared to traditional hybrid approaches requiring part shuttling between modalities, this integrated system reduces interlayer cooling and improves polymer interlayer adhesion. These results show that the high-temperature hybrid MEX system effectively balances conflicting thermal requirements of high-performance polymers and conductive inks, enabling efficient multimodality printing for advanced electrical applications.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100367"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fused filament fabrication is a popular extrusion 3D printing technology because of its affordability and accessibility. However, the approach often suffers from printing errors that result in wasted time, materials and energy. Convolutional neural networks can be trained to recognise a wide spectrum of printing anomalies from image data in real time, but past work has been limited to a few defect classifications at a time. Here, we introduce a fault detection system, designed to identify a range of errors without interrupting the printing process. Real-time detection is achieved using a pre-trained image recognition and pattern recognition convolutional neural network (CNN) with two mounted cameras on the print bed and a nozzle camera. Two CNN models are developed to classify images into common 3D printing errors for the two camera systems. The nozzle camera model achieves a high validation accuracy of 97.7%. The side camera model achieves comparable performance with a validation accuracy of 97.6%. To integrate the two CNNs into one unified system, a logic-based priority framework was used to improve reliability beyond individual model accuracies by resolving conflicting predictions and leveraging complementary viewing angles from both camera types to detect a broader range of defects. The data fusion framework identifies 12 common errors and has significantly improved the robustness of error classification, in-situ and in real-time, with inference times as small as 220 milliseconds. The results demonstrate the feasibility of a robust multi-input fault detection system to advance the reliability of extrusion 3D printing.
{"title":"Multi-camera fault detection in fused filament fabrication printing","authors":"Shanthalakshmi Kilambi , Aster Tournoy , Muhamad Amani , Jovana Jovanova , Baris Caglar , Kunal Masania","doi":"10.1016/j.addlet.2026.100360","DOIUrl":"10.1016/j.addlet.2026.100360","url":null,"abstract":"<div><div>Fused filament fabrication is a popular extrusion 3D printing technology because of its affordability and accessibility. However, the approach often suffers from printing errors that result in wasted time, materials and energy. Convolutional neural networks can be trained to recognise a wide spectrum of printing anomalies from image data in real time, but past work has been limited to a few defect classifications at a time. Here, we introduce a fault detection system, designed to identify a range of errors without interrupting the printing process. Real-time detection is achieved using a pre-trained image recognition and pattern recognition convolutional neural network (CNN) with two mounted cameras on the print bed and a nozzle camera. Two CNN models are developed to classify images into common 3D printing errors for the two camera systems. The nozzle camera model achieves a high validation accuracy of 97.7%. The side camera model achieves comparable performance with a validation accuracy of 97.6%. To integrate the two CNNs into one unified system, a logic-based priority framework was used to improve reliability beyond individual model accuracies by resolving conflicting predictions and leveraging complementary viewing angles from both camera types to detect a broader range of defects. The data fusion framework identifies 12 common errors and has significantly improved the robustness of error classification, in-situ and in real-time, with inference times as small as 220 milliseconds. The results demonstrate the feasibility of a robust multi-input fault detection system to advance the reliability of extrusion 3D printing.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100360"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-20DOI: 10.1016/j.addlet.2026.100368
Taiwo Martins Esan, Williams Kehinde Kupolati, Chris Ackerman
Additive Manufacturing (AM), commonly referred to as 3D printing, has emerged as a transformative technology in the construction sector, enabling unprecedented geometric freedom, automation, and material efficiency. While its adoption for structural applications has accelerated, its integration into building acoustics remains limited and fragmented. This systematic review synthesizes findings from 79 peer-reviewed studies to evaluate the current state of AM for architectural acoustic applications, with emphasis on materials, design strategies, validation methods, and implementation challenges. Four dominant constraint categories are identified: material limitations (≈38%), structural and design constraints (≈19%), modeling and prediction inaccuracies (≈16%), and acoustic performance limitations, particularly narrow operational bandwidths (≈27%). The review highlights the critical role of geometry-driven design, including acoustic metamaterials and micro-perforated panels, enabled by AM processes such as material extrusion, vat photopolymerization, and powder bed fusion. However, persistent challenges related to sustainability, process scalability, surface quality, and limited field-scale validation restrict broader adoption. Emerging solutions, including AI-assisted material formulation, generative acoustic design, and hybrid computational–experimental workflows, are identified as key enablers for progress. The findings provide actionable insights for engineers and designers seeking to deploy AM-based acoustic components in buildings and establish a roadmap for advancing scalable, sustainable, and high-performance architectural acoustics.
{"title":"Advances in Additive Manufacturing for Architectural Acoustics: Design, Materials, Validation, and Implementation Challenges in Building Construction","authors":"Taiwo Martins Esan, Williams Kehinde Kupolati, Chris Ackerman","doi":"10.1016/j.addlet.2026.100368","DOIUrl":"10.1016/j.addlet.2026.100368","url":null,"abstract":"<div><div>Additive Manufacturing (AM), commonly referred to as 3D printing, has emerged as a transformative technology in the construction sector, enabling unprecedented geometric freedom, automation, and material efficiency. While its adoption for structural applications has accelerated, its integration into building acoustics remains limited and fragmented. This systematic review synthesizes findings from 79 peer-reviewed studies to evaluate the current state of AM for architectural acoustic applications, with emphasis on materials, design strategies, validation methods, and implementation challenges. Four dominant constraint categories are identified: material limitations (≈38%), structural and design constraints (≈19%), modeling and prediction inaccuracies (≈16%), and acoustic performance limitations, particularly narrow operational bandwidths (≈27%). The review highlights the critical role of geometry-driven design, including acoustic metamaterials and micro-perforated panels, enabled by AM processes such as material extrusion, vat photopolymerization, and powder bed fusion. However, persistent challenges related to sustainability, process scalability, surface quality, and limited field-scale validation restrict broader adoption. Emerging solutions, including AI-assisted material formulation, generative acoustic design, and hybrid computational–experimental workflows, are identified as key enablers for progress. The findings provide actionable insights for engineers and designers seeking to deploy AM-based acoustic components in buildings and establish a roadmap for advancing scalable, sustainable, and high-performance architectural acoustics.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100368"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-03-03DOI: 10.1016/j.addlet.2026.100371
Diana Martins , João R. Matos , Diogo Sousa , Fernando Gomes de Almeida
Large-scale thermoplastic 3D printing is an emerging technology that enables cheaper and faster real-scale prototyping and rapid tooling. However, it still presents limitations that can lead to deformations in printed parts due to inadequate cooling conditions during the process. This study proposes COLD: a control and optimization of layer deposition system, based on temperature monitoring, to prevent print failures caused by excessive heat accumulation resulting from insufficient layer cooling time. A thermal camera was attached to a robotic printing system, and, after each layer is deposited, the average temperature of the regions where the next layer will be deposited is evaluated until it reaches a defined threshold. Conical thin wall parts were printed with and without COLD using Polypropylene 30% Glass Fiber, and the results show that it can contribute significantly to the success of large-scale additive manufacturing.
{"title":"COLD: Control and optimization of layer deposition in large-scale additive manufacturing","authors":"Diana Martins , João R. Matos , Diogo Sousa , Fernando Gomes de Almeida","doi":"10.1016/j.addlet.2026.100371","DOIUrl":"10.1016/j.addlet.2026.100371","url":null,"abstract":"<div><div>Large-scale thermoplastic 3D printing is an emerging technology that enables cheaper and faster real-scale prototyping and rapid tooling. However, it still presents limitations that can lead to deformations in printed parts due to inadequate cooling conditions during the process. This study proposes COLD: a control and optimization of layer deposition system, based on temperature monitoring, to prevent print failures caused by excessive heat accumulation resulting from insufficient layer cooling time. A thermal camera was attached to a robotic printing system, and, after each layer is deposited, the average temperature of the regions where the next layer will be deposited is evaluated until it reaches a defined threshold. Conical thin wall parts were printed with and without COLD using Polypropylene 30% Glass Fiber, and the results show that it can contribute significantly to the success of large-scale additive manufacturing.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"17 ","pages":"Article 100371"},"PeriodicalIF":4.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-13DOI: 10.1016/j.addlet.2025.100350
Ira Papamalama , Emilie Beevers , Berk Baris Celik , Michael Doppler , Selma Hansal , Brecht Van Hooreweder
This study investigates the morphological, geometrical, and mechanical characteristics of Al-Cu-Mg-Ag-Ti-B-Si-Fe aluminum alloy lattice structures fabricated via Laser Powder Bed Fusion (LPBF), with emphasis on quasi-static and fatigue mechanical performance. Using the Gibson–Ashby model as a framework, three relative lattice densities (RLDs) were examined in both as-built (AB) and Hirtisation® surface treated (HIRT) conditions. Results confirm that geometric strut waviness is inherent to the LPBF process, affecting both AB and HIRT samples. However, the Hirtisation® treatment notably reduces surface roughness and dross, enhancing fatigue life and surface uniformity. While strut length remains unchanged after post-treatment, a reduced strut diameter (thickness) alters the final density, directly impacting RLD and strength. Quasi-static tests validate the predicted strength–density relationship, with denser lattices exhibiting higher compressive strength. Fatigue testing reveals combined stretch and bending-dominated response, marked by crush bands and hybrid brittle-ductile failure mode. These findings deepen understanding of LPBF lattice structures and demonstrate the effectiveness of surface treatment in enhancing fatigue resistance and mechanical performance.
{"title":"Comparing geometry and mechanical performance of as built and Hirtisation® treated Al-Cu-Mg-Ag-Ti-B-Si-Fe rhombic dodecahedron lattices manufactured by laser powder bed fusion","authors":"Ira Papamalama , Emilie Beevers , Berk Baris Celik , Michael Doppler , Selma Hansal , Brecht Van Hooreweder","doi":"10.1016/j.addlet.2025.100350","DOIUrl":"10.1016/j.addlet.2025.100350","url":null,"abstract":"<div><div>This study investigates the morphological, geometrical, and mechanical characteristics of Al-Cu-Mg-Ag-Ti-B-Si-Fe aluminum alloy lattice structures fabricated via Laser Powder Bed Fusion (LPBF), with emphasis on quasi-static and fatigue mechanical performance. Using the Gibson–Ashby model as a framework, three relative lattice densities (RLDs) were examined in both as-built (AB) and Hirtisation® surface treated (HIRT) conditions. Results confirm that geometric strut waviness is inherent to the LPBF process, affecting both AB and HIRT samples. However, the Hirtisation® treatment notably reduces surface roughness and dross, enhancing fatigue life and surface uniformity. While strut length remains unchanged after post-treatment, a reduced strut diameter (thickness) alters the final density, directly impacting RLD and strength. Quasi-static tests validate the predicted strength–density relationship, with denser lattices exhibiting higher compressive strength. Fatigue testing reveals combined stretch and bending-dominated response, marked by crush bands and hybrid brittle-ductile failure mode. These findings deepen understanding of LPBF lattice structures and demonstrate the effectiveness of surface treatment in enhancing fatigue resistance and mechanical performance.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"16 ","pages":"Article 100350"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145798694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}