Additive manufacturing letters最新文献_第9页

On the potential of eddy current characterization of the ferritic content of recovered 316L powders after LaserPowder bed fusion fabrication 激光粉末床熔融制造后回收的 316L 粉末中铁素体含量的涡流表征潜力

Additive manufacturing letters Pub Date : 2024-04-01 DOI: 10.1016/j.addlet.2024.100207

R. Saddoud , K. Perlin , N. Sergeeva-Chollet , T. Delacroix , A. Skarlatos , J.P. Garandet

引用次数: 0

Additive manufacturing of high nitrogen austenitic steel using shell-core strategy 利用壳芯策略快速成型制造高氮奥氏体钢

Additive manufacturing letters Pub Date : 2024-03-20 DOI: 10.1016/j.addlet.2024.100205

L. Becker , F. Radtke , J. Lentz , S. Herzog , C. Broeckmann , S. Weber

{"title":"Additive manufacturing of high nitrogen austenitic steel using shell-core strategy","authors":"L. Becker , F. Radtke , J. Lentz , S. Herzog , C. Broeckmann , S. Weber","doi":"10.1016/j.addlet.2024.100205","DOIUrl":"10.1016/j.addlet.2024.100205","url":null,"abstract":"<div><p>Laser Powder Bed Fusion/Metal (PBF-LB/M) is a promising technology for industrial applications, but challenges such as long process times remain. Innovations such as the shell-core approach aim to address this by creating a dense shell around a minimally exposed powder core, significantly reducing processing times, with full densification and property adjustments achieved by subsequent hot isostatic pressing (HIP). This study focuses on the fabrication of shell-core samples using a powder mixture of austenitic steel and Si<sub>3</sub>N<sub>4</sub> to produce high nitrogen steel PBF-LB/M components, which are otherwise difficult to produce due to the limited nitrogen solubility in the melt. PBF-LB/M induces Si<sub>3</sub>N<sub>4</sub> decomposition, resulting in Si and N loss through laser-powder interaction. Si<sub>3</sub>N<sub>4</sub> particles in the still powdered regions serve as a source of N enrichment during HIP, circumventing the limitations of nitrogen solubility in the melt and exploiting the higher solubility in the solid. After HIP, energy dispersive spectrometry and electron backscatter diffraction reveal a fully austenitic matrix with Si diffusion seams mainly in non-laser-exposed areas. The Si<sub>3</sub>N<sub>4</sub> dissolution during HIP contributes to an interstitial dissolved N content of about 0.189 mass%, which, together with the higher Si content, increases hardness. Wavelength dispersive spectrometry (WDS) and nanoindentation line scans show decreasing Si and N concentrations from core to shell, resulting in reduced (nano)hardness in the shell. This innovative approach demonstrates the potential to produce AM components with enhanced properties by overcoming the limitations of nitrogen solubility in the steel melt during PBF-LB/M.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100205"},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000148/pdfft?md5=0b96795d1bc1ad1cac1fac3ff935da14&pid=1-s2.0-S2772369024000148-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140271081","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}

引用次数: 0

Additive friction stir deposition of super duplex stainless steel: Microstructure and mechanical properties 超级双相不锈钢的添加剂搅拌摩擦沉积：微观结构和机械性能

Additive manufacturing letters Pub Date : 2024-03-04 DOI: 10.1016/j.addlet.2024.100204

Meet Gor , Matthew Barnett , Daniel Fabijanic , Pinaki Prasad Bhattacharjee

{"title":"Additive friction stir deposition of super duplex stainless steel: Microstructure and mechanical properties","authors":"Meet Gor , Matthew Barnett , Daniel Fabijanic , Pinaki Prasad Bhattacharjee","doi":"10.1016/j.addlet.2024.100204","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100204","url":null,"abstract":"<div><p>Additive Friction Stir Deposition (AFSD) is an emerging solid-state metal additive manufacturing (AM) process that offers several key benefits, including high deposition rates and wrought-equivalent mechanical properties even in the as-deposited condition. The work presented is the first study to report on the development of microstructure and mechanical properties of AFSD-processed duplex stainless steel (DSS2507). The banded microstructure of the starting material was remarkably affected by AFSD processing; the austenite grains exhibited a refined and equiaxed morphology, while the ferrite grains appeared slightly larger and elongated. Microstructural observations revealed that the potential mechanism of microstructure evolution in austenite was discontinuous dynamic recrystallization (DDRX), while in ferrite, it was continuous dynamic recrystallization (CDRX). The occurrence of multiple thermal cycles during the AFSD process resulted in σ phase precipitation, which in turn led to considerable variation in mechanical properties with respect to the build direction. The top region of the as-built part with an insignificant σ phase fraction showed improved tensile strength and ductility combination compared to the as-received DSS2507 as well as other AM-processed DSS2507 alloys.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100204"},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000136/pdfft?md5=2e417667694557ec2266019e852b53b2&pid=1-s2.0-S2772369024000136-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140061897","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}

引用次数: 0

The role of process parameters and printing position on meltpool variations in LPBF Hastelloy X: Insights into laser-plume interaction 工艺参数和印刷位置对 LPBF 哈氏合金 X 熔池变化的影响：激光与熔池相互作用的启示

Additive manufacturing letters Pub Date : 2024-03-01 DOI: 10.1016/j.addlet.2024.100203

Jian Tang , Rafal Wróbel , Pooriya Scheel , Willy Gaechter , Christian Leinenbach , Ehsan Hosseini

{"title":"The role of process parameters and printing position on meltpool variations in LPBF Hastelloy X: Insights into laser-plume interaction","authors":"Jian Tang , Rafal Wróbel , Pooriya Scheel , Willy Gaechter , Christian Leinenbach , Ehsan Hosseini","doi":"10.1016/j.addlet.2024.100203","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100203","url":null,"abstract":"<div><p>Meltpool dimensions play a pivotal role in defining the defects and microstructure state of Laser Powder Bed Fusion (LPBF) builds. Therefore, it is crucial to investigate variations in meltpool geometries under different process conditions. In this work, we fabricated single tracks of LPBF Hastelloy X (HX) alloy under 36 printing conditions and examined the corresponding cross-section meltpool dimensions at two locations across the build platform. This investigation demonstrates the impacts of laser power, scan speed, powder layer thickness, and printing locations on resultant meltpool dimensions. As expected, we observed that meltpool dimensions increase as laser power increases or scan speed decreases. It was also concluded that thicker powder layers lead to wider and shallower meltpools due to reduced laser energy penetration into the solid beneath the powder layer. Additionally, the meltpool dimensions show variations dependent on deposition locations due to the different levels of interaction of the laser and its induced vapor plume, resulting in shallower and wider meltpools. These findings provide a systematic understanding of meltpool dimension variations across various process conditions for LPBF HX alloy, which ultimately offer insights into the formation of defects and microstructure features.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100203"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000124/pdfft?md5=7fd96b76f55bcd16ecbd3194e32dda25&pid=1-s2.0-S2772369024000124-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140051983","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}

引用次数: 0

Investigating the deformation and microstructural evolution of laser powder-bed fusion of Hastelloy X during high temperature fatigue loading 研究高温疲劳加载过程中激光粉末床融合哈氏合金 X 的变形和微观结构演变

Additive manufacturing letters Pub Date : 2024-02-09 DOI: 10.1016/j.addlet.2024.100201

Reza Esmaeilizadeh , Xiaolong Li , Mathias Kuhlow , Stuart Holdsworth , Ali Keshavarzkermani , Hamid Jahed , Ehsan Toyserkani , Ehsan Hosseini

{"title":"Investigating the deformation and microstructural evolution of laser powder-bed fusion of Hastelloy X during high temperature fatigue loading","authors":"Reza Esmaeilizadeh , Xiaolong Li , Mathias Kuhlow , Stuart Holdsworth , Ali Keshavarzkermani , Hamid Jahed , Ehsan Toyserkani , Ehsan Hosseini","doi":"10.1016/j.addlet.2024.100201","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100201","url":null,"abstract":"<div><p>This study investigates the fatigue behaviour of samples made by laser powder-bed fusion of Hastelloy X (LPBF-HX) with as-built and machined surface conditions at 700 °C under fully reversed strain-controlled cyclic loading. Samples with both surface conditions exhibited initially cyclic hardening followed by cyclic softening under large strain amplitude testing, where a slight continuous hardening was observed for tests with smaller strain amplitudes. The samples with machined surfaces showed longer endurance and higher stress ranges than those with as-built surfaces. Post-fatigue-test EBSD analysis showed the formation of the Goss texture and extensive local strain accumulation in the samples tested under high strain amplitude at 700 °C. Fractography investigations revealed that early crack initiation in the samples with as-built surfaces was from stress concentrations induced by valleys on the rough surface. No evidence of crack initiation induced by pre-existing defects was observed in the machined samples, and the excessive slip activity at the surface was found to be responsible for the crack initiation.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100201"},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000100/pdfft?md5=21237ab93c84d6a360f4f9f7f0a3a80e&pid=1-s2.0-S2772369024000100-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139732775","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}

引用次数: 0

Depowdering of an additively manufactured heat exchanger with narrow and turning channels 具有狭窄和转弯通道的添加式制造热交换器的除灰处理

Additive manufacturing letters Pub Date : 2024-02-09 DOI: 10.1016/j.addlet.2024.100202

Wenchao Du, Wenhua Yu, David M. France, Dileep Singh

{"title":"Depowdering of an additively manufactured heat exchanger with narrow and turning channels","authors":"Wenchao Du, Wenhua Yu, David M. France, Dileep Singh","doi":"10.1016/j.addlet.2024.100202","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100202","url":null,"abstract":"<div><p>The evolution of heat exchangers (HXs) manufactured by additive manufacturing techniques is significantly needed. The depowdering solution is a necessity, especially if flow channels are incorporated into the design. In this study, a one-piece HX with multiple layers of internal channels (printed by binder jetting additive manufacturing) was completely depowdered through a developed approach. Each HX channel has a semi-elliptical geometry, four perpendicular turnings along the approximately 200-mm length, and an approximately 80-mm center segment that is inaccessible due to the turnings. To depowder this component, two approaches including the compressed air and the vortex motion were tested first. It was found that the compressed air or vortex motion alone could partially depowder the internal unbound powder of the printed heat exchanger. Consequently, for complete depowdering, a combined approach of the vortex motion and compressed air blowing with multiple cycles was developed and tested. A study of the effect of the vortex duration in each depowdering cycle was conducted, and results showed that an increase from five minutes to ten minutes resulted in a reduced number of stages for a complete depowdering.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100202"},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000112/pdfft?md5=f9df06c7eeaefb2858b45396a0e2df02&pid=1-s2.0-S2772369024000112-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139732776","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}

引用次数: 0

Understanding the role of geometry and interlayer cooling time on microstructure variations in LPBF Ti6Al4V through part-scale scan-resolved thermal modeling 通过部分尺度扫描分辨热建模了解几何形状和层间冷却时间对 LPBF Ti6Al4V 微观结构变化的作用

Additive manufacturing letters Pub Date : 2024-02-03 DOI: 10.1016/j.addlet.2024.100197

Alaa Olleak , Evan Adcock , Shawn Hinnebusch , Florian Dugast , Anthony D. Rollett , Albert C. To

{"title":"Understanding the role of geometry and interlayer cooling time on microstructure variations in LPBF Ti6Al4V through part-scale scan-resolved thermal modeling","authors":"Alaa Olleak , Evan Adcock , Shawn Hinnebusch , Florian Dugast , Anthony D. Rollett , Albert C. To","doi":"10.1016/j.addlet.2024.100197","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100197","url":null,"abstract":"<div><p>In this study, we investigated the microstructural variation of Ti-6Al-4 V in inverted pyramid parts built using Laser Powder Bed Fusion (LPBF). Two parts were fabricated with and without ghost parts to study the effects of interlayer delay time on thermal history and microstructure. Finite Element Method (FEM) based process simulation was used to predict the thermal history and cooling rates during the LPBF process to understand the location-specific microstructure and mechanical properties variation. The thermal analysis findings revealed that the variations in the cooling rates and pre-deposition temperature were notably significant. Within the same part, the cooling rates exhibited significant variations, differing by up to three orders of magnitude in two scenarios: (1) within the same layer, influenced by the proximity to the edges, and (2) at different heights, attributable to the strongly varying cross-section. Comparing the two parts, the cooling rates of the part with ghost parts were approximately two orders of magnitude higher than in the part without the ghost parts. This significant difference can be attributed to the extended interlayer cooling time and lower pre-deposition temperature resulting from the presence of two ghost parts which introduced an effective delay time between laser scans. Experimental validation against microstructure images and hardness measurements showed similar trends with the predicted results. These findings provide valuable insights into controlling microstructure at specific locations during LPBF fabrication, which is essential for building complex geometries with controlled material properties.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100197"},"PeriodicalIF":0.0,"publicationDate":"2024-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000069/pdfft?md5=23a8fa57535c558f207af2fab8ffb6e5&pid=1-s2.0-S2772369024000069-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139714817","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}

引用次数: 0

Geometry repeatability and prediction for personalized medical devices made using multi-jet fusion additive manufacturing 使用多射流融合增材制造技术制造个性化医疗器械的几何重复性和预测性

Additive manufacturing letters Pub Date : 2024-02-01 DOI: 10.1016/j.addlet.2024.100200

Christopher H. Conway , Davis J. McGregor , Tristan Antonsen , Charles Wood , Chenhui Shao , William P. King

{"title":"Geometry repeatability and prediction for personalized medical devices made using multi-jet fusion additive manufacturing","authors":"Christopher H. Conway , Davis J. McGregor , Tristan Antonsen , Charles Wood , Chenhui Shao , William P. King","doi":"10.1016/j.addlet.2024.100200","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100200","url":null,"abstract":"<div><p>As additive manufacturing (AM) production volumes grow to the industrial scale, quality systems must also scale to verify that every part satisfies requirements. Quality systems are particularly challenging for personalized medical devices, where every patient requires a unique design. This research studies the repeatability of an additively manufactured guide for knee surgery that is personalized to the size and shape of a patient and explores concepts for predicting geometric accuracy. We created 258 unique surgical guide designs with different sizes of the critical features to simulate practical conditions, and manufactured 2100 parts using multi-jet fusion AM. An automated measurement technique collected 8400 individual feature dimensions. Across four critical features, the standard deviation of feature size was 0.076 to 0.173 mm, however the accuracy was consistently different than the target dimensions by -0.308 to 0.017 mm. We show how machine learning (ML) models can predict these geometry distortions and explore the number of parts required to effectively train these models. The accuracy of these models are 0.033 to 0.075 mm, such that the part shape distortion can be accurately predicted to within one standard deviation across a wide range of part sizes.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100200"},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000094/pdfft?md5=b39301c043f9bb05fbbeac341c3a063d&pid=1-s2.0-S2772369024000094-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139675732","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}

引用次数: 0

Importance of feedstock powder selection for mechanical properties improvement of cold spray additively manufactured Ti6Al4V deposits 原料粉末选择对改善冷喷加成法制造的 Ti6Al4V 沉积物机械性能的重要性

Additive manufacturing letters Pub Date : 2024-01-30 DOI: 10.1016/j.addlet.2024.100199

Jan Kondas , Mario Guagliano , Sara Bagherifard , Reeti Singh , Jan Cizek , Frantisek Lukac , Pavel Konopik , Sylwia Rzepa

{"title":"Importance of feedstock powder selection for mechanical properties improvement of cold spray additively manufactured Ti6Al4V deposits","authors":"Jan Kondas , Mario Guagliano , Sara Bagherifard , Reeti Singh , Jan Cizek , Frantisek Lukac , Pavel Konopik , Sylwia Rzepa","doi":"10.1016/j.addlet.2024.100199","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100199","url":null,"abstract":"<div><p>CSAM (cold spray additive manufacturing) of Ti6Al4V is a challenging task and high-quality deposits conforming to the AM application standards have not been developed so far. In our study, two distinct feedstock Ti6Al4V powders with different morphology and microstructure, spherical and crystalline, were used and their influence on the deposits was investigated in terms of microstructure as well as tensile properties. The results indicate the mechanical strength and ductility of the as-deposited samples to be in the range of 8–30 % compared to wrought Ti6Al4V and highlight a significant anisotropy in different in-plane directions. The post-treatments of the deposits from the spherical, plasma atomized powder effectively reduced the porosity and triggered microstructural homogenization and recrystallization, leading to a significant increase in the yield and tensile strengths, reaching 892 MPa and 954 MPa, respectively, while achieving an enormous enhancement in the elongation to 21.6 % at the same time. This was in a striking contrast to the deposits from the crystalline powder: despite the yield and tensile strength increase to 853 MPa and 1058 MPa, respectively, the elongation remained virtually zero, highlighting the importance of the feedstock powder selection in cold spray additive manufacturing of Ti6Al4V.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100199"},"PeriodicalIF":0.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000082/pdfft?md5=020263670df00806d7a5dc302b676183&pid=1-s2.0-S2772369024000082-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139714815","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}

引用次数: 0

Measurement of focal plane error in laser powder bed fusion machines 激光粉末床熔融机焦平面误差的测量

Additive manufacturing letters Pub Date : 2024-01-28 DOI: 10.1016/j.addlet.2024.100196

Jaime Berez , Enea Dushaj , Elliott Jost , Christopher Saldaña , Katherine Fu

{"title":"Measurement of focal plane error in laser powder bed fusion machines","authors":"Jaime Berez , Enea Dushaj , Elliott Jost , Christopher Saldaña , Katherine Fu","doi":"10.1016/j.addlet.2024.100196","DOIUrl":"10.1016/j.addlet.2024.100196","url":null,"abstract":"<div><p>Amongst the many sub-systems that make up laser powder bed fusion (PBF-LB) machines, the optomechanical sub-system stands out due to its potential for off-nominal performance but incommensurate level of study on performance evaluation. Nominally, the optomechanical system focuses the laser onto a planar field which is at a controlled position and orientation relative to the powder bed. Deviations from this assumed condition, sometimes referred to as defocus or focus offset, have the potential to significantly impact the manufacturing process by influencing the energy intensity at the process zone. Herein, a novel, high-throughput, low-cost, artifact-based methodology to measure focus offset is detailed. In a single continuous build process, tracks at varying offsets from the build plane were created by ablating the coating on discrete coupons located throughout the build area. By examining these track widths, the focus offset was determined at a relatively fine spatial resolution over the build space, down to 25 mm intervals along the <em>x</em> and <em>y</em> directions, thus ascertaining the discrepancy between the laser focal plane and the build plane, i.e., focal plane error. Results were found to agree with reference measurements to within 0.27 mm over the entire build space and defocus levels ranging from approximately -1.6 to 1.7 mm were discovered. Field sag and optomechanical misalignment were the major casual factors. It is concluded that similar or more severe levels of defocus may be present in the typical PBF-LB machine, which may impart considerable impacts to the overall PBF-LB process.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"9 ","pages":"Article 100196"},"PeriodicalIF":0.0,"publicationDate":"2024-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000057/pdfft?md5=48a3f31fc042735e2d8a34b4e8a71267&pid=1-s2.0-S2772369024000057-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139638768","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}

引用次数: 0