Additive manufacturing letters最新文献_第4页

Interpenetrating microstructure in laser powder-bed fusion parts using selective rescanning 利用选择性重扫描技术研究激光粉末床熔融部件中的穿透微观结构

IF 4.2

Additive manufacturing letters Pub Date : 2024-07-01 DOI: 10.1016/j.addlet.2024.100221

Bharath Bhushan Ravichander , Shweta Hanmant Jagdale , Golden Kumar

{"title":"Interpenetrating microstructure in laser powder-bed fusion parts using selective rescanning","authors":"Bharath Bhushan Ravichander , Shweta Hanmant Jagdale , Golden Kumar","doi":"10.1016/j.addlet.2024.100221","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100221","url":null,"abstract":"<div><p><em>In-situ</em> microstructural control is desirable in additively manufactured metal parts due to limited post-processing options for net-shaped components. Here, we introduce a novel selective rescanning approach to control the local solidification conditions and the microstructure in metal parts produced by laser powder-bed fusion (LPBF). We show that the melt pool dimensions, grain size, and sub-grain cell structure can be selectively varied in three dimensions to engineer the mechanical response of LPBF parts. The lattice-based rescanning strategy enables the formation of an interpenetrating microstructure comprised of fine and coarse grains. The localized heating and cooling-induced thermal stresses increase the hardness and tensile strength of rescanned specimens. The study shows the potential of selective rescanning strategy as a promising avenue for achieving precise control of microstructure and properties in as-printed LPBF parts without subsequent processing.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100221"},"PeriodicalIF":4.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000306/pdfft?md5=a3c097750235487cc665b24857531d36&pid=1-s2.0-S2772369024000306-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141480277","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

GRCop-42: Comparison between laser powder bed fusion and laser powder direct energy deposition GRCop-42：激光粉末床熔融与激光粉末直接能量沉积的比较

IF 4.2

Additive manufacturing letters Pub Date : 2024-07-01 DOI: 10.1016/j.addlet.2024.100224

Gabriel Demeneghi , Paul Gradl , Jason R. Mayeur , Kavan Hazeli

引用次数: 0

Printing vertical flat surfaces in thermoset big area additive manufacturing 在热固性大面积增材制造中打印垂直平面

IF 4.2

Additive manufacturing letters Pub Date : 2024-07-01 DOI: 10.1016/j.addlet.2024.100226

Marco Brander, Berin Šeta, David Bue Pedersen, Jon Spangenberg

{"title":"Printing vertical flat surfaces in thermoset big area additive manufacturing","authors":"Marco Brander, Berin Šeta, David Bue Pedersen, Jon Spangenberg","doi":"10.1016/j.addlet.2024.100226","DOIUrl":"10.1016/j.addlet.2024.100226","url":null,"abstract":"<div><p>In extrusion-based additive manufacturing, achieving high surface quality typically involves using small layer heights to reduce the size of grooves between layers. However, this approach can be both less effective and time-consuming in big-area additive manufacturing. Therefore, the current focus is on investigating methods for printing with fewer layers without compromising surface quality. In this study, single-strand walls were printed using a two-component thermoset material, where different nozzle designs and printing strategies are explored to achieve the flattest possible surface. The success of each approach was evaluated by measuring the percentage of material that required removal to achieve a perfect vertical flat wall. The results suggested that incorporating vertical wings to contain the material in the desired shape was beneficial. Furthermore, the study introduced the idea of adjustable layer heights to mitigate layer deformation. This deformation is most noticeable in the initial layers but largely affects all subsequent printed layers. Finally, making the wings have an angle with regard to the printing direction or trapezoidal wings, served as a pressure funnel that produced the greatest improvement in surface quality. These changes allowed for a reduction of the amount of material which would need to be removed to achieve a flat wall without grooves from 14.3% for a standard print from a round nozzle, to 2.5% for an optimized strand. The research shows a promising path to producing entirely flat vertical structures, even when printing with still-deformable, thermoset materials in the context of big-area additive manufacturing.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100226"},"PeriodicalIF":4.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000343/pdfft?md5=f3dc57a6059c196a163df977d90f95a8&pid=1-s2.0-S2772369024000343-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141850721","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

Microstructure and mechanical response of as-built and solution-annealed LPBF Hastelloy X under high-temperature fatigue loading 坯料和固溶退火 LPBF 哈氏合金 X 在高温疲劳载荷下的微观结构和机械响应

IF 4.2

Additive manufacturing letters Pub Date : 2024-07-01 DOI: 10.1016/j.addlet.2024.100227

X. Li , R. Esmaeilizadeh , E. Hosseini

{"title":"Microstructure and mechanical response of as-built and solution-annealed LPBF Hastelloy X under high-temperature fatigue loading","authors":"X. Li , R. Esmaeilizadeh , E. Hosseini","doi":"10.1016/j.addlet.2024.100227","DOIUrl":"10.1016/j.addlet.2024.100227","url":null,"abstract":"<div><p>This study investigates the microstructural characteristics and the high-temperature mechanical behavior of Hastelloy X, fabricated via laser powder-bed fusion (LPBF) technology. Hastelloy X, a solid solution-strengthened nickel-based superalloy known for its high strength and oxidation resistance at elevated temperatures, has gained significant interest for the fabrication of complex aerospace components through LPBF technology. The study initially focuses on the impact of solution annealing heat treatment at 1227 °C on the alloy microstructure, based on scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations. It then explores the fatigue and cyclic deformation response of the alloy at 750 °C across different strain ranges, comparing the as-built and solution-annealed conditions. To understand the observed differences in the cyclic mechanical response of as-built and solution-annealed LPBF HX, for a particular condition, a set of dedicated tests have been performed and interrupted at selected numbers of cycles in the different stages of the mechanical response. At each interruption point, specimens have been examined by TEM to provide an in-depth understanding of the effect of dislocation microstructural evolution on the high-temperature cyclic mechanical response of the alloy.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100227"},"PeriodicalIF":4.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000355/pdfft?md5=3e6d8516fe09fdcae1e1cd847567a059&pid=1-s2.0-S2772369024000355-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141846392","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

Oxidation behavior of Cu–Ag alloy in-situ manufactured via laser powder bed fusion 通过激光粉末床熔化原位制造的铜银合金的氧化行为

IF 4.2

Additive manufacturing letters Pub Date : 2024-07-01 DOI: 10.1016/j.addlet.2024.100228

Nadia Azizi , Hamed Asgari , Ehsan Toyserkani

引用次数: 0

Extracting powder bed features via electron optical images during electron beam powder bed fusion 通过电子束粉末床融合过程中的电子光学图像提取粉末床特征

Additive manufacturing letters Pub Date : 2024-05-07 DOI: 10.1016/j.addlet.2024.100220

Matthias Markl, Mohammad Reza Azadi Tinat, Timo Berger, Jakob Renner, Carolin Körner

{"title":"Extracting powder bed features via electron optical images during electron beam powder bed fusion","authors":"Matthias Markl, Mohammad Reza Azadi Tinat, Timo Berger, Jakob Renner, Carolin Körner","doi":"10.1016/j.addlet.2024.100220","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100220","url":null,"abstract":"<div><p>Electron beam powder bed fusion offers the unique opportunity to observe the process by measuring scattered electrons on a metal detector. This technique is the state of the art in generating electron optical images of the build area after melting using single- or multi-detector setups. The images enable the detection of surface defects like porosity or material transport by reconstructing the surface topography. Internal defects such as layer-bonding defects cannot be identified. Many of these defects, particularly layer-bonding defects, often originate from an irregular distribution of the powder bed.</p><p>This work introduces an additional process step by recording an electron optical image after the distribution of the powder bed. Combining this with an electron optical image after melting the previous layer enables extraction of powder bed features such as the current powder bed height. The underlying method bases on the correlation of experimental measurements and numerical simulations of the intensity of the electron optical signal for different powder bed heights. With this approach, it is possible to identify irregular powder distributions, such as uncovered areas of previously molten material or locally varying powder bed heights. This information is crucial for online monitoring and real time process control. Exemplary, this opens the opportunity of healing the powder bed by an additional raking step.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100220"},"PeriodicalIF":0.0,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S277236902400029X/pdfft?md5=bcfec8a21ec24fa6bea53ac48b89eac6&pid=1-s2.0-S277236902400029X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140918694","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

Active-mixing printhead for on-the-fly composition adjustment of multi component materials in Direct Ink Writing 用于在直接墨水书写中即时调整多组分材料成分的主动式混合喷头

Additive manufacturing letters Pub Date : 2024-05-03 DOI: 10.1016/j.addlet.2024.100217

Simon Teves , Tobias Biermann , Arved Ziebehl , Jan Gerrit Eckert , Ole Hill , Panpan Xia , Merve Wollweber , Tammo Ripken , Nadja C. Bigall , Roland Lachmayer

{"title":"Active-mixing printhead for on-the-fly composition adjustment of multi component materials in Direct Ink Writing","authors":"Simon Teves , Tobias Biermann , Arved Ziebehl , Jan Gerrit Eckert , Ole Hill , Panpan Xia , Merve Wollweber , Tammo Ripken , Nadja C. Bigall , Roland Lachmayer","doi":"10.1016/j.addlet.2024.100217","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100217","url":null,"abstract":"<div><p>Multi-Material Additive Manufacturing (MMAM) enables the grading of material properties and the integration of functions within printed parts. While most MMAM methods are limited to process single-component or pre-mixed multi-component materials, the in-process mixing and extrusion of multi-component materials enables innovative material properties and use cases. When processing liquid multi-component materials, the individual component streams need to be homogenized in-process, but the required volume in conventional passive mixing hinders rapid transitions in material composition. In this paper, a two component printhead is presented which combines an active mixing approach with a continuous composition adjustment for a third additive. The approach to control the mixing composition is to influence the hydrodynamic equilibrium of individual material streams before merging them near the point of extrusion. The printhead’s functionality is verified in terms of mixing homogeneity and transition speed between material compositions.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100217"},"PeriodicalIF":0.0,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000264/pdfft?md5=8321dcf3b16587f2187170572a05c295&pid=1-s2.0-S2772369024000264-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140880443","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

Effect of process atmosphere on microstructure, melt pool, texture, precipitate characteristics, and mechanical properties of laser powder bed fusion Fe-12Cr-6Al 工艺气氛对激光粉末床熔融 Fe-12Cr-6Al 的微观结构、熔池、纹理、析出物特征和力学性能的影响

Additive manufacturing letters Pub Date : 2024-05-01 DOI: 10.1016/j.addlet.2024.100219

Omer Cakmak , Seong Gyu Chung , Seung-Hoon Lee , JiHoe Koo , Hwasung Yeom , Jung-Wook Cho

{"title":"Effect of process atmosphere on microstructure, melt pool, texture, precipitate characteristics, and mechanical properties of laser powder bed fusion Fe-12Cr-6Al","authors":"Omer Cakmak , Seong Gyu Chung , Seung-Hoon Lee , JiHoe Koo , Hwasung Yeom , Jung-Wook Cho","doi":"10.1016/j.addlet.2024.100219","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100219","url":null,"abstract":"<div><p>This study investigates the impact of atmospheres (Ar and N<sub>2</sub>) on Fe-12Cr-6Al alloy fabricated using laser powder bed fusion (L-PBF) in terms of melt pool shape/size, microstructure, precipitate characteristics, and mechanical properties. The sample built in the N<sub>2</sub> atmosphere exhibited lower porosity, wider melt pools, and no Al<sub>2</sub>O<sub>3</sub> agglomeration. Oxygen content decreased from 0.012 to 0.0045 (wt.%), and nitrogen content increased from 0.013 to 0.02 (wt.%). The Ar-printed sample had a yield strength (YS) of 232 ± 15 MPa, ultimate tensile strength (UTS) of 286 ± 10 MPa, and total elongation (TE) of 6.4 ± 1.3 %, while the N<sub>2</sub>-printed sample showed significant improvements of the mechanical properties: YS of 315 ± 11 MPa, UTS of 401 ± 11 MPa, and TE of 7.8 ± 1.1 %. Therefore, N<sub>2</sub> might be considered to replace Ar as a cost-effective shielding gas for FeCrAl alloys, with improved properties.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100219"},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000288/pdfft?md5=ba051126cb68daecf2d4b3acf0654ffb&pid=1-s2.0-S2772369024000288-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140822994","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

Mitigation of gravity-induced distortions of binder-jetting components during rotational sintering 缓解旋转烧结过程中粘合剂喷射部件因重力引起的变形

Additive manufacturing letters Pub Date : 2024-04-26 DOI: 10.1016/j.addlet.2024.100215

Thomas Grippi , Elisa Torresani , Alberto Cabo Rios , Andrii L. Maximenko , Marco Zago , Ilaria Cristofolini , Alberto Molinari , Rajendra K. Bordia , Eugene A. Olevsky

{"title":"Mitigation of gravity-induced distortions of binder-jetting components during rotational sintering","authors":"Thomas Grippi , Elisa Torresani , Alberto Cabo Rios , Andrii L. Maximenko , Marco Zago , Ilaria Cristofolini , Alberto Molinari , Rajendra K. Bordia , Eugene A. Olevsky","doi":"10.1016/j.addlet.2024.100215","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100215","url":null,"abstract":"<div><p>Using theory and simulations, the challenge of gravity-induced distortions during sintering is addressed and a mitigation strategy is proposed. Based on the continuum theory of sintering, the finite element simulation demonstrates the advantages of a rotating furnace to counteract gravity forces during sintering. Its application for stainless steel hollow parts produced by additive manufacturing (binder jetting) is demonstrated, numerically, for reliable industrial production of complex shapes. Sintering a tube in a very slow rotating motion exhibits an improvement in the final deformation ratio compared to a conventional sintering process.</p><p>The same concept has been adapted for higher furnace revolution speeds and the centrifugal force is now surpassing the effects of gravity. An extended study of sintering under microgravity for space-borne applications is also widely depicted with the same model. Indeed, it shows the possibility of reproducing Earth's sintering conditions at places where gravity is insufficient to provide acceptable densification and shape conservation during sintering.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100215"},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000240/pdfft?md5=d925aaba3ed20a08896410422e09d919&pid=1-s2.0-S2772369024000240-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140817081","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

A novel feature engineering approach for predicting melt pool depth during LPBF by machine learning models 利用机器学习模型预测 LPBF 期间熔池深度的新型特征工程方法

Additive manufacturing letters Pub Date : 2024-04-26 DOI: 10.1016/j.addlet.2024.100214

Mohammad Hossein Mosallanejad , Hassan Gashmard , Mahdi Javanbakht , Behzad Niroumand , Abdollah Saboori

{"title":"A novel feature engineering approach for predicting melt pool depth during LPBF by machine learning models","authors":"Mohammad Hossein Mosallanejad , Hassan Gashmard , Mahdi Javanbakht , Behzad Niroumand , Abdollah Saboori","doi":"10.1016/j.addlet.2024.100214","DOIUrl":"https://doi.org/10.1016/j.addlet.2024.100214","url":null,"abstract":"<div><p>Melt pool geometry is a deterministic factor affecting the characteristics of metal Additive Manufacturing (AM) components. The wide array of physical and thermal phenomena involved during the formation of the AM melt pool, along with the great variety of alloy compositions and AM methods, coupled with the clear influence of multiple process parameters, make it difficult to predict the melt pool geometry under a given set of conditions. Therefore, using Artificial Intelligence (AI) approaches such as Machine Learning (ML) is necessary for accurate predictions. Using a physics-informed feature selection strategy along with the application of atomic features for the first time, this work aims to offer accurately trained models relying on existing high-fidelity data for most common alloys in AM academia and industry, i.e., 316 L stainless steel, Ti6Al4V, and AlSi10Mg. Multiple ML algorithms were trained, and the results revealed that the average R<sup>2</sup> and RMSE obtained by the K-fold cross-validation (<em>K</em> = 5) were significantly enhanced when laser and material properties, inspired by the analytical models for AM melt pool geometry, were used as the model features. Removing the excess features and applying atomic features further enhanced the accuracy of the models. As a result, R<sup>2</sup> for the XGBoost, CatBoost, and GPR models were 0.907, 0.889, and 0.882, respectively, while the hold-out cross-validation led to 0.978, 0.976, and 0.945, respectively. Furthermore, the results showed that the XGBoost model outperforms the Rosenthal equation. This approach provides a pathway to more accurately predict the properties of metal AM components.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"10 ","pages":"Article 100214"},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000239/pdfft?md5=bd29e5e0479e946efb53b873e042ea15&pid=1-s2.0-S2772369024000239-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140817062","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