Additive manufacturing letters最新文献_第2页

Jet on demand—A pneumatically driven molten metal jetting method for printing crack-free aluminum components 按需喷射--用于打印无裂纹铝制部件的气动驱动熔融金属喷射方法

IF 4.2

Additive manufacturing letters Pub Date : 2024-09-17 DOI: 10.1016/j.addlet.2024.100240

{"title":"Jet on demand—A pneumatically driven molten metal jetting method for printing crack-free aluminum components","authors":"","doi":"10.1016/j.addlet.2024.100240","DOIUrl":"10.1016/j.addlet.2024.100240","url":null,"abstract":"<div><div>Additive manufacturing (AM) of many traditional aluminum alloys is difficult due to hot cracking during cooling, which motivates investigating alternative AM methods that can mitigate this challenge. Here we demonstrate a new pneumatically driven molten metal jetting (MMJ) AM technique which uses a longer pressure pulse width to produce a jet of liquid metal that reaches the heated build plate. The “jet on demand” technique is utilized to build Al-6061 parts on heated build plates. Due to the large thermal mass contained in each jet, excellent adhesion is observed between droplets and layers while still maintaining dimensional control to produce parts with high relative densities (>98%). While as-printed parts exhibit different microstructure and hardness than traditional Al-6061, both microstructure and hardness are restored to traditionally processed values through a traditional T6 heat treatment. Microhardness values of 104 HV were obtained for printed Al-6061, which compares well to wrought properties. We observe that high build plate temperatures allow for lower solidification rates and eliminate hot cracking. These results point to a method for additively manufacturing traditional aluminum or other alloys that cannot currently be additively manufactured due to hot cracking.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000483/pdfft?md5=2d587638c9808e9d5184e4e2c4bcff5b&pid=1-s2.0-S2772369024000483-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310901","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

Deep learning based automated quantification of powders used in additive manufacturing 基于深度学习的增材制造所用粉末自动定量分析

IF 4.2

Additive manufacturing letters Pub Date : 2024-09-14 DOI: 10.1016/j.addlet.2024.100241

引用次数: 0

In-situ characterization of defect formation and elimination dynamics during electron beam melting using high-speed X-ray imaging 利用高速 X 射线成像对电子束熔化过程中的缺陷形成和消除动态进行现场表征

IF 4.2

Additive manufacturing letters Pub Date : 2024-09-05 DOI: 10.1016/j.addlet.2024.100239

{"title":"In-situ characterization of defect formation and elimination dynamics during electron beam melting using high-speed X-ray imaging","authors":"","doi":"10.1016/j.addlet.2024.100239","DOIUrl":"10.1016/j.addlet.2024.100239","url":null,"abstract":"<div><p>Electron beam melting (EBM), also known as electron beam powder bed fusion (EB-PBF), is a metal additive manufacturing (AM) technology that can make metal parts that are difficult, inefficient, or unachievable through conventional manufacturing routes and other AM technologies. However, a comprehensive understanding of the dynamics of electron beam-matter interactions in EBM remains elusive, which is a barrier for the development and adoption of EBM technology. Here, we report the dynamics and mechanisms of pore formation, pore elimination, and crack elimination in EBM. Three mechanisms of pore formation are observed: (1) pore formation from feedstock powders, (2) pore formation from pre-existing defects, and (3) pore captured by solidification front. One pore elimination mechanism is discovered: pore elimination due to metal vapor condensation, which is unique to EBM. One crack elimination mechanism is uncovered: crack elimination through remelting. These results will enhance the understanding of defect formation and evolution mechanisms in EBM and may inspire the invention of effective approaches to mitigate and control defects (porosity and cracks) in EBM.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000471/pdfft?md5=4c8677c4726e2063dec2b6d8c31a7ae2&pid=1-s2.0-S2772369024000471-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142272233","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

Laser additive manufacturing of a carbon-supersaturated β-Ti alloy for biomaterial application 用于生物材料应用的碳过饱和 β-Ti 合金激光快速成型技术

IF 4.2

Additive manufacturing letters Pub Date : 2024-09-04 DOI: 10.1016/j.addlet.2024.100233

{"title":"Laser additive manufacturing of a carbon-supersaturated β-Ti alloy for biomaterial application","authors":"","doi":"10.1016/j.addlet.2024.100233","DOIUrl":"10.1016/j.addlet.2024.100233","url":null,"abstract":"<div><p>Developing high-performance β-Ti alloys is a persistent and long-term demand for the advancement of next-generation biomaterials. In this study, a strategy of leveraging the unique characteristics of laser powder bed fusion (L-PBF) technique and nanocarbon materials was proposed to design a novel carbon-supersaturated β-Ti alloy. Ultrathin graphene oxide (GO) sheets were closely covering onto spherical Ti-15Mo-5Zr-3Al (Ti1553) powders, enhancing laser absorptivity while maintaining good flowability. Consequently, the GO-added Ti1553 builds tended to be denser than the initial ones, indicating an improved additive manufacturability. During <span>L</span>-PBF, GO sheets were completely dissolved into the Ti1553 matrix, generating fully carbon-supersaturated β-Ti structures with a reduced grain size. Thanks to the exceptional strengthening effects of high-concentration solid-solution carbon (∼0.05 wt%), the GO/Ti1553 builds achieved a high ultimate tensile strength of 1166 MPa. Moreover, as revealed by the immunofluorescence staining experiments, the GO/Ti1553 builds demonstrated a retained cytocompatibility. This study provides new insight into composition and processing design of high-performance Ti components for biomedical applications.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000410/pdfft?md5=f91ca5affc8917d8cbab1f3b90e6769a&pid=1-s2.0-S2772369024000410-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142137012","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

On the role of the preheat temperature in electron-beam powder bed fusion processed IN718 论预热温度在电子束粉末床熔融处理 IN718 中的作用

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-31 DOI: 10.1016/j.addlet.2024.100238

{"title":"On the role of the preheat temperature in electron-beam powder bed fusion processed IN718","authors":"","doi":"10.1016/j.addlet.2024.100238","DOIUrl":"10.1016/j.addlet.2024.100238","url":null,"abstract":"<div><p>Process parameters optimization in additive manufacturing (AM) is usually required to unlock superior properties, and this is often facilitated by modeling. In electron beam powder bed fusion (E-PBF), the preheat temperature is an important parameter to be optimized as it significantly influences the microstructure and properties. Here we compare the effect of two preheat temperatures (1000 and 950°C, above and below δ-phase solvus temperature) on the microstructural evolution of E-PBF IN718 Ni-based superalloy. Using thermal and thermo-kinetic modeling, we predict microstructural changes and compare them with experimental findings. A decrease of only 50°C in the preheat temperature has a low impact on the solidification microstructure with a slight reduction in columnar grain width. In the solid-state, higher preheating causes intergranular δ-phase precipitation, contributing to a higher γ\" precipitation potential, formation of co-precipitates, and higher hardness. The lower preheat temperature induces intergranular and intragranular δ-phase precipitation, reducing the γ\" precipitation potential and hardness. The chemical composition of γ' and γ\" is largely unaffected by the preheat temperature variation. These insights underscore the importance of preheat temperature optimization in microstructure design and property control during E-PBF.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S277236902400046X/pdfft?md5=477e53db60389c1888ac301d3dfb2fff&pid=1-s2.0-S277236902400046X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142129481","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 manufacturing of novel aluminium matrix composites with enhanced strength and processability via boron nitride functionalization 通过氮化硼功能化快速制造具有更高强度和加工性能的新型铝基复合材料

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-30 DOI: 10.1016/j.addlet.2024.100237

{"title":"Additive manufacturing of novel aluminium matrix composites with enhanced strength and processability via boron nitride functionalization","authors":"","doi":"10.1016/j.addlet.2024.100237","DOIUrl":"10.1016/j.addlet.2024.100237","url":null,"abstract":"<div><p>The present work systematically investigates the effects of BN nanopowder functionalization on the processability, microstructure and tensile response of the custom Powder Bed Fusion Laser Beam (PBF-LB) Al alloy ‘AMALLOY3D’. The results show that a minor addition of BN (0.3 % by weight) not only produces near fully dense parts (99.91 %), but is also paired with improved flowability, enhancing the overall processability. Electron backscatter diffraction (EBSD) analysis revealed the transformation to a fully equiaxed grain structure in the BN-functionalized material, resulting in a 40 % increase in yield strength. Energy dispersive spectroscopy using a scanning transmission electron microscope (STEM-EDS) was employed to reveal the intricate secondary phases’ arrangements. These observations coupled with the help of the CALPHAD approach led to the reconstruction of the solidification history of AMALLOY3D and the BN-functionalized material. The present study unravels the complex dynamics leading to the columnar-to-equiaxed transition in BN-reinforced AMCs, proving that such unique microstructures and exceptional tensile properties can be achieved without compromising PBF-LB processability.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000458/pdfft?md5=5417a120a2449cbec0b7c665db6ad06b&pid=1-s2.0-S2772369024000458-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142129482","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

Anomalous temperature-dependent strength of copper alloy manufactured by laser-beam powder bed fusion 用激光束粉末床熔合技术制造的铜合金强度随温度变化的异常现象

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-24 DOI: 10.1016/j.addlet.2024.100236

引用次数: 0

AMGPT: A large language model for contextual querying in additive manufacturing AMGPT：用于增材制造语境查询的大型语言模型

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-22 DOI: 10.1016/j.addlet.2024.100232

{"title":"AMGPT: A large language model for contextual querying in additive manufacturing","authors":"","doi":"10.1016/j.addlet.2024.100232","DOIUrl":"10.1016/j.addlet.2024.100232","url":null,"abstract":"<div><p>Generalized large language models (LLMs) such as GPT-4 may not provide specific answers to queries formulated by materials science researchers. These models may produce a high-level outline but lack the capacity to return detailed instructions on manufacturing and material properties of novel alloys. We introduce “AMGPT”, a specialized LLM text generator designed for metal AM queries. The goal of AMGPT is to assist researchers and users in navigating a curated corpus of literature. Instead of training from scratch, we employ a pre-trained Llama2-7B model from Hugging Face in a Retrieval-Augmented Generation (RAG) setup, utilizing it to dynamically incorporate information from <span><math><mo>∼</mo></math></span>50 AM papers and textbooks in PDF format. Mathpix is used to convert these PDF documents into TeX format, facilitating their integration into the RAG pipeline managed by LlamaIndex. A query retrieval function has also been added, enabling the system to fetch relevant literature from Elsevier journals based on the context of the query. Expert evaluations of this project highlight that specific embeddings from the RAG setup accelerate response times and maintain coherence in the generated text.</p></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772369024000409/pdfft?md5=8d7e38c2365561cad4541597909ff24b&pid=1-s2.0-S2772369024000409-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142086895","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

Spatial frequency modulation imaging for laser processing applications 用于激光加工应用的空间频率调制成像技术

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-22 DOI: 10.1016/j.addlet.2024.100231

引用次数: 0

High-temperature tensile behaviors of an ultra-strong aluminum alloy fabricated by additive manufacturing 增材制造超强铝合金的高温拉伸行为

IF 4.2

Additive manufacturing letters Pub Date : 2024-08-17 DOI: 10.1016/j.addlet.2024.100234

引用次数: 0