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Stacked-origami mechanical metamaterial with tailored multistage stiffness 具有定制多级刚度的堆叠折纸机械超材料
IF 8.4 Pub Date : 2021-08-27 DOI: 10.21203/rs.3.rs-849340/v1
G. Wen, Gaoxi Chen, K. Long, Xuan Wang, Jie Liu, Y. Xie
Origami-baed metamaterial has shown remarkable mechanical properties rarely found in natural materials, but achieving tailored multistage stiffness is still a challenge. This study proposes a novel zigzag-base stacked-origami (ZBSO) metamaterial with tailored multistage stiffness property based on crease customization and stacking strategies. A high precision finite element (FE) model to identify the stiffness characteristics of the ZBSO metamaterial has been established, and its accuracy is validated by quasi-static compression experiments. Using the verified FE model, we demonstrate that the multistage stiffness of the ZBSO metamaterial can be effectively tailored through two manners, i.e. varying the microstructures (through introducing new creases to the classical Miura origami unit cell) and altering the stacking way. Three strategies are utilized to vary the microstructure, i.e. adding new creases to the right, left, or both sides of the unit cell. We further reveal that the proposed ZBSO metamaterial has several outstanding advantages compared with traditional mechanical metamaterials, e.g. material independent, scale-invariant, lightweight, and excellent energy absorption capacity. The unravelled superior mechanical properties of the ZBSO metamaterials pave the way for the design of the next-generation cellular metamaterials with tailored stiffness properties.
基于折纸的超材料表现出了在天然材料中很少发现的卓越机械性能,但实现定制的多级刚度仍然是一个挑战。本文提出了一种基于折痕定制和堆叠策略的具有定制多级刚度特性的新型之字形基叠层折纸(ZBSO)超材料。建立了用于识别ZBSO超材料刚度特性的高精度有限元模型,并通过准静态压缩实验验证了模型的准确性。通过验证的有限元模型,我们证明了ZBSO超材料的多级刚度可以通过改变微观结构(通过在经典的Miura折纸单元胞中引入新的折痕)和改变堆叠方式两种方式有效地定制。利用三种策略来改变微观结构,即在单元格的右侧,左侧或两侧添加新的折痕。我们进一步发现,与传统的机械超材料相比,所提出的ZBSO超材料具有材料无关、尺度不变、轻量化和优异的能量吸收能力等突出优点。ZBSO超材料的优异力学性能为设计具有定制刚度性能的下一代细胞超材料铺平了道路。
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引用次数: 20
Multilayered recoverable sandwich composite structures with architected core 多层可回采夹层复合结构
IF 8.4 Pub Date : 2021-04-25 DOI: 10.1016/j.matdes.2021.110268
V. Damodaran, Anna Hahm, P. Prabhakar
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引用次数: 2
Roadmap for additive manufacturing of HAYNES® 282® superalloy by laser beam powder bed fusion (PBF-LB) technology 采用激光粉末床熔合(PBF-LB)技术的HAYNES®282®高温合金增材制造路线图
IF 8.4 Pub Date : 2021-03-13 DOI: 10.2139/ssrn.3721832
R. Otto, V. Brotan, P. Carvalho, M. Reiersen, J. S. Graff, M. Sunding, O. Å. Berg, S. Diplas, A. Azar
Abstract Although various alloy systems have been explored for additive manufacturing (AM) during the past decade, introducing a new alloy remains a challenging task. Most of the materials require iterative builds, for investigating numerous parameters and determining a viable and repeatable process window. Among the challenging yet highly demanded materials, Haynes 282 superalloy was chosen. It was initially processed through conventional density cube approach, by varying the process parameters for each processed cube. Although the relative densities of the initial builds were not dramatically low, micro-cracks were present in all of them, mostly evolved on a selective number of grain boundaries and spanning only across a single laser path. Detailed modelling and advanced characterization techniques were employed to understand the root cause and cracking mechanism. It was found that the grain boundary precipitates are responsible for crack initiation, amid stress gradient across the grain boundary due to the adjacent grain orientations. Therefore, the failure mechanism is determined as ductility-dip cracking. Based on the findings, a new process window was defined using elevated temperature and novel scanning strategy. No cracks were observed under the modified processing window, meaning that the material can reliably be processed by laser beam powder bed fusion (PBF-LB).
虽然在过去的十年中已经探索了各种合金系统用于增材制造(AM),但引入一种新的合金仍然是一项具有挑战性的任务。大多数材料需要迭代构建,以调查大量参数并确定可行且可重复的过程窗口。在具有挑战性但要求很高的材料中,选择了Haynes 282高温合金。最初通过传统的密度立方体方法进行加工,通过改变每个加工立方体的工艺参数。虽然初始构建的相对密度并不是很低,但所有的微裂纹都存在,大多数是在选择性的晶界上进化而来的,并且只跨越单一的激光路径。采用了详细的建模和先进的表征技术来了解开裂的根本原因和机理。结果表明,晶界析出物是裂纹萌生的主要原因,在晶界上由于邻近晶粒取向而产生应力梯度。因此,确定其破坏机制为延性-倾裂。在此基础上,利用高温和新颖的扫描策略定义了一个新的过程窗口。在改进的加工窗口下,没有观察到裂纹,这意味着该材料可以可靠地进行激光粉末床熔合(PBF-LB)加工。
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引用次数: 19
Design of multi-layered architecture in dissimilar ceramic/metal joints with reinforcements clustering away from both substrates 在不同的陶瓷/金属接头中设计多层结构,增强筋远离两个基板
IF 8.4 Pub Date : 2021-01-15 DOI: 10.1016/j.matdes.2020.109379
Feng Qinghua, Panpan Lin, Guanglu Ma, Tiesong Lin, P. He, W. Long, Zhang Qiuguang
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引用次数: 7
Influence of fiber type on the tensile behavior of high-strength strain-hardening cement-based composites (SHCC) at elevated temperatures 纤维类型对高强应变硬化水泥基复合材料高温拉伸性能的影响
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109397
I. Curosu, M. Liebscher, Sarah Burk, Huanyu Li, S. Hempel, Norbert Raak, H. Rohm, V. Mechtcherine
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引用次数: 22
Laser powder bed fusion additive manufacturing of highly conductive parts made of optically absorptive carburized CuCr1 powder 激光粉末床熔合增材制造光吸收渗碳CuCr1粉末高导电性零件
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109369
S. Jadhav, P. Dhekne, E. Brodu, B. Hooreweder, S. Dadbakhsh, J. Kruth, J. Humbeeck, K. Vanmeensel
{"title":"Laser powder bed fusion additive manufacturing of highly conductive parts made of optically absorptive carburized CuCr1 powder","authors":"S. Jadhav, P. Dhekne, E. Brodu, B. Hooreweder, S. Dadbakhsh, J. Kruth, J. Humbeeck, K. Vanmeensel","doi":"10.1016/j.matdes.2020.109369","DOIUrl":"https://doi.org/10.1016/j.matdes.2020.109369","url":null,"abstract":"","PeriodicalId":101318,"journal":{"name":"MATERIALS & DESIGN","volume":"7 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83353006","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}
引用次数: 42
Programmable shape-shifting 3D structures via frontal photopolymerization 通过正面光聚合可编程变形3D结构
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109381
Jinqiang Wang, Ning Dai, Chengru Jiang, Xiaoming Mu, Biao Zhang, Qi Ge, Dong Wang
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引用次数: 5
A novel solid particle erosion resistant Ti/TiN multilayer coating with additional energy absorbing nano-porous metal layers: Validation by FEM analysis 一种新型的固体颗粒耐蚀Ti/TiN多层涂层,外加吸能纳米多孔金属层:有限元分析验证
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109389
V. Bonu, Sharad Kumar, P. N. Sooraj, H. Barshilia
{"title":"A novel solid particle erosion resistant Ti/TiN multilayer coating with additional energy absorbing nano-porous metal layers: Validation by FEM analysis","authors":"V. Bonu, Sharad Kumar, P. N. Sooraj, H. Barshilia","doi":"10.1016/j.matdes.2020.109389","DOIUrl":"https://doi.org/10.1016/j.matdes.2020.109389","url":null,"abstract":"","PeriodicalId":101318,"journal":{"name":"MATERIALS & DESIGN","volume":"96 1","pages":"109389"},"PeriodicalIF":8.4,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86064951","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}
引用次数: 9
Metal bioaccessibility in synthetic body fluids – A way to consider positive and negative alloying effects in hazard assessments 合成体液中金属的生物可及性。在危害评估中考虑积极和消极合金效应的方法
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109393
Xuying Wang, J. Noël, I. O. Wallinder, Y. Hedberg
{"title":"Metal bioaccessibility in synthetic body fluids – A way to consider positive and negative alloying effects in hazard assessments","authors":"Xuying Wang, J. Noël, I. O. Wallinder, Y. Hedberg","doi":"10.1016/j.matdes.2020.109393","DOIUrl":"https://doi.org/10.1016/j.matdes.2020.109393","url":null,"abstract":"","PeriodicalId":101318,"journal":{"name":"MATERIALS & DESIGN","volume":"2 1","pages":"109393"},"PeriodicalIF":8.4,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79177645","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}
引用次数: 5
The additive manufacture processing and machinability of CrMnFeCoNi high entropy alloy CrMnFeCoNi高熵合金增材制造工艺及可加工性研究
IF 8.4 Pub Date : 2021-01-01 DOI: 10.1016/j.matdes.2020.109380
P. Litwa, E. Hernández-Nava, Dikai Guan, R. Goodall, K. Wika
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引用次数: 24
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