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Assessing the Feasibility of Fabricating Thermoplastic Laminates from Unidirectional Tapes in Open Mold Environments 评估在开放式模具环境中利用单向带制造热塑性层压板的可行性
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-06 DOI: 10.3390/jmmp8010012
Basit Ali, Khaled Kadri, M. Alkhader, W. Abuzaid, Mohammad A. Jaradat, Mohammed Mustafa, Mohamed Hassanien
The automation of the manufacturing processes of thermoplastic composite laminates has become dependent on open mold processes such as automated tape placement (ATP), which couples tape layering with in situ consolidation. The manufacturing parameters of ATP open mold processes, which comprise processing time, consolidation pressure and temperature, affect the bond strength between the plies and the quality of the laminates produced. Therefore, the effect of the manufacturing parameters should be characterized. This work experimentally evaluates the feasibility of fabricating thermoplastic laminates using an open mold process that reasonably models that of ATP. Glass fiber-reinforced polypropylene laminates are fabricated from unidirectional tapes under different consolidation periods, pressures, and temperatures. The bond quality in the produced laminates is assessed by measuring their interlaminar shear strength, which is measured using a short beam standardized shear test in conjunction with digital image correlation. Results show that consolidation can occur at temperatures slightly below the composite tapes’ complete melting temperature, and consolidation times between 7 and 13 min can result in acceptable bond strengths. The results confirmed the feasibility of the process and highlighted its limitations. Analysis of variance and machine learning showed that the effect of process parameters on interlaminar shear strength is nonlinear.
热塑性复合材料层压板生产工艺的自动化依赖于开模工艺,如自动胶带铺放(ATP),该工艺将胶带分层与原位固结结合在一起。ATP 开模工艺的制造参数(包括加工时间、固结压力和温度)会影响层间的粘结强度和所生产层压板的质量。因此,应确定制造参数的影响。这项工作通过实验评估了使用合理模拟 ATP 的开放式模具工艺制造热塑性层压板的可行性。在不同的固结期、压力和温度条件下,用单向带制造玻璃纤维增强聚丙烯层压板。通过测量层间剪切强度来评估所生产层压板的粘合质量。结果表明,在略低于复合材料带完全熔化温度的情况下就能发生固结,固结时间在 7 至 13 分钟之间,可产生可接受的粘结强度。结果证实了该工艺的可行性,并强调了其局限性。方差分析和机器学习表明,工艺参数对层间剪切强度的影响是非线性的。
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引用次数: 0
Vickers Hardness Mechanical Models and Thermoplastic Polymer Injection-Molded Products’ Static Friction Coefficients 维氏硬度力学模型和热塑性聚合物注塑产品的静摩擦系数
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-05 DOI: 10.3390/jmmp8010011
Tetsuo Takayama
The surface mechanical properties of thermoplastics are crucially important for evaluating molded products’ vulnerability to scratching. Because surface mechanical properties reflect material performance directly in terms of durability and frictional behavior, understanding and modeling them is important for industry and research. This emphasizes the surface mechanical properties of Vickers hardness and the static friction coefficient, with attempts to model them as functions of stress at yield initiation. Vickers hardness can be related to the compressive stress at yield initiation. The static friction coefficient can be modeled as a function of the surface shear strength and Vickers hardness. This research has improved our understanding of thermoplastics’ surface mechanical properties and has enabled the prediction of the scratch performance of molded products and the provision of effective indicators for material design.
热塑性塑料的表面机械性能对于评估成型产品是否易受划伤至关重要。由于表面机械性能直接反映了材料的耐久性和摩擦行为,因此了解这些性能并对其进行建模对于工业和研究都非常重要。本研究强调维氏硬度和静摩擦系数的表面机械特性,并尝试将它们作为屈服开始时的应力函数进行建模。维氏硬度可与屈服开始时的压缩应力相关联。静摩擦系数可作为表面剪切强度和维氏硬度的函数建模。这项研究提高了我们对热塑性塑料表面机械性能的认识,从而能够预测成型产品的划痕性能,并为材料设计提供有效指标。
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引用次数: 0
Phase Composition, Microstructure and Mechanical Properties of Zr57Cu15Ni10Nb5 Alloy Obtained by Selective Laser Melting 通过选择性激光熔化获得的 Zr57Cu15Ni10Nb5 合金的相组成、显微结构和力学性能
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-04 DOI: 10.3390/jmmp8010010
R. Khmyrov, A. Korotkov, M. Gridnev, P. Podrabinnik, Tatiana V. Tarasova, Andrey V. Gusarov
Zr57Cu15Ni10Nb5 (more known as Vit-106) is a promising zirconium-based alloy with a high glass-forming ability, and belongs to the so-called bulk metallic glasses (BMG). Workpieces with a size of around one centimeter in all three dimensions can be obtained from a BMG alloy by casting. However, further increasing the cast size decreases the cooling rate and thus induces crystallization. Selective laser melting (SLM) is a well-known technique to overcome size limitations for BMGs because a workpiece is built by the addition of multiple melt portions in which the cooling rate is kept above the critical one. Currently, BMG parts obtained by SLM suffer from partial crystallization. The present work studies the influence of SLM process parameters on the partial crystallization of Vit-106 by metallography and the influence of the microstructure on mechanical properties by microhardness and wear resistance testing. Submicron crystalline inclusions are observed in an amorphous matrix of a Vit-106 alloy obtained by SLM. The size and the concentration of the inclusions can be controlled by varying the laser scanning speed. It is shown that submicron crystalline inclusions formed in the amorphous matrix during SLM can favorably affect microhardness and wear resistance.
Zr57Cu15Ni10Nb5(又称 Vit-106)是一种前景看好的锆基合金,具有很高的玻璃化能力,属于所谓的块状金属玻璃(BMG)。BMG 合金可通过铸造获得三维尺寸均在一厘米左右的工件。然而,进一步增大铸件尺寸会降低冷却速度,从而导致结晶。选择性激光熔化(SLM)是一种众所周知的克服 BMG 尺寸限制的技术,因为工件是由多个熔体部分组成的,其中的冷却速率保持在临界速率以上。目前,通过 SLM 获得的 BMG 零件存在部分结晶的问题。本研究通过金相学研究了 SLM 工艺参数对 Vit-106 部分结晶的影响,并通过显微硬度和耐磨性测试研究了微观结构对机械性能的影响。在通过 SLM 获得的 Vit-106 合金的无定形基体中观察到了亚微米结晶夹杂物。夹杂物的大小和浓度可通过改变激光扫描速度来控制。结果表明,在 SLM 过程中在无定形基体中形成的亚微米晶体夹杂物会对显微硬度和耐磨性产生有利影响。
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引用次数: 0
In-Process Machining Distortion Prediction Method Based on Bulk Residual Stresses Estimation from Reduced Layer Removal 基于减层去除的块状残余应力估算的序中加工变形预测方法
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-03 DOI: 10.3390/jmmp8010009
M. Aurrekoetxea, Luis Norberto López de Lacalle, O. Zelaieta, I. Llanos
Manufacturing structural monolithic components for the aerospace market often involves machining distortion, which entails high costs and material and energy waste in industry. Despite the development of distortion calculation and avoidance tools, this issue remains unsolved due to the difficulties in accurately and economically measuring the residual stresses of the machining blanks. In the last years, the on-machine layer removal method has shown its potential for industrial implementation, offering the possibility to obtain final components from blanks with measured residual stresses. However, this measuring method requires too long an implementation time to be used in-process as part of the manufacturing chains. In this sense, the objective of this paper is to provide a machining distortion prediction method based on bulk residual stress estimation and hybrid modelling. The bulk residual stresses estimation is performed using reduced layer removal measurements. Considering bulk residual stress data and machining-induced residual stress data, as well as geometry and material data, real-part distortion calculations can be performed. For this, a hybrid model based on the combination of an analytical formulation and finite element modelling is employed, which enables us to perform fast and accurate calculations. With the developments here presented, the machining distortion can be predicted, and its uncertainty range can be calculated, in a simple and fast way. The accuracy and practicality of these developments are evaluated by comparison with the experimental results, showing the capability of the proposed solution in providing distortion predictions with errors lower than 10% in comparison with the experimental results.
为航空航天市场制造整体结构部件往往会产生加工变形,这给工业带来了高昂的成本以及材料和能源浪费。尽管已开发出变形计算和避免工具,但由于难以准确、经济地测量加工坯料的残余应力,这一问题仍未得到解决。在过去的几年中,机上去层方法已经显示出其在工业应用方面的潜力,为从测量残余应力的坯料中获得最终部件提供了可能性。然而,这种测量方法需要较长的实施时间,无法作为制造链的一部分在加工过程中使用。从这个意义上说,本文的目的是提供一种基于体残余应力估算和混合建模的加工变形预测方法。批量残余应力估算是通过减少层去除测量来进行的。考虑到整体残余应力数据和加工引起的残余应力数据,以及几何和材料数据,可以进行实际零件变形计算。为此,我们采用了一种基于分析表述和有限元建模相结合的混合模型,使我们能够进行快速而精确的计算。通过本文介绍的开发成果,可以简单快速地预测加工变形并计算其不确定性范围。通过与实验结果的对比,我们评估了这些开发成果的准确性和实用性,结果表明,与实验结果相比,所提出的解决方案能够提供误差低于 10%的变形预测。
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引用次数: 0
Mesoscale Simulation of Laser Powder Bed Fusion with an Increased Layer Thickness for AlSi10Mg Alloy 增加层厚的 AlSi10Mg 合金激光粉末床熔化中尺度模拟
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-01 DOI: 10.3390/jmmp8010007
Maria Bogdanova, S. Chernyshikhin, Andrey Zakirov, B. Zotov, Leonid Fedorenko, Sergei Belousov, A. Perepelkina, Boris Korneev, Maria Lyange, Ivan Pelevin, Inna Iskandarova, Ella Dzidziguri, Boris Potapkin, Alexander Gromov
Low performance is considered one of the main drawbacks of laser powder bed fusion (LPBF) technology. In the present work, the effect of the AlSi10Mg powder layer thickness on the laser melting process was investigated to improve the LPBF building rate. A high-fidelity simulation of the melt pool formation was performed for different thicknesses of the powder bed using the Kintech Simulation Software for Additive Manufacturing (KiSSAM, version cd8e01d) developed by the authors. The powder bed after the recoating operation was obtained by the discrete element method. The laser energy deposition on the powder particles and the substrate was simulated by ray tracing. For the validation of the model, an experimental analysis of single tracks was performed on two types of substrates. The first substrate was manufactured directly with LPBF technology, while the second was cast. The simulation was carried out for various combinations of process parameters, predominantly with a high energy input, which provided a sufficient remelting depth. The calculations revealed the unstable keyhole mode appearance associated with the low absorptivity of the aluminum alloy at a scanning speed of 300 mm/s for all levels of the laser power (325–375 W). The results allowed formulating the criteria for the lack of fusion emerging during LPBF with an increased layer thickness. This work is expected to provide a scientific basis for the analysis of the maximum layer thickness via simulation to increase the performance of the technology.
性能低下是激光粉末床熔融(LPBF)技术的主要缺点之一。在本研究中,研究了 AlSi10Mg 粉末层厚度对激光熔化过程的影响,以提高 LPBF 的成型率。利用作者开发的 Kintech 增材制造模拟软件(KiSSAM,版本 cd8e01d),对不同厚度的粉末床进行了熔池形成的高保真模拟。重涂操作后的粉末床是通过离散元法得到的。激光能量在粉末颗粒和基底上的沉积是通过射线追踪模拟的。为了验证模型,在两种基底上进行了单轨实验分析。第一种基板是用 LPBF 技术直接制造的,而第二种基板是铸造的。模拟是针对各种工艺参数组合进行的,主要是高能量输入,以提供足够的重熔深度。计算结果表明,在扫描速度为 300 毫米/秒、激光功率为 325-375 瓦的情况下,不稳定的锁孔模式出现与铝合金的低吸收率有关。这些结果有助于制定 LPBF 在增加层厚度时出现不熔合的标准。这项工作有望为通过模拟分析最大层厚提供科学依据,从而提高该技术的性能。
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引用次数: 0
Quality Prediction and Classification of Process Parameterization for Multi-Material Jetting by Means of Computer Vision and Machine Learning 利用计算机视觉和机器学习对多材料喷射工艺参数化进行质量预测和分类
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-01 DOI: 10.3390/jmmp8010008
Armin Reckert, Valentin Lang, Steven Weingarten, Robert Johne, Jan-Hendrik Klein, Steffen Ihlenfeldt
Multi-Material Jetting (MMJ) is an additive manufacturing process empowering the printing of ceramics and hard metals with the highest precision. Given great advantages, it also poses challenges in ensuring the repeatability of part quality due to an inherent broader choice of built strategies. The addition of advanced quality assurance methods can therefore benefit the repeatability of part quality for widespread adoption. In particular, quality defects caused by improperly configured droplet overlap parameterizations, despite droplets themselves being well parameterized, constitute a major challenge for stable process control. This publication deals with the automated classification of the adequacy of process parameterization on green parts based on in-line surface measurements and their processing with machine learning methods, in particular the training of convolutional neural networks. To generate the training data, a demo part structure with eight layers was printed with different overlap settings, scanned, and labeled by process engineers. In particular, models with two convolutional layers and a pooling size of (6, 6) appeared to yield the best accuracies. Models trained only with images of the first layer and without the infill edge obtained validation accuracies of 90%. Consequently, an arbitrary section of the first layer is sufficient to deliver a prediction about the quality of the subsequently printed layers.
多材料喷射(MMJ)是一种快速成型制造工艺,能够以最高精度打印陶瓷和硬金属。虽然它具有很大的优势,但由于其固有的制造策略选择范围更广,因此也给确保零件质量的可重复性带来了挑战。因此,增加先进的质量保证方法有利于提高零件质量的可重复性,从而实现广泛应用。特别是,尽管液滴本身的参数设置良好,但由于液滴重叠参数配置不当而导致的质量缺陷,对稳定的过程控制构成了重大挑战。本刊物介绍了基于在线表面测量和机器学习方法(特别是卷积神经网络的训练)对绿色部件工艺参数化的适当性进行自动分类的方法。为了生成训练数据,我们使用不同的重叠设置打印了一个具有八层结构的演示零件,对其进行了扫描,并由工艺工程师进行了标注。其中,具有两个卷积层和池化大小为(6,6)的模型似乎产生了最好的准确度。仅使用第一层图像且不使用填充边缘的模型可获得 90% 的验证准确率。因此,第一层的任意部分都足以预测后续印刷层的质量。
{"title":"Quality Prediction and Classification of Process Parameterization for Multi-Material Jetting by Means of Computer Vision and Machine Learning","authors":"Armin Reckert, Valentin Lang, Steven Weingarten, Robert Johne, Jan-Hendrik Klein, Steffen Ihlenfeldt","doi":"10.3390/jmmp8010008","DOIUrl":"https://doi.org/10.3390/jmmp8010008","url":null,"abstract":"Multi-Material Jetting (MMJ) is an additive manufacturing process empowering the printing of ceramics and hard metals with the highest precision. Given great advantages, it also poses challenges in ensuring the repeatability of part quality due to an inherent broader choice of built strategies. The addition of advanced quality assurance methods can therefore benefit the repeatability of part quality for widespread adoption. In particular, quality defects caused by improperly configured droplet overlap parameterizations, despite droplets themselves being well parameterized, constitute a major challenge for stable process control. This publication deals with the automated classification of the adequacy of process parameterization on green parts based on in-line surface measurements and their processing with machine learning methods, in particular the training of convolutional neural networks. To generate the training data, a demo part structure with eight layers was printed with different overlap settings, scanned, and labeled by process engineers. In particular, models with two convolutional layers and a pooling size of (6, 6) appeared to yield the best accuracies. Models trained only with images of the first layer and without the infill edge obtained validation accuracies of 90%. Consequently, an arbitrary section of the first layer is sufficient to deliver a prediction about the quality of the subsequently printed layers.","PeriodicalId":16319,"journal":{"name":"Journal of Manufacturing and Materials Processing","volume":"49 24","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139125489","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: 0
A Combined Microscopy Study of the Microstructural Evolution of Ferritic Stainless Steel upon Deep Drawing: The Role of Alloy Composition 铁素体不锈钢深拉时微结构演变的组合显微镜研究:合金成分的作用
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2024-01-01 DOI: 10.3390/jmmp8010006
A. Núñez, I. Collado, M. de la Mata, Juan F. Almagro, David L. Sales
Ferritic stainless steel (FSS) is widely used to manufacture deep-drawn products for corrosion resistance applications, being the alloy drawability strongly affected by its microstructural anisotropy. This study combines a variety of microscopy techniques enabling in-depth analyses of the microstructural evolution of two different FSSs correlated to their deep drawing performance. One of the steels has a good correspondence with the standard EN-1.4016 (AISI 430). The other is a modified version of the previous one with higher contents of the ferrite-stabilising elements Si and Cr, and lower contents of the austenite-stabilising elements C, N, and Mn. Electron Backscatter Diffraction results confirm that the microstructural properties and drawability of FSS in the deep drawing process are improved in the modified steel version. Scanning transmission electron microscopy under low-angle annular dark field conditions evidences that the deformation mechanism of FSS during deep drawing follows a microstructural distortion model based on the grain size gradient and shows a variation of the deformation texture depending on the alloy composition. This work demonstrates the potential of advanced microscopy techniques for optimising the processing and design of ferritic stainless steels, with slight variations in the alloy composition, for deep drawing applications.
铁素体不锈钢(FSS)被广泛用于制造耐腐蚀深冲产品,其合金的可拉伸性受其微观结构各向异性的影响很大。本研究结合多种显微镜技术,深入分析了两种不同 FSS 的微观结构演变与其深拉性能的相关性。其中一种钢与 EN-1.4016 标准(AISI 430)有很好的对应关系。另一种是前一种的改进型,铁素体稳定元素 Si 和 Cr 含量较高,奥氏体稳定元素 C、N 和 Mn 含量较低。电子反向散射衍射结果证实,改良钢在深拉工艺中的微观结构特性和 FSS 的可拉伸性得到了改善。低角度环形暗场条件下的扫描透射电子显微镜证明,FSS 在深拉过程中的变形机制遵循基于晶粒尺寸梯度的微结构变形模型,并显示出变形纹理随合金成分而变化。这项工作表明,先进的显微镜技术具有优化铁素体不锈钢加工和设计的潜力,合金成分略有不同的铁素体不锈钢可用于深冲压应用。
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引用次数: 0
Analysis of Machinability on Properties of Inconel 718 Wire and Arc Additive Manufacturing Products 可加工性对铬镍铁合金 718 线材和电弧增材制造产品性能的影响分析
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2023-12-25 DOI: 10.3390/jmmp8010004
Gustavo Quadra Vieira dos Santos, Jun’ichi Kaneko, Takeyuki Abe
Wire and arc additive manufacturing (WAAM) is a metal deposition technique with a fast rate and the possibility of a high volume of deposition. Because of its fast deposition and high heat input, the manufactured products have poor surface quality. This paper presents a study on the machining of Inconel 718 wall-shaped additive manufacturing (AM) products, a necessary step for the improvement of surface quality. Considering the possibility that the characteristics of the milling processes of AM products might differ from those of traditionally manufactured parts, in this research, two types of Inconel 718 were studied and compared: one was manufactured using WAAM, and the other was an Inconel 718 rolled bar (Aerospace Material Specifications 5662). Using the testing procedure, a conventional two-flute cutting tool was used to assess their machinability. For this process, multiple passes were performed at three different heights of the samples. Considering the peculiarities of the AM products, such as their uneven surfaces, dendritic microstructures, and anisotropy, the results were analyzed. After the machining operation, the effects on the products were also studied by analyzing their surface quality. This study found a higher stability in the cutting process for the AMS 5662 samples relative to the WAAM parts with less variability in the cutting forces overall, resulting in better surface quality.
线弧增材制造(WAAM)是一种金属沉积技术,具有速度快、沉积量大的特点。由于其沉积速度快、输入热量高,因此制造出的产品表面质量较差。本文对 Inconel 718 壁形增材制造(AM)产品的加工进行了研究,这是提高表面质量的必要步骤。考虑到 AM 产品的铣削加工特性可能不同于传统制造的零件,本研究对两种类型的 Inconel 718 进行了研究和比较:一种是使用 WAAM 制造的,另一种是 Inconel 718 轧制棒材(航空材料规格 5662)。通过测试程序,使用传统的双刃切削工具来评估它们的可加工性。在此过程中,对样品的三个不同高度进行了多次加工。考虑到 AM 产品的特殊性,如表面不平整、树枝状微结构和各向异性,对结果进行了分析。加工操作结束后,还通过分析表面质量研究了对产品的影响。研究发现,与 WAAM 零件相比,AMS 5662 样品在切削过程中的稳定性更高,切削力的总体变化更小,因此表面质量更好。
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引用次数: 0
Numerical Modelling for Efficient Analysis of Large Size Multi-Stage Incremental Sheet Forming 用于高效分析大型多级增量板材成型的数值模型
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2023-12-22 DOI: 10.3390/jmmp8010003
Yehia A. Abdel-Nasser, Ninshu Ma, Sherif Rashed, Kenji Miyamoto, Hirotaka Miwa
Incremental sheet forming (ISF) is an advanced flexible manufacturing process to produce complex 3D products. Unlike the conventional stamping process, ISF does not require any high cost dedicated dies. However, numerical computation for large-size ISF processes is time-consuming, and its accuracy for spring back due to unclamping tools after ISF cannot satisfy industrial demand. In this paper, an advanced numerical model considering complicated forming tool paths, trimming, and spring back was developed to efficiently simulate the multi-stage deformation phenomena of incremental sheet forming processes. Numerical modeling accuracy and efficiency are investigated considering the influence of tool path, material properties of the blank, mesh size, and boundary conditions. Through a series of case studies and comparisons with experimental results, it is observed that the numerical model with kinematics material properties and a moderate element size (5 mm) may reproduce the deformation characteristics of ISF with good accuracy and can obtain practical efficiency for a large-size ISF part.
增量式板材成型(ISF)是一种先进的柔性制造工艺,用于生产复杂的三维产品。与传统的冲压工艺不同,ISF 不需要任何高成本的专用模具。然而,大尺寸 ISF 工艺的数值计算耗时较长,而且其对 ISF 后因工具松开而产生的回弹的精度也无法满足工业需求。本文开发了一种先进的数值模型,该模型考虑了复杂的成形刀具路径、修剪和回弹,可有效模拟增量式板材成形过程的多阶段变形现象。考虑到工具路径、坯料材料属性、网格尺寸和边界条件的影响,研究了数值建模的精度和效率。通过一系列案例研究以及与实验结果的比较,可以看出具有运动学材料属性和适中元素尺寸(5 毫米)的数值模型可以很好地再现 ISF 的变形特征,并能为大尺寸 ISF 零件带来实用效率。
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引用次数: 0
Three-Dimensional Printing of Biomass–Fungi Biocomposite Materials: The Effects of Mixing and Printing Parameters on Fungal Growth 生物质-真菌生物复合材料的三维印刷:混合和印刷参数对真菌生长的影响
IF 3.2 Q2 ENGINEERING, MANUFACTURING Pub Date : 2023-12-19 DOI: 10.3390/jmmp8010002
Al Mazedur Rahman, A. Bhardwaj, Joseph G. Vasselli, Zhijian Pei, Brian D. Shaw
Biomass–fungi biocomposite materials are derived from sustainable sources and can biodegrade at the end of their service. They can be used to manufacture products that are traditionally made from petroleum-based plastics. There are potential applications for these products in the packaging, furniture, and construction industries. In the biomass–fungi biocomposite materials, the biomass particles (made from agricultural waste such as hemp hurd) act as the substrate, and a network of fungal hyphae grow through and bind the biomass particles together. Typically, molding-based methods are used to manufacture products using these biocomposite materials. Recently, the authors reported a novel extrusion-based 3D printing method using these biocomposite materials. This paper reports a follow-up investigation into the effects of mixing parameters (mixing time and mixing mode) on fungal growth in biomass–fungi mixtures prepared for 3D printing and the effects of printing parameters (printing speed and extrusion pressure) on fungal growth in printed samples. The fungal growth was quantified using the number of fungal colonies that grew from samples. The results show that, when mixing time increased from 15 to 120 s, there was a 52% increase in fungal growth. Changing from continuous to intermittent mixing mode resulted in an 11% increase in fungal growth. Compared to mixtures that were not subjected to printing, samples printed with a high printing speed and high extrusion pressure had a 14.6% reduction in fungal growth, while those with a low printing speed and low extrusion pressure resulted in a 16.5% reduction in fungal growth.
生物质-真菌生物复合材料来源于可持续发展的资源,并可在使用期结束后进行生物降解。它们可用于制造传统上由石油基塑料制成的产品。这些产品有可能应用于包装、家具和建筑行业。在生物质-真菌生物复合材料中,生物质颗粒(由大麻等农业废弃物制成)作为基材,真菌菌丝网络穿过生物质颗粒并将其粘合在一起。使用这些生物复合材料制造产品时,通常采用成型方法。最近,作者报道了一种使用这些生物复合材料的新型挤压式 3D 打印方法。本文报告了混合参数(混合时间和混合模式)对用于三维打印的生物质-真菌混合物中真菌生长的影响,以及打印参数(打印速度和挤出压力)对打印样品中真菌生长的影响。真菌生长的数量是通过从样品中生长出的真菌菌落数量来量化的。结果显示,当混合时间从 15 秒增加到 120 秒时,真菌生长增加了 52%。将连续混合模式改为间歇混合模式后,真菌生长量增加了 11%。与未进行印刷的混合物相比,采用高印刷速度和高挤出压力印刷的样品,真菌生长减少了 14.6%,而采用低印刷速度和低挤出压力印刷的样品,真菌生长减少了 16.5%。
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引用次数: 0
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