Following the success of 3D printing with synthetic polymers like ABS, FLA, Nylon, etc., scientists and researchers have been putting efforts into fabricating bio-compatible materials. It has not only broadened the field of bioengineering and manufacturing but also regenerative medicine. Unlike the traditional 3D printing process, additive bio-manufacturing, also known as 3D bio-printing has a lot of challenges like cell survivability and proliferation, and the mechanical properties of the biomaterials which involve printability and the ability to hold its structural integrity. Proper design of experiments with extensive rheological investigation can help identify useful mechanical property ranges which are directly related to the geometric fidelity of 3D bio-printed scaffolds. Therefore, to investigate the printability of a low viscosity Alginate-Carboxymethyl Cellulose (CMC), multiple concentrations of the mixture were tested maintaining a 8% (w/v) solid content. A set of rheological tests such as the Steady Rate Sweep Test, Three Point Thixotropic Test (3ITT), and Amplitude test were performed. The outcome of those tests showed that the rheological properties can be controlled with the percentage of CMC in the mixtures. The fabricated filaments and scaffolds in the 5 combinations of CMC percentages were analyzed for flowability and shape fidelity. The rheological results and the printability and shape fidelity results were analyzed.
{"title":"Rheological Analysis of Low Viscosity Hydrogels for 3D Bio-Printing Processes","authors":"Slesha Tuladhar, Cartwright Nelson, A. Habib","doi":"10.1115/msec2021-63658","DOIUrl":"https://doi.org/10.1115/msec2021-63658","url":null,"abstract":"\u0000 Following the success of 3D printing with synthetic polymers like ABS, FLA, Nylon, etc., scientists and researchers have been putting efforts into fabricating bio-compatible materials. It has not only broadened the field of bioengineering and manufacturing but also regenerative medicine. Unlike the traditional 3D printing process, additive bio-manufacturing, also known as 3D bio-printing has a lot of challenges like cell survivability and proliferation, and the mechanical properties of the biomaterials which involve printability and the ability to hold its structural integrity. Proper design of experiments with extensive rheological investigation can help identify useful mechanical property ranges which are directly related to the geometric fidelity of 3D bio-printed scaffolds. Therefore, to investigate the printability of a low viscosity Alginate-Carboxymethyl Cellulose (CMC), multiple concentrations of the mixture were tested maintaining a 8% (w/v) solid content. A set of rheological tests such as the Steady Rate Sweep Test, Three Point Thixotropic Test (3ITT), and Amplitude test were performed. The outcome of those tests showed that the rheological properties can be controlled with the percentage of CMC in the mixtures. The fabricated filaments and scaffolds in the 5 combinations of CMC percentages were analyzed for flowability and shape fidelity. The rheological results and the printability and shape fidelity results were analyzed.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"63 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79248035","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}
A. Chari, Johan Vogt Duberg, E. Lindahl, J. Stahre, M. Despeisse, E. Sundin, B. Johansson, M. Wiktorsson
The Swedish strategic innovation programme, Produktion2030, is a national long-term effort towards global industrial competitiveness addressing Swedish industry’s transition towards climate goals of the European Green Deal while simultaneously realising smart manufacturing and Industry 4.0 (I4.0). This paper investigated the extent of sustainability implementation and implications of I4.0 technologies through a nation-wide quantitative survey in Produktion2030’s 113 collaborative research projects. The analysis showed that 71% of the assessed projects included environmental aspects, 60% social aspects, and 45% Circular Economy (CE) aspects. Further, 65% of the projects implemented I4.0 technologies to increase overall sustainability. The survey results were compared with literature to understand how I4.0 opportunities helped derive sustainability and CE benefits. This detailed mapping of the results along with eight semi-structured interviews revealed that a majority of the projects implemented I4.0 technologies to improve resource efficiency, reduce waste in operations and incorporate CE practices in business models. The results also showed that Swedish manufacturing is progressing in the right direction of sustainability transition by deriving key resilience capabilities from I4.0-based enablers. Industries should actively adopt these capabilities to address the increasingly challenging and unpredictable sustainability issues arising in the world and for a successful transition towards sustainable manufacturing in a digital future.
{"title":"Swedish Manufacturing Practices Towards a Sustainability Transition in Industry 4.0: A Resilience Perspective","authors":"A. Chari, Johan Vogt Duberg, E. Lindahl, J. Stahre, M. Despeisse, E. Sundin, B. Johansson, M. Wiktorsson","doi":"10.1115/msec2021-62394","DOIUrl":"https://doi.org/10.1115/msec2021-62394","url":null,"abstract":"\u0000 The Swedish strategic innovation programme, Produktion2030, is a national long-term effort towards global industrial competitiveness addressing Swedish industry’s transition towards climate goals of the European Green Deal while simultaneously realising smart manufacturing and Industry 4.0 (I4.0). This paper investigated the extent of sustainability implementation and implications of I4.0 technologies through a nation-wide quantitative survey in Produktion2030’s 113 collaborative research projects. The analysis showed that 71% of the assessed projects included environmental aspects, 60% social aspects, and 45% Circular Economy (CE) aspects. Further, 65% of the projects implemented I4.0 technologies to increase overall sustainability. The survey results were compared with literature to understand how I4.0 opportunities helped derive sustainability and CE benefits. This detailed mapping of the results along with eight semi-structured interviews revealed that a majority of the projects implemented I4.0 technologies to improve resource efficiency, reduce waste in operations and incorporate CE practices in business models. The results also showed that Swedish manufacturing is progressing in the right direction of sustainability transition by deriving key resilience capabilities from I4.0-based enablers. Industries should actively adopt these capabilities to address the increasingly challenging and unpredictable sustainability issues arising in the world and for a successful transition towards sustainable manufacturing in a digital future.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78133768","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}
In orthopedic surgery, bone cutting is an indispensable procedure followed by the surgeons to treat the fractured and fragmented bones. Because of the unsuitable parameter values used in the cutting processes, micro crack, fragmentation, and thermal osteonecrosis of bone are observed. Therefore, prediction of suitable cutting force is essential to subtract the bone without any adverse effect. In this study, the Cowper-Symonds model for bovine bone was developed for the first time. Then the developed model was coupled with the finite element analysis to predict the cutting force. To determine the model constants, tensile tests with different strain rates (10−5/s, 10−4/s, 10−3/s, and 1/s) were conducted on the cortical bone specimens. The developed material model was implemented in the bone cutting simulation and validated with the experiments.
{"title":"Prediction of Cutting Force in Bone Cutting Using Finite Element Analysis","authors":"V. Prasannavenkadesan, P. Pandithevan","doi":"10.1115/msec2021-63406","DOIUrl":"https://doi.org/10.1115/msec2021-63406","url":null,"abstract":"\u0000 In orthopedic surgery, bone cutting is an indispensable procedure followed by the surgeons to treat the fractured and fragmented bones. Because of the unsuitable parameter values used in the cutting processes, micro crack, fragmentation, and thermal osteonecrosis of bone are observed. Therefore, prediction of suitable cutting force is essential to subtract the bone without any adverse effect. In this study, the Cowper-Symonds model for bovine bone was developed for the first time. Then the developed model was coupled with the finite element analysis to predict the cutting force. To determine the model constants, tensile tests with different strain rates (10−5/s, 10−4/s, 10−3/s, and 1/s) were conducted on the cortical bone specimens. The developed material model was implemented in the bone cutting simulation and validated with the experiments.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89568433","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}
Sahil Dhoka, Scott W. Wagner, Himansshu Abhi, Nicholas Hendrickson, W. J. Emblom
Reducing fuel consumption has been a driving factor for researchers and manufacturers to continually develop improved methods for reducing the weight of automobiles or lightweighting. These vehicle lightweighting demands have directed researchers to look to using materials that are typically more difficult to manufacture in their studies. As a result, friction stir processing techniques are being looked at more closely. There are advantages to using friction stir methods. Dissimilar metals can be welded and fine-grained products can be created using friction stir methods to name a few. It can be an ideal solution for manufacturing high-conductive metals and alloys. Foamed aluminum tube similar to the one shown by Yoshiko Hangai et al [1] can be formed using the proposed process which could be used to develop lightweight automobile components. This paper provides preliminary results and insights gained when fine metal powders were used in a friction stir back extrusion (FSBE) setup. The tooling consisted of a D2 tool steel die with an H13 rotating probe mounted in a CNC mill. Within the die, commercially pure aluminum powder was topped by an aluminum cap with a milled pocket in the center. This pocket was used to locate the spin tool in the center of the cap and reduce the potential for the tool to drift and deflect. The cap was also used for compacting the powdered aluminum. X-ray diffraction indicated that Al13Fe4 was formed, indicating that the temperature within the die reached a minimum of 800°C and also indicated that the powder had the potential to partially sinter and melt.
{"title":"Integrating Friction-Stir Back Extrusion to Powder Metallurgy","authors":"Sahil Dhoka, Scott W. Wagner, Himansshu Abhi, Nicholas Hendrickson, W. J. Emblom","doi":"10.1115/msec2021-64052","DOIUrl":"https://doi.org/10.1115/msec2021-64052","url":null,"abstract":"\u0000 Reducing fuel consumption has been a driving factor for researchers and manufacturers to continually develop improved methods for reducing the weight of automobiles or lightweighting. These vehicle lightweighting demands have directed researchers to look to using materials that are typically more difficult to manufacture in their studies. As a result, friction stir processing techniques are being looked at more closely. There are advantages to using friction stir methods. Dissimilar metals can be welded and fine-grained products can be created using friction stir methods to name a few. It can be an ideal solution for manufacturing high-conductive metals and alloys. Foamed aluminum tube similar to the one shown by Yoshiko Hangai et al [1] can be formed using the proposed process which could be used to develop lightweight automobile components.\u0000 This paper provides preliminary results and insights gained when fine metal powders were used in a friction stir back extrusion (FSBE) setup. The tooling consisted of a D2 tool steel die with an H13 rotating probe mounted in a CNC mill. Within the die, commercially pure aluminum powder was topped by an aluminum cap with a milled pocket in the center. This pocket was used to locate the spin tool in the center of the cap and reduce the potential for the tool to drift and deflect. The cap was also used for compacting the powdered aluminum. X-ray diffraction indicated that Al13Fe4 was formed, indicating that the temperature within the die reached a minimum of 800°C and also indicated that the powder had the potential to partially sinter and melt.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"83 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88610292","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}
Liangkui Jiang, P. Premaratne, Yanhua Huang, Zhan Zhang, H. Qin
Electrohydrodynamic (EHD) Inkjet printing is one type of micro/nano scale additive manufacturing technique. The droplet generation mechanism plays an important role in electrohydrodynamic (EHD) inkjet printing due to its significant effects on process control, printing quality, and printing performance. The large variation of printing system design used in EHD printing and the limited process optimization techniques resulted in a complex experimental procedure to determine a working condition, and it takes a long time to finish such experiments. It is also challenging to understand the droplet generation mechanism’s fluid dynamics under a multiphysical field in EHD printing. The development of computational fluid dynamics (CFD) and the recent advancements in high performance computing can be utilized to alleviate the aforementioned challenges. In this study, a numerical simulation model was developed to model the droplet generation mechanism in EHD printing based on Taylor-Melchar leaky-dielectric model. This model successfully simulated a single printing cycle, including Taylor cone formation, cone-jet generation, jet break, and jet retraction. A further simulation study demonstrated accurate predictions of the droplet volume and the jetting diameter under different working conditions (e.g., voltages and duty ratio of pulsed AC voltage). Experiments validated the simulation model and its prediction results. Such advancement in modeling can be used to optimize the printing process as well as guide the quick selection of printing conditions given a new ink.
{"title":"Modeling and Experimental Validation of Droplet Generation in Electrohydrodynamic Inkjet Printing for Prediction of Printing Quality","authors":"Liangkui Jiang, P. Premaratne, Yanhua Huang, Zhan Zhang, H. Qin","doi":"10.1115/msec2021-63375","DOIUrl":"https://doi.org/10.1115/msec2021-63375","url":null,"abstract":"\u0000 Electrohydrodynamic (EHD) Inkjet printing is one type of micro/nano scale additive manufacturing technique. The droplet generation mechanism plays an important role in electrohydrodynamic (EHD) inkjet printing due to its significant effects on process control, printing quality, and printing performance. The large variation of printing system design used in EHD printing and the limited process optimization techniques resulted in a complex experimental procedure to determine a working condition, and it takes a long time to finish such experiments. It is also challenging to understand the droplet generation mechanism’s fluid dynamics under a multiphysical field in EHD printing. The development of computational fluid dynamics (CFD) and the recent advancements in high performance computing can be utilized to alleviate the aforementioned challenges. In this study, a numerical simulation model was developed to model the droplet generation mechanism in EHD printing based on Taylor-Melchar leaky-dielectric model. This model successfully simulated a single printing cycle, including Taylor cone formation, cone-jet generation, jet break, and jet retraction. A further simulation study demonstrated accurate predictions of the droplet volume and the jetting diameter under different working conditions (e.g., voltages and duty ratio of pulsed AC voltage). Experiments validated the simulation model and its prediction results. Such advancement in modeling can be used to optimize the printing process as well as guide the quick selection of printing conditions given a new ink.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89307634","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}
The Honeycomb structure is one of the most common natural structures used in sandwich panel cores. The Enamel structure’s mechanical properties were compared to the Honeycomb structure’s mechanical properties to investigate if the Enamel structure can improve the compressive strength, stiffness and energy absorption capabilities of sandwich panel cores and potentially replace the common Honeycomb structure. Also, the optimal cellular configurations for the Honeycomb and Enamel structures were explored. Indeed, it was found the Enamel structure can potentially replace the Honeycomb structure and a wall thickness of 1.2 mm and a wall length/cell radius of 8.14 mm will maximize the natural structures mechanical properties. Furthermore, it was found that both the natural structures have good compressive strength. Therefore, the natural structures with their optimal cellular configurations were integrated into a novel automobile floor mat to ensure the mat possesses good compressive strength to resist failure or permanent deformation. Moreover, the novel automobile floor mat has a design feature that offers an efficient debris capturing and removal system that adds value to the automobile floor mat.
{"title":"Assessing the Mechanical Properties of 3D Printed Bio-Inspired Structures and Integrating Them Into a Product","authors":"Binjamin Perelman, V. Sharma","doi":"10.1115/msec2021-60675","DOIUrl":"https://doi.org/10.1115/msec2021-60675","url":null,"abstract":"\u0000 The Honeycomb structure is one of the most common natural structures used in sandwich panel cores. The Enamel structure’s mechanical properties were compared to the Honeycomb structure’s mechanical properties to investigate if the Enamel structure can improve the compressive strength, stiffness and energy absorption capabilities of sandwich panel cores and potentially replace the common Honeycomb structure. Also, the optimal cellular configurations for the Honeycomb and Enamel structures were explored. Indeed, it was found the Enamel structure can potentially replace the Honeycomb structure and a wall thickness of 1.2 mm and a wall length/cell radius of 8.14 mm will maximize the natural structures mechanical properties.\u0000 Furthermore, it was found that both the natural structures have good compressive strength. Therefore, the natural structures with their optimal cellular configurations were integrated into a novel automobile floor mat to ensure the mat possesses good compressive strength to resist failure or permanent deformation. Moreover, the novel automobile floor mat has a design feature that offers an efficient debris capturing and removal system that adds value to the automobile floor mat.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88493224","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}
Juan Diego Toscano, Sahand Hajifar, Christian Oswaldo Segura, Luis Javier Segura, Hongyue Sun
A cast/brace is a tight garment that restricts the movement and provides support to an injured zone. Traditional casts/braces suffer from material wastage, discomfort, patient dissatisfaction, odor, unnecessary weight, and dangerous extraction procedures. These issues can be solved partially by constructing the casts/braces via 3D printing. Toward this end, we print the personalized metacarpal casts/braces (MCB) via fused deposition modeling (FDM), and investigate their mechanical properties to ensure the desired functionality. However, printing the full-size MCB is time-consuming (takes more than 11 hours in our design), making it hard to collect a sufficient data set for the mechanical properties investigation. Here, we explore the utilization of reduced-size MCB to facilitate the analysis of full-size MCB via transfer learning. In particular, three critical process variables (i.e., raster width, layer height, and extrusion temperature) were varied, and a universal testing machine was used to measure the total deformation of the MCB. We then perform the prediction of the deformation in full-size MCB with transfer learning of data from reduced-size MCB and limited data from full-size MCB. From the case study, the transfer learning approach can reduce the needs of data collection in the time-consuming full-size MCB by leveraging the information from reduced-size MCB.
{"title":"Deformation Analysis of 3D Printed Metacarpophalangeal and Interphalangeal Joints via Transfer Learning","authors":"Juan Diego Toscano, Sahand Hajifar, Christian Oswaldo Segura, Luis Javier Segura, Hongyue Sun","doi":"10.1115/msec2021-63623","DOIUrl":"https://doi.org/10.1115/msec2021-63623","url":null,"abstract":"\u0000 A cast/brace is a tight garment that restricts the movement and provides support to an injured zone. Traditional casts/braces suffer from material wastage, discomfort, patient dissatisfaction, odor, unnecessary weight, and dangerous extraction procedures. These issues can be solved partially by constructing the casts/braces via 3D printing. Toward this end, we print the personalized metacarpal casts/braces (MCB) via fused deposition modeling (FDM), and investigate their mechanical properties to ensure the desired functionality. However, printing the full-size MCB is time-consuming (takes more than 11 hours in our design), making it hard to collect a sufficient data set for the mechanical properties investigation. Here, we explore the utilization of reduced-size MCB to facilitate the analysis of full-size MCB via transfer learning. In particular, three critical process variables (i.e., raster width, layer height, and extrusion temperature) were varied, and a universal testing machine was used to measure the total deformation of the MCB. We then perform the prediction of the deformation in full-size MCB with transfer learning of data from reduced-size MCB and limited data from full-size MCB. From the case study, the transfer learning approach can reduce the needs of data collection in the time-consuming full-size MCB by leveraging the information from reduced-size MCB.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"161 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86791364","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}
Dylan Joralmon, Evangeline A. Amonoo, Yizhen Zhu, Xiangjia Li
Lightweight and cost-effective polymer matrix composites (PMCs) with extraordinary mechanical performance will be a key to the next generation of diverse industrial applications such as aerospace, electric automobile, and biomedical devices. Limpet teeth made of mineral-polymer composites have been proved as nature’s strongest material due to the unique hierarchical architectures of mineral fiber alignment. Here, we present an approach to build limpet teeth inspired structural materials with precise control of geometric morphologies of microstructures by magnetic field-assisted 3D printing (MF-3DP). α-Iron (III) oxide-hydroxide nanoparticles (α-FeOOHs) are aligned by the magnetic field during 3D printing and aligned α-FeOOHs bundles are further grown to aligned goethite-based bundles (aGBs) by rapid thermal treatment after printing. The mechanical reinforcement of goethite-based fillers in PMCs can be modulated by adjusting the geometric morphology and alignment of mineral particles encapsulated inside the 3D printed PMCs. In order to identify the mechanical enhancement mechanism, physics-based modeling, simulation, and tests were conducted and the results further guided the design of bioinspired goethite-based PMCs. The correlation of the geometric morphology of self-assembled α-FeOOHs, curing characteristics of α-FeOOHs/polymer composite, and process parameters were identified to establish the optimal design of goethite-based PMCs. The 3D-printed PMCs with aGBs show promising mechanical reinforcement. This study opens intriguing perspectives for designing high strength 3D printed PMCs on the basis of bioinspired architectures with customized configurations.
{"title":"Magnetic Field Assisted 3D Printing of Limpet Teeth Inspired Polymer Matrix Composite With Compression Reinforcement","authors":"Dylan Joralmon, Evangeline A. Amonoo, Yizhen Zhu, Xiangjia Li","doi":"10.1115/msec2021-61050","DOIUrl":"https://doi.org/10.1115/msec2021-61050","url":null,"abstract":"\u0000 Lightweight and cost-effective polymer matrix composites (PMCs) with extraordinary mechanical performance will be a key to the next generation of diverse industrial applications such as aerospace, electric automobile, and biomedical devices. Limpet teeth made of mineral-polymer composites have been proved as nature’s strongest material due to the unique hierarchical architectures of mineral fiber alignment. Here, we present an approach to build limpet teeth inspired structural materials with precise control of geometric morphologies of microstructures by magnetic field-assisted 3D printing (MF-3DP). α-Iron (III) oxide-hydroxide nanoparticles (α-FeOOHs) are aligned by the magnetic field during 3D printing and aligned α-FeOOHs bundles are further grown to aligned goethite-based bundles (aGBs) by rapid thermal treatment after printing. The mechanical reinforcement of goethite-based fillers in PMCs can be modulated by adjusting the geometric morphology and alignment of mineral particles encapsulated inside the 3D printed PMCs. In order to identify the mechanical enhancement mechanism, physics-based modeling, simulation, and tests were conducted and the results further guided the design of bioinspired goethite-based PMCs. The correlation of the geometric morphology of self-assembled α-FeOOHs, curing characteristics of α-FeOOHs/polymer composite, and process parameters were identified to establish the optimal design of goethite-based PMCs. The 3D-printed PMCs with aGBs show promising mechanical reinforcement. This study opens intriguing perspectives for designing high strength 3D printed PMCs on the basis of bioinspired architectures with customized configurations.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85372505","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}
With an end goal of creating single-alloy functionally-graded additively manufactured (FGAM) parts, this paper investigates the manufacture and properties of stainless steel 316L samples via a pulsed selective laser melting (SLM) process. The focus is on elucidating the underlying causes of property variations (within a functionally-acceptable range) through material characterization and testing. Five samples (made via different volumetric energy density-based process parameter sets) were down-selected from preliminary experimental results and analyzed for their microstructure, mechanical and physical properties (hardness, density/porosity, Young’s modulus). It was observed that property variations resulted from combinations of porosity types/amounts, martensitic phase fractions, and grain sizes. Based on these, various functionally-graded specimens of different sizes were built as per ASTM standards, each having intended property changes along its gauge volumes. The presented findings establish that a methodical control of microstructure and mechanical properties could be obtained in a repeatable and reproducible manner by changing the process parameters. This work lays the foundation for understanding and tuning the global mechanical performance of FGAM bulk structures as well as the role of interfacial zones.
{"title":"Selective Laser Melting of Stainless Steel 316L for Mechanical Property-Gradation","authors":"Yash Parikh, Mathew Kuttolamadom","doi":"10.1115/msec2021-64108","DOIUrl":"https://doi.org/10.1115/msec2021-64108","url":null,"abstract":"\u0000 With an end goal of creating single-alloy functionally-graded additively manufactured (FGAM) parts, this paper investigates the manufacture and properties of stainless steel 316L samples via a pulsed selective laser melting (SLM) process. The focus is on elucidating the underlying causes of property variations (within a functionally-acceptable range) through material characterization and testing. Five samples (made via different volumetric energy density-based process parameter sets) were down-selected from preliminary experimental results and analyzed for their microstructure, mechanical and physical properties (hardness, density/porosity, Young’s modulus). It was observed that property variations resulted from combinations of porosity types/amounts, martensitic phase fractions, and grain sizes. Based on these, various functionally-graded specimens of different sizes were built as per ASTM standards, each having intended property changes along its gauge volumes. The presented findings establish that a methodical control of microstructure and mechanical properties could be obtained in a repeatable and reproducible manner by changing the process parameters. This work lays the foundation for understanding and tuning the global mechanical performance of FGAM bulk structures as well as the role of interfacial zones.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76478786","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}
Iron has appealing biodegradable properties that makes compatible for biodegradable implant tools applications. Although, the slow corrosion rate of Fe made obsolete for biomedical applications. The incorporation of the porous structure may result in an enhanced degradation rate. The main advantage offer by the porous structure is to allow to flow the body transportation fluid through it and ease to proliferate the new tissue. Therefore, the current work focused on the development of a porous Fe structures using micro-extrusion based three-dimensional printing (ME3DP) and pressure less microwave sintering. The metallic-based polymeric ink used to fabricate the intent design structure. Subsequently, samples were heated in the microwave sintering furnace. The experimentations were done to evaluate the outcomes of different Fe concentrations (91–95 wt.%) on density and compressive yield strength of developed porous parts. Experimental observation deduced that fabricated part ≥ 94.wt.% of Fe concentration has strong bonding strength between the printed layers. Moreover, the mechanical property of 94 wt.% has found greater than 95 wt.% of Fe concentration. The scanning electron microscopic (SEM) image illustrated the presence of porous morphology into the fabricated body. Additionally, XRD (X-ray diffraction) plots exhibited the purity of sample without any contamination residue.
{"title":"Experimental Investigation Into the Fabrication of Porous Biodegradable Fe Scaffold by Microwave Sintering of 3D Printed Green Body","authors":"D. Mishra, P. M. Pandey","doi":"10.1115/msec2021-63402","DOIUrl":"https://doi.org/10.1115/msec2021-63402","url":null,"abstract":"\u0000 Iron has appealing biodegradable properties that makes compatible for biodegradable implant tools applications. Although, the slow corrosion rate of Fe made obsolete for biomedical applications. The incorporation of the porous structure may result in an enhanced degradation rate. The main advantage offer by the porous structure is to allow to flow the body transportation fluid through it and ease to proliferate the new tissue. Therefore, the current work focused on the development of a porous Fe structures using micro-extrusion based three-dimensional printing (ME3DP) and pressure less microwave sintering. The metallic-based polymeric ink used to fabricate the intent design structure. Subsequently, samples were heated in the microwave sintering furnace. The experimentations were done to evaluate the outcomes of different Fe concentrations (91–95 wt.%) on density and compressive yield strength of developed porous parts. Experimental observation deduced that fabricated part ≥ 94.wt.% of Fe concentration has strong bonding strength between the printed layers. Moreover, the mechanical property of 94 wt.% has found greater than 95 wt.% of Fe concentration. The scanning electron microscopic (SEM) image illustrated the presence of porous morphology into the fabricated body. Additionally, XRD (X-ray diffraction) plots exhibited the purity of sample without any contamination residue.","PeriodicalId":56519,"journal":{"name":"光:先进制造(英文)","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73212755","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}
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