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Marupudi S, Cao Q, Samala R, Petrick N. Characterization of mechanical stiffness using additive manufacturing and finite element analysis: potential tool for bone health assessment. 3D Print Med 2023; 9:32. [PMID: 37978094 PMCID: PMC10656885 DOI: 10.1186/s41205-023-00197-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND Bone health and fracture risk are known to be correlated with stiffness. Both micro-finite element analysis (μFEA) and mechanical testing of additive manufactured phantoms are useful approaches for estimating mechanical properties of trabecular bone-like structures. However, it is unclear if measurements from the two approaches are consistent. The purpose of this work is to evaluate the agreement between stiffness measurements obtained from mechanical testing of additive manufactured trabecular bone phantoms and μFEA modeling. Agreement between the two methods would suggest 3D printing is a viable method for validation of μFEA modeling. METHODS A set of 20 lumbar vertebrae regions of interests were segmented and the corresponding trabecular bone phantoms were produced using selective laser sintering. The phantoms were mechanically tested in uniaxial compression to derive their stiffness values. The stiffness values were also derived from in silico simulation, where linear elastic μFEA was applied to simulate the same compression and boundary conditions. Bland-Altman analysis was used to evaluate agreement between the mechanical testing and μFEA simulation values. Additionally, we evaluated the fidelity of the 3D printed phantoms as well as the repeatability of the 3D printing and mechanical testing process. RESULTS We observed good agreement between the mechanically tested stiffness and μFEA stiffness, with R2 of 0.84 and normalized root mean square deviation of 8.1%. We demonstrate that the overall trabecular bone structures are printed in high fidelity (Dice score of 0.97 (95% CI, [0.96,0.98]) and that mechanical testing is repeatable (coefficient of variation less than 5% for stiffness values from testing of duplicated phantoms). However, we noticed some defects in the resin microstructure of the 3D printed phantoms, which may account for the discrepancy between the stiffness values from simulation and mechanical testing. CONCLUSION Overall, the level of agreement achieved between the mechanical stiffness and μFEA indicates that our μFEA methods may be acceptable for assessing bone mechanics of complex trabecular structures as part of an analysis of overall bone health.
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Affiliation(s)
- Sriharsha Marupudi
- Division of Imaging, Diagnostics, and Software Reliability, Office of Science and Engineering Labs, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Qian Cao
- Division of Imaging, Diagnostics, and Software Reliability, Office of Science and Engineering Labs, U.S. Food and Drug Administration, Silver Spring, MD, USA.
| | - Ravi Samala
- Division of Imaging, Diagnostics, and Software Reliability, Office of Science and Engineering Labs, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Nicholas Petrick
- Division of Imaging, Diagnostics, and Software Reliability, Office of Science and Engineering Labs, U.S. Food and Drug Administration, Silver Spring, MD, USA
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Kaniuk E, Lechowska-Liszka A, Gajek M, Nikodem A, Ścisłowska-Czarnecka A, Rapacz-Kmita A, Stodolak-Zych E. Correlation between porosity and physicochemical and biological properties of electrospinning PLA/PVA membranes for skin regeneration. BIOMATERIALS ADVANCES 2023; 152:213506. [PMID: 37364396 DOI: 10.1016/j.bioadv.2023.213506] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/28/2023]
Abstract
Electrospinning is an increasingly popular technique for obtaining scaffolds for skin regeneration. However, electrospun scaffolds may also have some disadvantages, as the densely packed fibers in the scaffold structure can limit the penetration of skin cells into the inner part of the material. Such a dense arrangement of fibers can cause the cells to treat the 3D material as 2D one, and thus cause them to accumulate only on the upper surface. In this study, bi-polymer scaffolds made of polylactide (PLA) and polyvinyl alcohol (PVA) electrospun in a sequential or a concurrent system were investigated in a different PLA:PVA ratio (2:1 and 1:1). The properties of six types of model materials were investigated and compared i.e.; the initial materials electrospun by the sequential (PLA/PVA, 2PLA/PVA) and the concurrent system (PLA||PVA) and the same materials with removed PVA fibers (PLA/rPVA, 2PLA/rPVA, PLA||rPVA). The fiber models were intended to increase the porosity and coherent structure parameters of the scaffolds. The applied treatment involving the removal of PVA nanofibers increased the size of interfibrous pores formed between the PLA fibers. Ultimately, the porosity of the PLA/PVA scaffolds increased from 78 % to 99 %, and the time of water absorption decreased from 516 to 2 s. The change in wettability was induced by a synergistic effect of decrease in roughness after washing out and the presence of residual PVA fibers. The chemical analysis carried out confirmed the presence of PVA residues on the PLA fibers (FTIR-ATR study). In vitro studies were performed on human keratinocytes (HaKaT) and macrophages (RAW264.7), for which penetration into the inner part of the PLAIIPVA scaffold was observed. The new proposed approach, which allows the removal of PVA fibers from the bicomponent material, allows to obtain a scaffold with increased porosity, and thus better permeability for cells and nutrients.
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Affiliation(s)
- Ewa Kaniuk
- AGH University of Science and Technology, Al. Mickiewicza 30, Krakow, Poland
| | | | - Marcin Gajek
- AGH University of Science and Technology, Al. Mickiewicza 30, Krakow, Poland
| | - Anna Nikodem
- Wroclaw University of Science and Technology, 27 Wybrzeże Wyspiańskiego st., Wrocław, Poland
| | | | - Alicja Rapacz-Kmita
- AGH University of Science and Technology, Al. Mickiewicza 30, Krakow, Poland
| | - Ewa Stodolak-Zych
- AGH University of Science and Technology, Al. Mickiewicza 30, Krakow, Poland.
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Camparotto NG, Neves TDF, Mastelaro VR, Prediger P. Hydrophobization of aerogels based on chitosan, nanocellulose and tannic acid: Improvements on the aerogel features and the adsorption of contaminants in water. ENVIRONMENTAL RESEARCH 2023; 220:115197. [PMID: 36592805 DOI: 10.1016/j.envres.2022.115197] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/28/2022] [Accepted: 12/30/2022] [Indexed: 06/17/2023]
Abstract
Hydrophobic chitosan aerogels are promising adsorbents for immiscible contaminants such as oils and organic solvents. However, few studies have reported the application of hydrophobic aerogels as adsorbent for organic contaminants dissolved in water. Herein, novel highly hydrophobic chitosan (CS) beads containing cellulose nanocrystals (CNC) and hydrophobized tannic acid (HTA) composite were prepared with different CS and CNC-HTA content to achieve an optimized adsorbent to remove emerging contaminants from water in batch and fixed-bed assays. The CS@CNC-HTA beads properties were assessed by FTIR, XRD, SEM, XPS, Micro-CT, WCA, and zeta potential. Supramolecular interactions and physical interlacements between CS and CNC-HTA enabled the formation of CS@CNC-HTA beads with high porosity (98.6%), great volume of open pore space (10.16 mm3) and hydrophobicity (121.8°). The 1:1 CS@CNC-HTA beads showed the best performance for removing the pharmaceutical sildenafil citrate, the basic blue 26 dye, and the surfactant cetylpyridinium chloride, reaching adsorption capacities of 86 (73%), 375 (84%), and 390 (90%) mg.g-1, respectively. The 1:1 CS@CNC-HTA beads efficiently removed sildenafil citrate, basic blue 26 and cetylpyridinium chloride in fixed-bed experiments with exhaustion times of 890, 300, and 470 min, respectively. Theoretical calculations and adsorption assays indicate that the main attractive interactions are pyridinium-π, π-π, electrostatic and hydrophobic.
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Affiliation(s)
| | | | - Valmor Roberto Mastelaro
- São Carlos Institute of Physics, University of São Paulo - Usp, 13566-590, São Carlos, São Paulo, Brazil
| | - Patrícia Prediger
- School of Technology, University of Campinas - Unicamp, 13484-332, Limeira, São Paulo, Brazil.
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Investigation of the Interface between Laser-Melted CoCr and a Stainless Steel Substrate. METALS 2022. [DOI: 10.3390/met12060965] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recent advances in laser technologies offer significant flexibility in the additive manufacturing domain. Extensive work was focused on material processing using laser-directed energy deposition for repairing parts. This pilot study investigated the use of selective laser melting (SLM) for depositing a superior material such as CoCr on an existing stainless steel base. The interface between these dissimilar materials was analyzed. During fabrication, both metals were gradually mixed in the liquid state as the first CoCr powder layer was melded on the steel base without obvious defects. According to SEM and EDAX, the heat-affected zone has a limited depth (<20 µm). XRD patterns recorded across the CoCr–304 interface show a homogenous mixture of γ(Fe) and α(Co) solid solutions. The microporosity calculated by CT was under 0.5%. Microhardness was measured at and near the interface region, showing that the intermixing zone has high hardness (470–480 HV1), which may be related to the fine-grained microstructure. Mechanical testing reveals that the adhesion strength at rupture is 35% higher compared with the ultimate tensile strength of 304 steel. This adhesion strength can be attributed to the complete melting of CoCr particles after laser irradiation and to the reduced thickness of the HAZ and the IZ.
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Laser-based ultrasound interrogation of surface and sub-surface features in advanced manufacturing materials. Sci Rep 2022; 12:3309. [PMID: 35228598 PMCID: PMC8885670 DOI: 10.1038/s41598-022-07261-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 02/15/2022] [Indexed: 11/24/2022] Open
Abstract
Structures formed by advanced manufacturing methods increasingly require nondestructive characterization to enable efficient fabrication and to ensure performance targets are met. This is especially important for aerospace, military, and high precision applications. Surface acoustic waves (SAW) generated by laser-based ultrasound can detect surface and sub-surface defects relevant for a broad range of advanced manufacturing processes, including laser powder bed fusion (LPBF). In particular, an all-optical SAW generation and detection configuration can effectively interrogate laser melt lines. Here we report on scattered acoustic energy from melt lines, voids, and surface features. Sub-surface voids are also characterized using X-ray Computed Tomography (CT). High resolution CT results are presented and compared with SAW measurements. Finite difference simulations inform experimental measurements and analysis.
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Surface Finishing of Additive Manufactured Ti-6Al-4V Alloy: A Comparison between Abrasive Fluidized Bed and Laser Finishing. MATERIALS 2021; 14:ma14185366. [PMID: 34576590 PMCID: PMC8464882 DOI: 10.3390/ma14185366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 11/24/2022]
Abstract
Metal additive manufacturing is a major concern for advanced manufacturing industries thanks to its ability to manufacture complex-shaped parts in materials that are difficult to machine using conventional methods. Nowadays, it is increasingly being used in the industrial manufacturing of titanium-alloy components for aerospace and medical industries; however, the main weakness of structural parts is the fatigue life, which is affected by surface quality, meaning the micro-cracking of small surface defects induced by the manufacturing process. Laser finishing and Abrasive Fluidized Bed are proposed by the authors since they represent cost-effective and environment-friendly alternatives for automated surface finishing. A comparison between these two finishing technologies was established and discussed. Experimental tests investigated both mechanical properties and fatigue performances. The tests also focused on understanding the basic mechanisms involved in fatigue failures of machined Ti-6Al-4V components fabricated via Electron Beam Melting and the effects of operational parameters. X-ray tomography was used to evaluate the internal porosity to better explain the fatigue behaviour. The results demonstrated the capability of Laser finishing and Abrasive Fluidized Beds to improve failure performances. Life Cycle Analysis was additionally performed to verify the effectiveness of the proposed technologies in terms of environmental impact and resource consumption.
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Rajabi N, Rezaei A, Kharaziha M, Bakhsheshi-Rad HR, Luo H, RamaKrishna S, Berto F. Recent Advances on Bioprinted Gelatin Methacrylate-Based Hydrogels for Tissue Repair. Tissue Eng Part A 2021; 27:679-702. [PMID: 33499750 DOI: 10.1089/ten.tea.2020.0350] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Bioprinting of body tissues has gained great attention in recent years due to its unique advantages, including the creation of complex geometries and printing the patient-specific tissues with various drug and cell types. The most momentous part of the bioprinting process is bioink, defined as a mixture of living cells and biomaterials (especially hydrogels). Among different biomaterials, natural polymers are the best choices for hydrogel-based bioinks due to their intrinsic biocompatibility and minimal inflammatory response in body condition. Gelatin methacryloyl (GelMA) hydrogel is one of the high-potential hydrogel-based bioinks due to its easy synthesis with low cost, great biocompatibility, transparent structure that is useful for cell monitoring, photocrosslinkability, and cell viability. Furthermore, the potential of adjusting properties of GelMA due to the synthesis protocol makes it a suitable choice for soft or hard tissues. In this review, different methods for the bioprinting of GelMA-based bioinks, as well as various effective process parameters, are reviewed. Also, several solutions for challenges in the printing of GelMA-based bioinks are discussed, and applications of GelMA-based bioprinted tissues argued as well. Impact statement Bioprinting has been demonstrated as a promising and alternative approach for organ transplantation to develop various types of living tissue. Bioinks, with great biological characteristics similar to the host tissues and rheological/flow features, are the first requirements for the successful bioprinting approach. Gelatin methacryloyl (GelMA) hydrogel is one of the high-potential hydrogel-based bioinks. This review provides a comprehensive look at different methods for the bioprinting of GelMA-based bioinks and applications of GelMA-based bioprinted tissues for tissue repair.
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Affiliation(s)
- Negar Rajabi
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran
| | - Ali Rezaei
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran
| | - Mahshid Kharaziha
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran
| | - Hamid Reza Bakhsheshi-Rad
- Advanced Materials Research Center, Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
| | - Hongrong Luo
- National Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Seeram RamaKrishna
- Department of Mechanical Engineering, National University of Singapore, Singapore
| | - Filippo Berto
- Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, Trondheim, Norway
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Sagandira CR, Siyawamwaya M, Watts P. 3D printing and continuous flow chemistry technology to advance pharmaceutical manufacturing in developing countries. ARAB J CHEM 2020; 13:7886-7908. [PMID: 34909056 PMCID: PMC7511217 DOI: 10.1016/j.arabjc.2020.09.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/12/2020] [Accepted: 09/13/2020] [Indexed: 12/18/2022] Open
Abstract
The realization of a downward spiralling of diseases in developing countries requires them to become self-sufficient in pharmaceutical products. One of the ways to meet this need is by boosting the local production of active pharmaceutical ingredients and embracing enabling technologies. Both 3D printing and continuous flow chemistry are being exploited rapidly and they are opening huge avenues of possibilities in the chemical and pharmaceutical industries due to their well-documented benefits. The main barrier to entry for the continuous flow chemistry technique in low-income settings is the cost of set-up and maintenance through purchasing of spare flow reactors. This review article discusses the technical considerations for the convergence of state-of-the-art technologies, 3D printing and continuous flow chemistry for pharmaceutical manufacturing applications in developing countries. An overview of the 3D printing technique and its application in fabrication of continuous flow components and systems is provided. Finally, quality considerations for satisfying regulatory requirements for the approval of 3D printed equipment are underscored. An in-depth understanding of the interrelated aspects in the implementation of these technologies is crucial for the realization of sustainable, good quality chemical reactionware.
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Affiliation(s)
| | | | - Paul Watts
- Nelson Mandela University, University Way, Port Elizabeth 6031, South Africa,Corresponding author
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Use of X-ray Computed Tomography for Assessing Defects in Ti Grade 5 Parts Produced by Laser Melting Deposition. METALS 2020. [DOI: 10.3390/met10111408] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Laser Melting Deposition (LMD) is a metal printing technique that allows for the manufacturing of large objects by Directed Energy Deposition. Due to its versatility in variation of parameters, the possibility to use two or more materials, to create alloys in situ or produce multi-layer structures, LMD is still being scientifically researched and is still far from industrial maturity. The structural testing of obtained samples can be time consuming and solutions that can decrease the samples analysis time are constantly proposed in the scientific literature. In this manuscript we present a quality improvement study for obtaining defect-free bulk samples of Ti6Al4V under X-Ray Computed Tomography (XCT) by varying the hatch spacing and distance between planes. Based on information provided by XCT, the experimental conditions were changed until complete elimination of porosity. Information on the defects in the bulk of the samples by XCT was used for feedback during parameters tuning in view of complete removal of pores. The research time was reduced to days instead of weeks or months of samples preparation and analysis by destructive metallographic techniques.
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DU Plessis A. X-ray tomography for the advancement of laser powder bed fusion additive manufacturing. J Microsc 2020; 285:121-130. [PMID: 32496595 DOI: 10.1111/jmi.12930] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/22/2020] [Accepted: 05/29/2020] [Indexed: 01/03/2023]
Abstract
X-ray computed tomography is a powerful tool to nondestructively inspect additively manufactured parts. Additive manufacturing of metals, especially laser powder bed fusion, is increasingly being adopted for serial production of critical components in aerospace, automotive and various other industries. The technology holds huge potential for more efficient material usage and light weighting of components, among the many advantages. As this new production method is being ramped up and refined in various industry sectors, X-ray tomography is critical to the advancement of the quality of the produced components. X-ray tomography allows the nondestructive evaluation of the structural integrity of the parts produced, which in turn provides confidence in the expected performance of the parts. Besides final inspection of parts for porosity/defects and dimensional tolerances for a pass/fail decision, X-ray tomography also has a critical role to play in advancing and improving the additive manufacturing processes. This process improvement refers to the inspection of small representative coupon samples on a microscopic scale, in order to optimize the process parameters such as laser power, speed, scan strategy and various others. In this work, we describe the evaluation of small solid cube coupon samples and lattice structure coupon samples. These examples are meant to improve the understanding of the potential of X-ray tomography in advancing additive manufacturing processes (in contrast to its usual use for nondestructive testing of final parts), thereby providing support towards qualification of these processes and the parts produced in these processes. X-ray tomography, therefore, plays a key role in the adoption and qualification of high-quality metal additive manufacturing.
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Affiliation(s)
- A DU Plessis
- Research group 3DInnovation, Stellenbosch University, Stellenbosch, South Africa.,Department of Mechanical Engineering, Nelson Mandela University, Port Elizabeth, South Africa
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du Plessis A, Sperling P, Beerlink A, du Preez WB, le Roux SG. Standard method for microCT-based additive manufacturing quality control 4: Metal powder analysis. MethodsX 2018; 5:1336-1345. [PMID: 30406023 PMCID: PMC6215023 DOI: 10.1016/j.mex.2018.10.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 10/11/2018] [Indexed: 10/31/2022] Open
Abstract
X-ray micro computed tomography (microCT) can be applied to analyse powder feedstock used in additive manufacturing. In this paper, we demonstrate a dedicated workflow for this analysis method, specifically for Ti6Al4V powder typically used in commercial powder bed fusion (PBF) additive manufacturing (AM) systems. The methodology presented includes sample size requirements, scan conditions and settings, reconstruction and image analysis procedures. We envisage this method will support standardization in powder analysis in the additive manufacturing community. This is aimed at ultimately improving the quality of additively manufactured parts, through the identification of impurities and defects in powders. •MicroCT analysis of metal powders for additive manufacturing•Method describes a standard workflow simplifying usage of the technique•Sample requirements and image analysis workflow is described.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
| | | | | | - Willie B du Preez
- Dept of Mechanical Engineering Dept, Central University of Technology, Free State, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
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du Plessis A, Sperling P, Beerlink A, Tshabalala L, Hoosain S, Mathe N, le Roux SG. Standard method for microCT-based additive manufacturing quality control 2: Density measurement. MethodsX 2018; 5:1117-1123. [PMID: 30294559 PMCID: PMC6168933 DOI: 10.1016/j.mex.2018.09.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/11/2018] [Indexed: 11/25/2022] Open
Abstract
MicroCT is best known for its ability to detect and quantify porosity or defects, and to visualize its 3D distribution. However, it is also possible to obtain accurate volumetric measurements from parts – this can be used in combination with the part mass to provide a good measure of its average density. The advantage of this density-measurement method is the ability to combine the density measurement with visualization and other microCT analyses of the same sample. These other analyses may include detailed porosity or void analysis (size and distribution) and roughness assessment, obtainable with the same scan data. Simple imaging of the interior of the sample allows the detection of unconsolidated powder, open porosity to the surface or the presence of inclusions. The CT density method presented here makes use of a 10 mm cube sample and a simple data analysis workflow, facilitating standardization of the method. A laboratory microCT scanner is required at 15 μm voxel size, suitable software to allow sub-voxel precise edge determination of the scanned sample and hence an accurate total volume measurement, and a scale with accuracy to 3 digits. MicroCT-based mean density measurement method. Accurate volume measurement and scale mass. 10 mm cube sample allows standardization and automation of workflow.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
| | | | | | - Lerato Tshabalala
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Shaik Hoosain
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Ntombi Mathe
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
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Standard method for microCT-based additive manufacturing quality control 3: Surface roughness. MethodsX 2018; 5:1111-1116. [PMID: 30294558 PMCID: PMC6168927 DOI: 10.1016/j.mex.2018.09.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/11/2018] [Indexed: 12/30/2022] Open
Abstract
The use of microCT of 10 mm coupon samples produced by AM has the potential to provide useful information of mean density and detailed porosity information of the interior of the samples. In addition, the same scan data can be used to provide surface roughness analysis of the as-built surfaces of the same coupon samples. This can be used to compare process parameters or new materials. While surface roughness is traditionally done using tactile probes or with non-contact interferometric techniques, the complex surfaces in AM are sometimes difficult to access and may be very rough, with undercuts and may be difficult to accurately measure using traditional techniques which are meant for smoother surfaces. This standard workflow demonstrates on a coupon sample how to acquire surface roughness results, and compares the results from roughly the same area of the same sample with tactile probe results. The same principle can be applied to more complex parts, keeping in mind the resolution limit vs sample size of microCT.
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