Comparison of Different Parameters to Evaluate Delamination in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP)

[EN] Delamination is one of the main problems that occur when machining fiber-reinforced composite materials. In this work, Types I and II of delamination are studied separately in edge trimming of basalt fiber reinforced plastic (BFRP). For this purpose, one-dimensional and area delamination parameters are defined. One-dimensional parameters (Wa and Wb) allow to know average fibers length while the analysis of area delamination parameters (Sd) allow to evaluate delamination density. To study delamination, different tests are carried out modifying cutting parameters (cutting speed, feed per tooth and depth of cut) and material characteristics (fiber volume fraction and fiber orientation). Laminates with a lower fiber volume fraction do not present delamination. Attending to one-dimensional parameters it can be concluded that Type II delamination is more important than Type I and that a high depth of cut generates higher values of delamination parameters. An analysis of variance (ANOVA) is performed to study area parameters. Although delamination has a random nature, for each depth of cut, more influence variables in area delamination are firstly, feed per tooth and secondly, cutting speed.This research was funded by Government of Spain, grant number PID2019-108807RB-I00.Navarro-Mas, M.; Meseguer, M.; Lluch-Cerezo, J.; García Manrique, JA. (2020). Comparison of Different Parameters to Evaluate Delamination in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP). Materials. 13(23):1-17. https://doi.org/10.3390/ma13235326S1171323Lopresto, V., Caggiano, A., & Teti, R. (2016). High Performance Cutting of Fibre Reinforced Plastic Composite Materials. Procedia CIRP, 46, 71-82. doi:10.1016/j.procir.2016.05.079Ozkan, D., Panjan, P., Gok, M. S., & Karaoglanli, A. C. (2020). Experimental Study on Tool Wear and Delamination in Milling CFRPs with TiAlN- and TiN-Coated Tools. Coatings, 10(7), 623. doi:10.3390/coatings10070623Nguyen-Dinh, N., Bouvet, C., & Zitoune, R. (2019). Influence of machining damage generated during trimming of CFRP composite on the compressive strength. Journal of Composite Materials, 54(11), 1413-1430. doi:10.1177/0021998319883335Razfar, M. R., & Zadeh, M. R. Z. (2009). Optimum damage and surface roughness prediction in end milling glass fibre-reinforced plastics, using neural network and genetic algorithm. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 223(6), 653-664. doi:10.1243/09544054jem1409Neeli, N., Jenarthanan, M. P., & Dileep Kumar, G. (2018). Multi-response optimization for machining GFRP composites using GRA and DFA. Multidiscipline Modeling in Materials and Structures, 14(3), 482-496. doi:10.1108/mmms-08-2017-0092Azmi, A. I., Lin, R. J. T., & Bhattacharyya, D. (2012). Machinability study of glass fibre-reinforced polymer composites during end milling. The International Journal of Advanced Manufacturing Technology, 64(1-4), 247-261. doi:10.1007/s00170-012-4006-6Jenarthanan, M. P., & Jeyapaul, R. (2018). Optimisation of machining parameters on milling of GFRP composites by desirability function analysis using Taguchi method. International Journal of Engineering, Science and Technology, 5(4), 22-36. doi:10.4314/ijest.v5i4.3Sreenivasulu, R. (2013). Optimization of Surface Roughness and Delamination Damage of GFRP Composite Material in End Milling Using Taguchi Design Method and Artificial Neural Network. Procedia Engineering, 64, 785-794. doi:10.1016/j.proeng.2013.09.154He, Y., Qing, H., Zhang, S., Wang, D., & Zhu, S. (2017). The cutting force and defect analysis in milling of carbon fiber-reinforced polymer (CFRP) composite. The International Journal of Advanced Manufacturing Technology, 93(5-8), 1829-1842. doi:10.1007/s00170-017-0613-6Raj, P. P., & Perumal, A. E. (2010). Taguchi Analysis of surface roughness and delamination associated with various cemented carbide K10 end mills in milling of GFRP. Journal of Engineering Science and Technology Review, 3(1), 58-64. doi:10.25103/jestr.031.11Hintze, W., Hartmann, D., & Schütte, C. (2011). Occurrence and propagation of delamination during the machining of carbon fibre reinforced plastics (CFRPs) – An experimental study. Composites Science and Technology, 71(15), 1719-1726. doi:10.1016/j.compscitech.2011.08.002Wang, F., Yin, J., Ma, J., Jia, Z., Yang, F., & Niu, B. (2017). Effects of cutting edge radius and fiber cutting angle on the cutting-induced surface damage in machining of unidirectional CFRP composite laminates. The International Journal of Advanced Manufacturing Technology, 91(9-12), 3107-3120. doi:10.1007/s00170-017-0023-9Li, M., Huang, M., Jiang, X., Kuo, C., & Yang, X. (2018). Study on burr occurrence and surface integrity during slot milling of multidirectional and plain woven CFRPs. The International Journal of Advanced Manufacturing Technology, 97(1-4), 163-173. doi:10.1007/s00170-018-1937-6Sheikh-Ahmad, J. Y., Dhuttargaon, M., & Cheraghi, H. (2017). New tool life criterion for delamination free milling of CFRP. The International Journal of Advanced Manufacturing Technology, 92(5-8), 2131-2143. doi:10.1007/s00170-017-0240-2Szwajka, K., & Trzepieciński, T. (2016). Effect of tool material on tool wear and delamination during machining of particleboard. Journal of Wood Science, 62(4), 305-315. doi:10.1007/s10086-016-1555-6Wang, F., Zhang, B., Jia, Z., Zhao, X., & Wang, Q. (2019). Structural optimization method of multitooth cutter for surface damages suppression in edge trimming of Carbon Fiber Reinforced Plastics. Journal of Manufacturing Processes, 46, 204-213. doi:10.1016/j.jmapro.2019.09.013Masek, P., Zeman, P., Kolar, P., & Holesovsky, F. (2018). Edge trimming of C/PPS plates. The International Journal of Advanced Manufacturing Technology, 101(1-4), 157-170. doi:10.1007/s00170-018-2857-1Dhand, V., Mittal, G., Rhee, K. Y., Park, S.-J., & Hui, D. (2015). A short review on basalt fiber reinforced polymer composites. Composites Part B: Engineering, 73, 166-180. doi:10.1016/j.compositesb.2014.12.011Navarro-Mas, M., García-Manrique, J., Meseguer, M., Ordeig, I., & Sánchez, A. (2018). Delamination Study in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP). Materials, 11(8), 1418. doi:10.3390/ma1108141

Stochastic inverse finite element modeling for characterization of heterogeneous material properties

[EN] The micro and meso-structural characteristics of materials present an inherent variability because of the intrinsic scatter in raw material and manufacturing processes. This problem is exacerbated in highly heterogeneous materials, which shows significant uncertainties in the macroscale material properties. Therefore, providing optimal designs and reliable structural analyses strongly depend on the selection of the underlying material property models. This paper is intended to provide insight into such a dependence by means of a stochastic inverse model based on an iterative optimization process depending only of one parameter, thus avoiding complex parametrizations. It relies on nonlinear combinations of material property realizations with a defined spatial structure for constraining stochastic simulations to data within the framework of a Finite Element approach. In this way, the procedure gradually deforms unconditional material property realizations to approximate the reproduction of information including mechanical parameters (such as Young's modulus and Poisson's ratio fields) and variables (e.g., stress and strain fields). It allows dealing with non-multiGaussian structures for the spatial structure of the material property realizations, thus allowing to reproduce the coalescence and connectivity among phases and existing crack patterns that often take place in composite materials, being these features crucial in order to obtain more reliable safety factors and fatigue life predictions. The methodology has been successfully applied for the characterization of a complex case study, where an uncertainty assessment has been carried out by means of multiple equally likely realizations.Llopis-Albert, C.; Rubio Montoya, FJ.; Valero Chuliá, FJ.; Liao, H.; Zeng, S. (2019). Stochastic inverse finite element modeling for characterization of heterogeneous material properties. Materials Research Express. 6(11):1-16. https://doi.org/10.1088/2053-1591/ab4c72S116611Albanesi, A., Bre, F., Fachinotti, V., & Gebhardt, C. (2018). Simultaneous ply-order, ply-number and ply-drop optimization of laminate wind turbine blades using the inverse finite element method. Composite Structures, 184, 894-903. doi:10.1016/j.compstruct.2017.10.051Albanesi, A., Fachinotti, V., Peralta, I., Storti, B., & Gebhardt, C. (2017). Application of the inverse finite element method to design wind turbine blades. Composite Structures, 161, 160-172. doi:10.1016/j.compstruct.2016.11.039Borkowski, L., & Kumar, R. S. (2018). Inverse method for estimation of composite kink-band toughness from open-hole compression strength data. Composite Structures, 186, 183-192. doi:10.1016/j.compstruct.2017.12.006Baby, A., Nayak, S. Y., Heckadka, S. S., Purohit, S., Bhagat, K. K., & Thomas, L. G. (2019). 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Identification of Mechanical Material Behavior Through Inverse Modeling and DIC. Experimental Mechanics, 48(4), 421-433. doi:10.1007/s11340-007-9094-0Goodarzi, A., Fotouhi, M., & Shodja, H. M. (2016). Inverse scattering problem of reconstruction of an embedded micro-/nano-size scatterer within couple stress theory with micro inertia. Mechanics of Materials, 103, 123-134. doi:10.1016/j.mechmat.2016.09.011Herrera-Solaz, V., Segurado, J., & LLorca, J. (2015). On the robustness of an inverse optimization approach based on the Levenberg–Marquardt method for the mechanical behavior of polycrystals. European Journal of Mechanics - A/Solids, 53, 220-228. doi:10.1016/j.euromechsol.2015.05.005Hu, L. Y. (2000). Mathematical Geology, 32(1), 87-108. doi:10.1023/a:1007506918588Ignacio, I. (2014). Different Ways to Consider Heterogeneity in Quase-fragile Materials Using a Version of Lattice Model. Procedia Materials Science, 3, 499-504. doi:10.1016/j.mspro.2014.06.083Kashfi, M., Majzoobi, G. 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Mechanical Systems and Signal Processing, 27, 471-483. doi:10.1016/j.ymssp.2011.09.004Mikdam, A., Makradi, A., Koutsawa, Y., & Belouettar, S. (2013). Microstructure effect on the mechanical properties of heterogeneous composite materials. Composites Part B: Engineering, 44(1), 714-721. doi:10.1016/j.compositesb.2012.01.081Mortazavi, F., Ghossein, E., Lévesque, M., & Villemure, I. (2014). High resolution measurement of internal full-field displacements and strains using global spectral digital volume correlation. Optics and Lasers in Engineering, 55, 44-52. doi:10.1016/j.optlaseng.2013.10.007Ni, Y., & Chiang, M. Y. M. (2007). Prediction of elastic properties of heterogeneous materials with complex microstructures. Journal of the Mechanics and Physics of Solids, 55(3), 517-532. doi:10.1016/j.jmps.2006.09.001Pitangueira, R. L., & Silva, R. R. e. (2002). Numerical Characterization of Concrete Heterogeneity. 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Design and simulation of a resorbable bone fixation plate made by additive manufacturing for femoral mid-SHAFT fractures

[EN] Finite element method has been employed to establish the feasibility of a fixation plate made of PLA by additive manufacturing for femoral shaft fractures. For this purpose, Von Mises stress and the pressure contact between bones had been analysed. The proposed design has been compared with an actual titanium fixation plate as a point of reference.J. Ivorra-Martinez is funded with a Formación de Profesorado Universitario (FPU) grant from the Spanish Government (Ministerio de Ciencia, Innovación y Universidades), with reference FPU19/01759.Ivorra Martínez, J.; Sellés Cantó, MÁ.; Sánchez Caballero, S.; Boronat Vitoria, T. (2021). Design and simulation of a resorbable bone fixation plate made by additive manufacturing for femoral mid-SHAFT fractures. Journal of Applied Research in Technology & Engineering. 2(1):11-16. https://doi.org/10.4995/jarte.2021.14712OJS111621Alizadeh-Osgouei, M., Li, Y., Wen, C. (2019). 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Mechanical properties of components fabricated with open-source 3-D printers under realistic environmental conditions. Materials & Design, 58, 242-246. https://doi.org/10.1016/j.matdes.2014.02.038Wang, A.Y., Peng, J., Sun, M.X., Sui, X., Wang, X., Tian, Y., Lu, S.B. (2006). Biomechanical comparison of different structural bone grafting in femoral heads' defects of weight-bearing region. Journal of Medical Biomechanics, 4.Wang, J., Ma, J.X., Lu, B., Bai, H.H., Wang, Y., Ma, X.L. (2020). Comparative finite element analysis of three implants fixing stable and unstable subtrochanteric femoral fractures: Proximal Femoral Nail Antirotation (PFNA), Proximal Femoral Locking Plate (PFLP), and Reverse Less Invasive Stabilization System (LISS). Orthopaedics & Traumatology: Surgery & Research, 106(1), 95-101. https://doi.org/10.1016/j.otsr.2019.04.027Wang, X., Xu, S., Zhou, S., Xu, W., Leary, M., Choong, P., Xie, Y.M. (2016). 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Geometric Modeling of Cellular Materials for Additive Manufacturing in Biomedical Field: A Review

Advances in additive manufacturing technologies facilitate the fabrication of cellular materials that have tailored functional characteristics. The application of solid freeform fabrication techniques is especially exploited in designing scaffolds for tissue engineering. In this review, firstly, a classification of cellular materials from a geometric point of view is proposed; then, the main approaches on geometric modeling of cellular materials are discussed. Finally, an investigation on porous scaffolds fabricated by additive manufacturing technologies is pointed out. Perspectives in geometric modeling of scaffolds for tissue engineering are also proposed

Composite foundations on Malaysian soft clay soil: applications of innovative techniques

An innovative technique of electro osmosis coupled with vertical surcharge loading to accelerate the consolidation and stiffen Kaolin (China Clay Grade E) was investigated in this study. The geotechnical properties of this China Clay Kaolin Grade E and the design of electro osmotic consolidation chamber are discussed together with an explanation of the procedural concept of the electro osmotic consolidation chamber (i.e., the preparation of the apparatus and the clay sample, assembling of the electro osmotic consolidation chamber; and the experimental work). The plastic limit, liquid limit and plasticity index were 35%, 53% and 18% respectively. Therefore, China Clay Kaolin Grade E is classified as MH soil, and it is predominantly a silt with high plasticity. The specific gravity of the soil is 2.65. To ensure the kaolin is saturated, all samples were prepared in a similar manner with deaired water to produce a slurry at 150% of the liquid limit (initial moisture content of 79.5%). The electro osmotic consolidation chamber was cylindrical and consisted of the body, the base and the top cap. The body and the base of the chamber were constructed of polyvinyl chloride (PVC) tube with a wall thickness of 10.9 mm, 345 mm high and 251 mm inner diameter. The electro osmotic consolidation chamber was assembled together with a 45 mm thick flange and collar. The top cap of this chamber was based on that of a Rowe cell of similar diameter. Twenty one tests were performed in this study with an applied voltage and one test was a control test. The test samples in the twenty one tests were all consolidated to three different phases. In Phases 1 and 2, the samples were consolidated at 15 kPa while in the Phase 3, 50 kPa was used. The electro osmotic process was only performed during Phase 2. The time of treatment, numbers of electrodes, the arrangement of electrodes, and the applied voltages were investigated in these tests. Results from these tests indicated that the China Clay Kaolin Grade E in a 79.5% slurry form responded well to electro osmotic treatment and that electro osmotic process increased the overall stiffness of the soil as indicated by the reduced relative settlement in Phase 3 with a pressure of 50kPa. The water content around the anodes was less than that at the cathode creating zones of higher average constrained stiffness. The tests demonstrated that the longer the time of treatment, the greater the numbers of anodes, the shorter distance between the electrodes and the higher the applied voltages associated with electro osmosis increased the average stiffness of the soil mass confirming the concept of an electro osmotic pile. Keywords: electro osmotic merged vertical loading and electro osmotic, consolidation, electro osmotic consolidation chamber, stiffening

Extruded and injection moulded virgin PA 6/6 as abrasion resistant material

Polyamide (PA6/6) is often used as a tribological pair in abrasion prevalent applications such as hinges and sliders. PA6/6 is frequently processed by injection moulding and extrusion process. It is known that these processes influence the polymers mechanical behaviour, but their influence on the polymers wear response has not been studied. Hence the present research attempts to study the influence of different manufacturing processes on tribological behaviour for PA6/6. Wear tests were performed on a pin abrading tester (DIN 50322). Abrasion resistance of both extruded and injection moulded PA6/6 were tested at different loads (20 and 35 N). Single-pass (nonoverlapping mode) and multipass testing (overlapping mode) were used to understand the influence of clogging of wear debris. It is evidenced that with increasing load the specific wear rate decreases; moreover, fine abrasives tend to reduce the wear rate. In multipass testing a transfer layer clogged on the counterface that acted as a protective agent and lowers wear rate. Poor mechanical strength of injection moulded polymers is apparently compensated by microstructural response for having a similar wear behaviour between extruded and injection moulded PA 6/6. Hence a proper balance between microstructural and mechanical characteristics is an absolute must in PA 6/6 for better wear performance

A review of metal foam and metal matrix composites for heat exchangers and heat Sinks

Recent advances in manufacturing methods open the possibility for broader use of metal foams and metal matrix composites (MMCs) for heat exchangers, and these materials can have tailored material properties. Metal foams in particular combine a number of interesting properties from a heat exchanger's point of view. In this paper, the material properties of metal foams and MMCs are surveyed, and the current state of the art is reviewed for heat exchanger applications. Four different applications are considered: liquid-liquid, liquid-gas, and gas-gas heat exchangers and heat sinks. Manufacturing and implementation issues are identified and discussed, and it is concluded that these materials hold promise both for heat exchangers and heat sinks, but that some key issues still need to be solved before broad-scale application is possible

Compression properties of polymeric syntactic foam composites under cyclic loading

Syntactic foams are composite materials frequently used in applications requiring the properties of low density and high damage tolerance. In the present work, polymer-based syntactic foams were studied under cyclic compression in order to investigate their compressibility, recoverability, energy dissipation and damage tolerance. These syntactic foams were manufactured by adding hollow polymer microspheres of various sizes and wall thicknesses into a polyurethane matrix. The associated loading and unloading curves during cyclic testing were recorded, revealing the viscoelastic nature of the materials. SEM images of the samples were obtained in order to study potential damage mechanisms during compression. It was observed that these syntactic foams exhibit high elastic recovery and energy dissipation over a wide range of compressional strains and the addition of polymer microspheres mitigate the damage under compressional loading.Comment: 25 pages, 13 figure

Thermophysical Phenomena in Metal Additive Manufacturing by Selective Laser Melting: Fundamentals, Modeling, Simulation and Experimentation

Among the many additive manufacturing (AM) processes for metallic materials, selective laser melting (SLM) is arguably the most versatile in terms of its potential to realize complex geometries along with tailored microstructure. However, the complexity of the SLM process, and the need for predictive relation of powder and process parameters to the part properties, demands further development of computational and experimental methods. This review addresses the fundamental physical phenomena of SLM, with a special emphasis on the associated thermal behavior. Simulation and experimental methods are discussed according to three primary categories. First, macroscopic approaches aim to answer questions at the component level and consider for example the determination of residual stresses or dimensional distortion effects prevalent in SLM. Second, mesoscopic approaches focus on the detection of defects such as excessive surface roughness, residual porosity or inclusions that occur at the mesoscopic length scale of individual powder particles. Third, microscopic approaches investigate the metallurgical microstructure evolution resulting from the high temperature gradients and extreme heating and cooling rates induced by the SLM process. Consideration of physical phenomena on all of these three length scales is mandatory to establish the understanding needed to realize high part quality in many applications, and to fully exploit the potential of SLM and related metal AM processes