Complex Composite Materials Research Articles

Advancements in Biofiller-Reinforced PLA Composites for 3D Printing: A Review

Additive manufacturing is key in realizing highly complex and high-performance composite materials. Among all the various kinds of functionality that could be added to a composite component, continuous fiber-reinforced composites have been drawing much attention because of their attractive combination of properties. The comprehensive spectrum of knowledge that ranges from the basics concerned with structure, morphology, synthesis, physical, and chemical properties finally reaches to this analytical study of advanced composites. Most generally, such a composite is structured on a thermoplastic or thermoset polymer matrix that embeds the load-carrying reinforcing fibers; probably best known are carbon, glass, and aramid fibers. These composites, which involve fibers continuously reinforcing, have high strength relative to their weight. They are also anisotropic, meaning they have qualities that vary from one direction to another – something which might be customisable for specific load cases. They warp and shrink less during their life in an outside environment than conventionally made bioplastics due to a fact that short fibers can provide reinforcement to them. This 3-D printing object is manufactured by special additive manufacture technology during the manufacturing process after compounding and extruding the fiber-reinforced composite filament. The final properties of 3D printed parts could be tailorable through changing variables such a fiber type, fiber length, volume fraction, polymer matrix material, orientation of fibers, and printing process parameters. These continuous fiber-reinforced 3D printed composites could achieve tensile strengths up to one GPa, have stiffness values reaching even a rating of countless Gpa, and have ad thicknesses in the range from about 1.4–1.8 g/cm³. This finding could be applied in basically all major industries, from aerospace and the automotive industry to sports gear. Such conclusions from the analysis may be useful in the selection of appropriate materials and techniques while even guiding the development of new applications with respect to such advanced composite materials.

Changes in the biological and nutritional value of pea and bean grains as a result of their bioactivation

The relevance of the study is due to the need to improve the technology for processing peas and beans of domestic selection into plant-based drinks and their use in technologies for alternative products of complex raw materials for healthy, functional and specialized nutrition of various population groups. The purpose of the work is to study the influence of the developed technological modes of bioactivation on the nutritional and biological value, functional and technological properties of the protein-carbohydrate complex of pea and bean grains. The work examines the results of studies of changes occurring in pea grains bred at the Bashkir Research Institute of Agriculture and beans bred at the Omsk State Agrarian University during their bioactivation using the Smart Sprouter "Rosinka" installation, in particular the biochemical composition and inhibitory activity of grain of the studied varieties, a protein complex and amino acid composition, protein digestibility in vitro, functional and technological properties of the protein-carbohydrate complex of grain. The research has been carried out using generally accepted, modern instrumental methods for analyzing the properties of raw materials and finished products. It has been established that the use of the developed technological parameters of bioactivation leads to modification of the functional and technological properties of the structure-forming nutrients of grain, intensive accumulation of all amino acids, with the exception of threonine, make it possible to increase the protein content in pea grain by 15.32 % and beans by 14.96 %, relative to the initial values increase the degree of compliance of pea and bean grain protein with the FAO/WHO reference protein by 4.48 and 17.53 %, reduce the activity of grain protease inhibitors by 19.76 and 26.12 %, increase the digestibility of grain protein by 7.77 and 5.85 %. The research results prove the feasibility of using bioactivated pea and bean grains for the production of alternative products with a complex raw material composition, including plant-based drinks and products in the "dairy alternatives" segment.

Influence of Gamma-Phase Aluminum Oxide Nanopowder and Polyester-Glass Recyclate Filler on the Destruction Process of Composite Materials Reinforced by Glass Fiber.

Recycling of composite materials is an important global issue due to the wide use of these materials in many industries. Waste management options are being explored. Mechanical recycling is one of the methods that allows obtaining polyester-glass recyclate in powder form as a result of appropriate crushing and grinding of waste. Due to the fact that the properties of composites can be easily modified by adding various types of fillers and nanofillers, this is one of the ways to improve the properties of such complex composite materials. This article presents the strength parameters of composites with the addition of fillers in the form of polyester-glass recyclate and a nanofiller in the form of gamma-phase aluminum nanopowder. To analyze the obtained results, Kolmogorov-Sinai (K-S) metric entropy was used to determine the transition from the elastic to the viscoelastic state in materials without and with the addition of nanoaluminum, during a static tensile test. The tests included samples with the addition of fillers and nanofillers, as well as a base sample without any additives. The article presents the strength parameters obtained from a testing machine during a static tensile test. Additionally, the acoustic emission method was used during the research. Thanks to which, graphs of the effective value of the electrical signal (RMS) were prepared as a function of time, the parameters were previously identified as extremely useful for analyzing the destruction process of composite materials. The values obtained from the K-S metric entropy method and the acoustic emission method were plotted on sample stretching graphs. The influence of the nanofiller and filler on these parameters was also analyzed. The presented results showed that the aluminum nanoadditive did not increase the strength parameters of the composite with recyclate as a result of the addition of aluminum nanofiller; however, its addition influenced the operational parameters, which is reflected in a 5% increase in the UTS value (from 55% to 60%).

Correlated 4D-STEM and EDS for the classification of fine Beta-precipitates in aluminum alloy AA 6063-T6

Tuning the properties of aluminum alloys AA 6063-T6 involves artificial aging to induce precipitate formation, particularly β’’ and β’ phases. Previous characterization challenges due to their similar appearance are addressed here by correlating 4D scanning transmission electron microscopy (4DSTEM) and energy-dispersive spectroscopy (EDS) mapping. This approach allows us to analyze the structure and composition of precipitates individually, overcoming limitations of conventional imaging and structural analysis techniques when the precipitates appear simultaneously, as is often the case. We present detailed characterizations of needle-shaped Beta precipitates, revealing distinct diffraction patterns (DPs) and compositional differences. The method's applicability extends beyond aluminum alloys, offering a promising strategy for complex composite material characterization with multimodal scanning transmission electron microscopy (STEM) techniques.

Multiscale damage and low-velocity impact study of three-dimensional woven composites

Three-dimensional woven composites address the limitation of weak interlaminar strength found in traditional laminated composites and offer superior resistance to out-of-plane impact. However, the complex material composition and structural intricacies necessitate investigation into their damage mechanisms. This study introduces novel and reliable microscale and mesoscale Representative Volume Element (RVE) models for three-dimensional woven composites, developed through advanced CT scanning and comprehensive multi-directional tensile and shear experiments. The research explores the impact of fiber volume fraction on yarn mechanical properties using the microscale RVE model, yielding precise macroscale homogenization parameters through the mesoscale RVE model. Furthermore, a macro-meso model tailored for low-velocity impact scenarios is established, significantly enhancing computational efficiency without compromising accuracy, thus providing support for further research on the impact properties of three-dimensional woven composites.

Decoding thermal properties in polymer-inorganic heat dissipators: a data-driven approach using pyrolysis mass spectrometry

ABSTRACT Polymeric materials can boost their performances by strategically incorporating inorganic substances. Heat dissipators are a representative class of such composite materials, where inorganic fillers and matrix polymers contribute to high thermal conductivity and strong adhesion, respectively, resulting in excellent heat dissipation performance. However, due to the complex interaction between fillers and polymers, even slight differences in structural parameters, e.g. dispersion/aggregation degree of fillers and crosslink density of polymers, may significantly impact material performance, complicating the quality management and guidelines for material developments. Therefore, we introduce pyrolysis mass spectra (MS) as material descriptors. On the basis of these spectra, we construct prediction models using a data-driven approach, specifically focusing on thermal conductivity and adhesion, which are key indicators for heat dissipating performance. Pyrolysis-MS observes thermally decomposable polymers, which occupy only 0.1 volume fraction of the heat dissipators; nevertheless, the physical states of non-decomposable inorganic fillers are implicitly reflected in the pyrolyzed fragment patterns of the matrix polymers. Consequently, pyrolysis-MS provides sufficient information to construct accurate models for predicting heat dissipation performance, simplifying quality management by substituting time-consuming performance evaluations with rapid pyrolysis-MS measurements. Furthermore, we elucidate that higher crosslinking density of the matrix polymers enhances thermal conductivity. This data-driven method promises to streamline the identification of key functional factors in complex composite materials.

Development of complete hydrometallurgical processes for gold recovery from ICs and CPUs using ionic liquids

Integrated circuits (ICs) and central processing units (CPUs), essential components of electrical and electronic equipment (EEE), are complex composite materials rich in recyclable high-value strategic and critical metals, with many in concentrations higher than in their natural ores. With gold the most valuable metal present, increase in demand for gold for EEE and its limited availability have led to a steep rise in the market price of gold, making gold recycling a high priority to meet demand. To overcome the limitations associated with conventional technologies for recycling e-waste, the use of greener technologies (ionic liquids (ILs) as leaching agents), offers greater potential for the recovery of gold from e-waste components. While previous studies have demonstrated the efficiency and feasibility of using ILs for gold recovery, these works predominantly concentrate on the extraction stage and often utilise simulated solutions, lacking the implementation of a complete process validated with real samples to effectively assess its overall effectiveness. In this work, a simulated Model Test System was used to determine the optimal leaching and extraction conditions before application to real samples. With copper being the most abundant metal in the e-waste fractions, to access the gold necessitated a two-stage pre-treatment (nitric acid leaching followed by aqua regia leaching) to ensure complete removal of copper and deliver a gold-enriched leach liquor. Gold extraction from the leach liquor was achieved by liquid-liquid extraction using Cyphos 101 (0.1 M in toluene with an O:A = 1:1, 20 °C, 150 rpm, and 15 min) and as a second process by sorption extraction with loaded resins (Amberlite XAD-7 with 300 mg of Cyphos 101/g of resins at 20 °C, 150 rpm and 3 h). In both processes, complete stripping and desorption of gold was achieved (0.5 M thiourea in 0.5 M HCl) and gold recovered, as nanoparticles of purity ≥95%, via a reduction step using a sodium borohydride solution (0.1 M NaBH4 in 0.1 M NaOH). These two hydrometallurgical processes developed can achieve overall efficiencies of ≥95% for gold recovery from real e-waste components, permit the reuse of the IL and resins up to five consecutive times, and offer a promising approach for recovery from any e-waste stream rich in gold.

Gaussian process-based nonlinearity compensation for pneumatic soft actuators

Abstract Highly compliant Pneumatic Soft Actuators (PSAs) have the potential to perform challenging tasks in a broad range of applications that require shape-adaptive capabilities. Achieving accurate tracking control for such actuators with complex geometries and material compositions typically involves many time-consuming and laborious engineering steps. In this work, we propose a data-driven learning-based control approach to address reference tracking tasks, incorporating self-adaptation in situ. We utilize a short interaction maneuver, recorded a priori, to collect the quasi-static data affected by severe hysteresis. Besides a linear feedback controller, we use two Gaussian process models to predict the feedforward control input to compensate for the nonlinearity in a one-shot learning setting. The proposed control approach demonstrates accurate tracking performance even under realistic varying configurations, such as alterations in mass and orientation, without any parameter tuning. Notably, training was achieved with only 25–50 s of experimental interaction, which emphasizes the plug-and-play capabilities in diverse real-world applications.

Pressing of Functionalized Polymer Composite Materials to Improve Mössbauer Measurement Signals.

Coordination compounds, like iron(II) triazole complexes, exhibit spin crossover (SCO) behavior at around room temperature. Therefore, they are interesting for a variety of possible applications, and it is convenient to integrate them into polymers. Due to a reduction of the iron content and thus also 57Fe content in the sample through integration in polymers, Mössbauer measurements are only possible with greater difficulty or very long measurement times without expensive enrichment of the samples with 57Fe. So, other ways of improving the Mössbauer signal for these composite materials are necessary. Therefore, we pressed these composite materials to improve the Mössbauer spectra. In this study, we synthesized an iron(II) triazole spin crossover complex and an electrospun polymer complex composite nanofiber material including the same complex. For both products, Mössbauer measurements were performed at room temperature before and after using a press to show that the complex composite is not harmed through pressing. We investigate the influence of the pressing impact on the Mössbauer measurements in the context of measurement statistics and the measured signals. We show that pressing is not connected to any changes in the sample regarding the spin and oxidation state. We present that pressing improves the statistics of the Mössbauer measurements significantly. Furthermore, we use SEM measurements and PXRD to investigate whether or not the obtained fiber mats are destroyed in the pressing process.

Wet-spinning of reduced graphene oxide composite fiber by mechanical synergistic effect with graphene scrolling method

Carbon-based fibers have attracted attention in various field owing to their exceptional properties, including high tensile strength, thermal stability, and electrical conductivity. In particular, graphene-based high-strength fibers are promising materials in aerospace, automotive, and marine sectors. Recently, the hybrid fiber, consisting of carbon nanotubes (CNTs) and graphene with enhanced toughness was reported by deflecting cracks and enabling high deformation. However, complex synthesis and structural optimization of composite fiber with two different materials make challenge for mass production. Here, we introduce a novel graphene composite fiber, consisting of reduced graphene oxide (rGO) and scrolled rGO (SrGO), showing remarkable toughness. A multidimensional-state solution with 2D rGO and 1D SrGO was obtained by using a simple sonication technique. Mass production of high-toughness composite fibers was achieved via wet-spinning, with enhanced toughness attributed to microstructure optimization by controlling the SrGO ratio. Additionally, the use of poly(vinyl alcohol) (PVA) as the matrix facilitated high deformation, resulting in a remarkable 90.7 % increase in mechanical toughness without complex composite material synthesis.

Polycaprolactone/β-Tricalcium Phosphate Composite Scaffolds with Advanced Pore Geometries Promote Human Mesenchymal Stromal Cells' Osteogenic Differentiation.

Critical-sized mandibular bone defects, arising from, for example, resections after tumor surgeries, are currently treated with autogenous bone grafts. This treatment is considered very invasive and is associated with limitations such as morbidity and graft resorption. Tissue engineering approaches propose to use 3D scaffolds that combine structural features, biomaterial properties, cells, and biomolecules to create biomimetic constructs. However, mimicking the complex anatomy and composition of the mandible poses a challenge in scaffold design. In our study, we evaluated the dual effect of complex pore geometry and material composition on the osteogenic potential of 3D printed scaffolds. The scaffolds were made of polycaprolactone (PCL) alone (TCP0), or with a high concentration of β-tricalcium phosphate (β-TCP) up to 40% w/w (TCP40), with two complex pore geometries, namely a star- (S) and a diamond-like (D) shape. Scanning electron microscopy and microcomputed tomography images confirmed high fidelity during the printing process. The D-scaffolds displayed higher compressive moduli than the corresponding S-scaffolds. TCP40 scaffolds in simulated body fluid showed deposition of minerals on the surface after 28 days. Subsequently, we assessed the differentiation of seeded bone marrow-derived human mesenchymal stromal cells (hMSCs) over 28 days. The early expression of RUNX2 in the cell nuclei confirmed the commitment toward an osteogenic phenotype. Moreover, alkaline phosphatase (ALP) activity and collagen deposition displayed an increasing trend in the D-scaffolds. Collagen type I was mainly present in the deposited extracellular matrix (ECM), confirming deposition of bone matrix. Finally, Alizarin Red staining showed successful mineralization on all the TCP40 samples, with higher values for the S-shaped scaffolds. Taken together, our study demonstrated that the complex pore architectures of scaffolds comprised TCP40 stimulated osteogenic differentiation and mineralization of hMSCs in vitro. Future research will aim to validate these findings in vivo.

Enhancing waste hemp hurd-derived anodes for sodium-ion batteries through hydrochloric acid-mediated hydrothermal pretreatment

Waste hemp hurd (WHH) was used as a sustainable feedstock for producing hard carbon-based anodes for sodium-ion batteries (SIBs). Two easily scalable production pathways were tested and compared: (1) pyrolysis (at 500 °C) and subsequent annealing at 800, 1000 or 1200 °C, and (2) hydrothermal pretreatment (at 180 °C) and subsequent annealing at the above-mentioned highest temperatures. Results indicated that when a HCl (2 mol m−3) aqueous solution was used as hydrothermal medium, the textural, structural and surface chemistry features linked to the electrochemical performance of the resulting hard carbons improved. The WHH-derived electrode produced via HCl-mediated hydrothermal pretreatment and subsequent annealing at 1000 °C showed an exceptional electrochemical performance in terms of specific capacity (535 mA h g−1 at 30 mA g−1) and rate capability (372, 156, 115, and 83 mA h g−1 at 0.1, 0.5, 1, and 2 A g−1, respectively) when an ester-based electrolyte was used (NaTFSI in EC/DMC). Using an ether-based electrolyte (NaPF6 in diglyme) improved both the ICE (from 69% to 78%) and cycling stability (85% of capacity retention after 300 cycles at 1 A g−1; 91% when current rate returned to 0.1 A g−1). In summary, relatively low-cost WHH-derived carbons are able to deliver an exceptional performance, much better than that reported so far for other biomass-derived carbons, and even close to that exhibited by more expensive and complex composite and hybrid materials.

Research on the centre-of-mass adjustment method for the head of an anthropometric test device based on a head impact biomechanics model

Head injury is the primary cause of serious lesions or death in automobile accidents. During crash tests, the mass and centre-of-mass position of the head of anthropometric test devices are crucial factors determining the accuracy of head injury test data. However, owing to the irregular shape as well as complex structure and material composition of the head of dummies, problems such as uneven mass distribution easily occur, resulting in deviations between the actual and designed positions of the centre-of-mass of the head. This study conducted research on head impact biomechanics and the centre-of-mass adjustment method for the head of dummies. Specifically, the biomimetic mechanical equivalent of the head was investigated, and head impact mechanics were analysed. Then, a predictive model was established for head drop mechanical response; the accuracy of this model was verified through head drop experiments. Based on the model, the law of centre-of-mass influence on the mechanical response of the dummy head was investigated, yielding an evaluation method for the different mechanical responses of the head. Using the rotational centre-of-mass measurement method, the mass and centre-of-mass position of the head were obtained. The distributed centre-of-mass adjustment method based on the principle of torque equilibrium was utilized to solve the deviations in the centre-of-mass position, the geometric dimensions of the counterweights and the centre-of-mass itself. Two counterweights were distributed on both sides of the internal cavity wall of the dummy head, resolving the positioning issue of the counterweights in the head cavity. The rationality of the centre-of-mass adjustment results was analysed using the predictive model for head impact mechanical response. The analysis results indicate that the centre-of-mass-adjusted dummy head better aligned with the mechanical response of the head in real collision scenarios, providing a new approach for the adjustment of the centre-of-mass of the head of dummies.

Rice Husk with PLA: 3D Filament Making and Additive Manufacturing of Samples for Potential Structural Applications.

Additive manufacturing has garnered significant attention as a versatile method for fabricating green and complex composite materials. This study delves into the fabrication of polymer composites by employing polylactic acid (PLA) in conjunction with rice husk as a reinforcing filler. The filaments were made by an extruded filament maker and then were used to make tensile and impact samples by another extrusion technology, fused deposition modeling (FDM). The structural and morphological characteristics of the composite materials were analyzed using scanning electron microscopy SEM. Results show that both the filament and samples are very reliable in producing polymer parts with this rice husk solid waste. This research contributes to increasing materials' circularity and potentially creating a local social economy around rice production, where this waste is not much used.

A deep material network approach for predicting the thermomechanical response of composites

Recent progress combining micromechanics and machine learning holds promise for accurately and rapidly predicting the mechanical behavior of complex composite materials. This study extends the Deep Material Network (DMN), a binary-tree network trained on linear direct-numerical-simulation data, to predict the thermo-elasto-viscoplastic behavior of composites. This extension incorporates the thermal expansion properties homogenization into the network’s building blocks and expands the online formulation to consider thermal boundary conditions. By comparing various implementations of these building blocks, we demonstrate the network’s extrapolation to thermomechanical problems. We then show how this extended DMN can be applied to uncertainty quantification and inverse design problems.

Use of treated municipal waste incinerator ashes as concrete aggregate after fragmentation and sorting

AbstractAnnually about 5.7 million tons of waste incinerator ash accumulate in Germany through the incineration of municipal waste. The new method of electrodynamic fragmentation allows waste incinerator ashes with complex material compositions to be broken at material interfaces and then sorted into materially pure components. The aim of current ASHCON research project is to substitute natural aggregate of the grain fraction 2/8 mm in conventional formulations for ready‐mixed concrete and concrete blocks by these secondary raw materials in order to keep them within the material cycle and reduce the use of primary raw materials. Since the utilization of fragmented waste incinerator ashes in concrete must be below the limit values with regard to possible pollutant concentrations (e.g. heavy metal concentrations), the suitability of a so‐called non‐destructive neutronic analysis method on real samples is also being investigated within the ASHCON project. The first results of sample collection, preparation and analysis as well as material properties of the produced concretes with the implementation of mineral residues from waste incinerator ashes are presented in this paper.

Design Strategy for Improving Detection Sensitivity in a Bromoplumbate Photochromic Semiconductor.

Reducing the dark current of photodetectors is an important strategy for enhancing the detection sensitivity, but hampered by the manufacturing cost due to the need for controlling the complex material composition and processing intricate interface. This study reports a new single-component photochromic semiconductor, [(HDMA)4(Pb3Br10)(PhSQ)2]n (1, HDMA = dimethylamine cation, PhSQ = 1-(4-sulfophenyl)-4,4'-bipyridinium), by introducing a redox-active monosubstituted viologen zwitterion into inorganic semiconducting skeleton. It features yellow to green coloration after UV irradiation with the sharply dropping intrinsic conductivity of 14.6-fold, and the photodetection detection sensitivity gain successfully doubles. The reason of decreasing conductivity originates from the increasing the band gap of the inorganic semiconducting component and formation of Frenkel excitons with strong Coulomb interactions, thereby decreasing the concentration of thermally excited intrinsic carriers.

Gradient enhanced gaussian process regression for constitutive modelling in finite strain hyperelasticity

This paper introduces a metamodelling technique that leverages gradient-enhanced Gaussian process regression (also known as gradient-enhanced Kriging), effectively emulating the response of diverse hyperelastic strain energy densities. The approach adopted incorporates principal invariants as inputs for the surrogate of the strain energy density. This integration enables the surrogate to inherently enforce fundamental physical constraints, such as material frame indifference and material symmetry, right from the outset. The proposed approach provides accurate interpolation for energy and the first Piola–Kirchhoff stress tensor (e.g. first order derivatives with respect to inputs). The paper presents three notable innovations. Firstly, it introduces the utilisation of Gradient-Enhanced Kriging to approximate a diverse range of phenomenological models, encompassing numerous isotropic hyperelastic strain energies and a transversely isotropic potential. Secondly, this study marks the inaugural application of this technique for approximating the effective response of composite materials. This includes rank-one laminates, for which analytical solutions are feasible. However, it also encompasses more complex composite materials characterised by a Representative Volume Element (RVE) comprising an elastomeric matrix with a centred spherical inclusion. This extension opens the door for future application of this technique to various RVE types, facilitating efficient three-dimensional computational analyses at the macro-scale of such composite materials, significantly reducing computational time compared to FEM2. The third innovation, facilitated by the integration of these surrogate models into a 3D Finite Element computational framework, lies in the assessment of these models scenarios encompassing intricate cases of extreme twisting and more importantly, buckling instabilities in thin-walled structures, thereby highlighting both the practical applicability and robustness of the proposed approach.

Complex TiC-Ni-based composites joined to steel support by thermal explosion under load: synthesis, microstructure and tribological behavior

ABSTRACT The combustion in thermal explosion mode of reactive mixtures of Ti–Ni–graphite(carbides, borides, oxides), under load, was used to produce complex composite materials, densified and joined to a C55 carbon steel support. The ignition of the exothermic reaction, carried out thanks to the rapid high-frequency heating of a green compact up to 1573 K, was followed by an isothermal holding at 1373 K for 360 s. This procedure ensured a perfect mechanical assembly between the composite material and the steel substrate. SEM analysis and concentration profiles carried out at the interface testified to the interdiffusion of iron and titanium atoms between the two materials. The maximum combustion temperature (Tmax.) exceeding 2200 K induced the appearance of a liquid phase that assisted densification and joining, and in which a part of the additions was dissolved before cooling. The starting chemical composition of reactive mixtures largely determined the microstructure, hardness and tribological behavior of the composites after the process. Thereby, the maximum hardness (1235 HV0.15) and the lowest wear rate (1.824 × 10−6 mm3.N−1.m−1) were obtained in the sample containing TiC, Al2O3 and TiB2 hard phases. The manufactured samples exhibit no deterioration of the composite by spalling, regardless of the starting composition.

Vibrational timber characterization through the use of model updating

The characterization of orthotropic materials has challenged the vibration and acoustics community for quite some time. Complex composite materials such as wooden structures require attention to factors including moisture, grain boundaries in addition to macroscopic features. Here we devise a basic model developed by measuring the vibrational response in two separate axes to determine the material characteristics of a timber dowel. A proposed benchtop procedure utilises vibrometers and accelerometers to gather data before the updating process, for which, FEMtools was used. Based on the input material parameters, uncovered by previous studies, provide a starting point for the model updating procedure where experimental mode shapes and frequency responses are correlated to the finite element model. With the focus on radiata pine, the results show radial and tangential values converge similar to previous literature but with variation in the longitudinal direction and shear planes. Overall, this study provides a solid foundation to the characterization process of orthotropic materials like timber which can be further expanded into fields of structural health monitoring, damage detection and potential use in digital twins. The authors acknowledge the support of the Australian Research Council Linkage Project LP200301196.