In recent years, both industrial and academic world are focussing their attention toward the development of sustainable composites, reinforced with natural fibres. In particular, among the natural ...fibres (i.e. animal, vegetable or mineral) that can be used as reinforcement, the basalt ones represent the most interesting for their properties. The aim of this review is to illustrate the results of research on this topical subject. In the introduction, mechanical, thermal and chemical properties of basalt fibre have been reviewed. Moreover, its main manufacturing technologies have been described. Then, the effect of using this mineral fibre as reinforcement of different matrices as polymer (both thermoplastic and thermoset), metal and concrete has been presented. Furthermore, an overview on the application of this fibre in biodegradable matrix composites and in hybrid composites has been provided. Finally, the studies on the industrial applications of basalt fibre reinforced composites have been reviewed.
Nanocellulose is often being regarded as the next generation renewable reinforcement for the production of high performance biocomposites. This feature article reviews the various nanocellulose ...reinforced polymer composites reported in literature and discusses the potential of nanocellulose as reinforcement for the production of renewable high performance polymer nanocomposites. The theoretical and experimentally determined tensile properties of nanocellulose are also reviewed. In addition to this, the reinforcing ability of BC and NFC is juxtaposed. In order to analyse the various cellulose-reinforced polymer nanocomposites reported in literature, Cox–Krenchel and rule-of-mixture models have been used to elucidate the potential of nanocellulose in composite applications. There may be potential for improvement since the tensile modulus and strength of most cellulose nanocomposites reported in literature scale linearly with the tensile modulus and strength of the cellulose nanopaper structures. Better dispersion of individual cellulose nanofibres in the polymer matrix may improve composite properties.
Composites have been increasingly used in various structural components in the aerospace, marine, automotive, and wind energy sectors. Composites’ material characterization is a vital part of the ...product development and production process. Physical, mechanical, and chemical characterization helps developers to further their understanding of products and materials, thus ensuring quality control. Achieving an in-depth understanding and consequent improvement of the general performance of these materials, however, still requires complex material modeling and simulation tools, which are often multiscale and encompass multiphysics. This Special Issue is aimed at soliciting promising, recent developments in composite modeling, simulation, and characterization, in both design and manufacturing areas, including experimental as well as industrial-scale case studies. All submitted manuscripts will undergo a rigorous review and will only be considered for publication if they meet journal standards.
Overall performance of curvilinear fiber reinforced composite structures (CFRCSs) can be designed by adjusting the local fiber orientation and content. In this paper, an optimized design method based ...on stress gradient distribution for CFRCSs was proposed to improve the efficiency in strength of continuous fiber reinforced composites. The mechanism of fiber content regulation in continuous fiber reinforced composites 3D printing was studied. The adaptive feed calculation method of resin was proposed, and the 3D printing of CFRCSs was realized. A 3D printed composite perforated plate with a hole under tensile loading was optimized and fabricated to verify the effectiveness of the proposed methods. After the optimized design, the maximum stress concentration factor was reduced by 36%, and the ultimate tensile strength was increased by 42%. Through the proposed optimization design method, the fiber content distribution corresponds to the stress distribution, and the fiber direction distribution corresponds to the maximum principal stress direction distribution. At the same time, the stress was redistributed to reduce the stress concentration. Therefore, the ultimate strength was improved. The optimized design method and 3D printing method of CFRCSs have potential application prospects in aerospace, automotive and other fields.
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The production of continuous carbon fibre composites using a fused deposition modelling (FDM) method has addressed the problem of low mechanical performance of raw- or short-fibre reinforced polymer ...parts fabricated by the same process, due to the excellent specific strength and stiffness of continuous fibres. However, one key issue of 3D printed polymers or fibre-reinforced polymers is the formation of microscopic voids between individual filaments and within the filaments during the FDM process. This study aims to quantify the adverse effects of voids on 3D printed continuous fibre-reinforced polymer composites. Optical microscopy and micro-CT are used to quantify the void content in continuous CF/PA6 composites fabricated on a 3D printing platform. As a benchmark, 3D printed CF/PA6 composites with the same printing configurations were further processed by compression moulding (CM) with thickness controlled to achieve the minimum void content. Apart from tensile and three-point bending tests in the longitudinal and transverse directions, the study also evaluated the Mode I interlaminar fracture toughness of CF/PA6 composites. By revealing the substantial adverse effects of the microscopic voids in 3D printed composites, this study articulates the critical importance of developing in-process techniques during 3D printing to decrease the void content within the continuous fibre reinforced composites, for the sake of expanding practical applications of 3D printed continuous fibre composites.
Additive manufacturing is distinguished from traditional manufacturing techniques such as casting and machining by its ability to handle complex shapes with great design flexibility and without the ...typical waste. Although this technique has been mainly used for rapid prototyping, interest is growing in direct manufacture of actual parts. For wide spread application of 3D additive manufacturing, both techniques and feedstock materials require improvements to meet the mechanical requirements of load-bearing components. Here, we investigated short fiber (0.2–0.4mm) reinforced acrylonitrile–butadiene–styrene composites as a feedstock for 3D-printing in terms of their processibility, microstructure and mechanical performance. The additive components are also compared with traditional compression molded composites. The tensile strength and modulus of 3D-printed samples increased ∼115% and ∼700%, respectively. 3D-printing yielded samples with very high fiber orientation in the printing direction (up to 91.5%), whereas, compression molding process yielded samples with significantly lower fiber orientation. Microstructure–mechanical property relationships revealed that although a relatively high porosity is observed in 3D-printed composites as compared to those produced by the conventional compression molding technique, they both exhibited comparable tensile strength and modulus. This phenomenon is explained based on the changes in fiber orientation, dispersion and void formation.
Wear of total hip prosthesis is a significant clinical problem that nowadays involves a growing number of patients. To acquire further knowledge on the tribological phenomena that involve hip ...prosthesis, wear tests are conducted on new biomaterials to increase materials life in orthopaedic implants. Advances in biomaterials for biomedical purposes have enhanced in the last years evolving in new improved ceramic and polymeric materials producing the so-called composite materials.
This paper aims to review the evolution and the current state of the art of the ceramics composites and polymers commonly used in orthopaedic field as hip joint implants. This is specified through a schematic overview by describing, in particular, the evolution of various composites materials. The authors propose commentary on the evolution and current use of biomaterials for orthopaedic application on the evolution and actually used biomaterials for orthopaedic applications.
Deployable structures are typically made of thin membranes and slender elements, which often require foldable – yet stiff – mechanical properties. The use of carbon fiber reinforced polymer (CFRP) ...composites for such deployable structures has been limited due to the their rigid and unfoldable nature in general. Here, we design, fabricate, and demonstrate foldable – yet stiff – structures made of CFRP composites. To achieve this, we leverage origami design principles based on the Tachi-Miura-Polyhedron (TMP) architecture. To manufacture TMP structures, we devise a unique vacuum-bag-only composite fabrication method by using compliant urethane epoxies impregnated into woven glass fiber layers on which pre-made CFRP tiles are positioned. We show the resulting structures feature self-deployability, high compactness, and deterministic force–displacement characterization. Potential applications of the proposed composite origami are abundant, including deployable habitats for space exploration and disaster relief, deployable solar arrays and antennas, actively-controlled aerodynamic surfaces, and impact mitigation structures.
Frictional characteristics of glass fiber reinforced polymer (GFRP) composites are of technological interests for reducing wear in circumstances where they are applied. Graphene oxide (GO) is one 2D ...nanomaterial with an excellent lubricating effect. However, no work has been reported yet on the effects of GO coating on the frictional characteristics of GFRP composites. In this work, GO was grafted on GFs by a surface treatment method via silane coupling agent. Uncoated and coated unidirectional GF reinforced epoxy composites were prepared using a hot press process. The frictional characteristics of GF reinforced composites were investigated in two directions parallel and perpendicular to fiber direction by the pin-on-disk method under the pressure of 5–30 N at the disk rotating speed of 50–200 rpm. The results showed that the frictional stability was greatly improved by grafting GO on GFs. The friction coefficient of GO-coated glass fiber reinforced polymer (GO-coated GFRP) composite was generally lower than that of the GFRP composite under a low pressure of 5 N and showed the lowest average friction coefficient of about 0.10 at the rotating speed of 100 rpm in the direction parallel to the fiber alignment. For the raw glass fiber reinforced composite, the friction coefficient is high under low pressures at low rotation speeds while this tendency is inverse for the GO-coated GFRP composite. In addition, the anisotropy of the friction characteristics is not obvious under low pressures but becomes obvious at high pressures for both GFRP and GO-coated GFRP composites.
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