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Presents development and characterisation of a new metal/polymer composite material for use in fused deposition modelling (FDM) rapid prototyping process with the aim of application to direct rapid tooling. The work represents a major development in reducing the cost and time in rapid tooling.

The material consists of iron particles in a nylon type matrix. The detailed formulation and characterisation of the thermal properties of the various combinations of the new composites are investigated experimentally. Results are compared with other metal/polymer composites used in rapid tooling.

The feedstock filaments of this composite have been produced and used successfully in the unmodified FDM system for direct rapid tooling of injection moulding inserts. Thermal properties are found to be acceptable for rapid tooling applications for injection moulding.

Introduces an entirely new metal based composite material for direct rapid tooling application using FDM RP system with desired thermal properties and characteristics. This will reduce the cost and time of manufacturing tooling inserts and dies for injection moulding.

This study aims to investigate the tensile strength and elastic modulus of custom-designed polymer composites developed using voxel-based design. This study also evaluates theoretical models, such as the rule of mixtures, Halpin–Tsai model, Cox–Krenchel model and the Young–Beaumont model and the ability to predict the mechanical properties of particle-reinforced composites based on changes in the design of rigid particles at the microscale within a flexible polymer matrix.

This study leverages the PolyJet process for voxel-printing capabilities and a design of experiments approach to define the microstructural design elements (i.e. aspect ratio, orientation, size and volume fraction) used to create custom-designed composites.

The comparison between the predictions and experimental results helps identify appropriate methods for determining the mechanical properties of custom-designed composites ensuring informed design decisions for improved mechanical properties.

This work centers on multimaterial additive manufacturing leveraging design freedom and material complexity to create a wide range of composite materials. This study highlights the importance of identifying the process, structure and property relationships in material design.

This article aims to study the tensile properties of a functionally graded composite structure with Al–18wt%Si alloy as the matrix material and silicon carbide (SiC) particles as the reinforcing element. More specifically, the study's primary objective is to optimize the composition of the material elements using a robust statistical approach.

In this research, the composite material is fabricated using a combination of stir casting and the centrifugal casting technique. Moreover, the test specimen required to study the tensile strength are prepared according to the ASTM (American Society for Testing and Materials) standards. Eventually, optimal composition to maximize the tensile property of the material is determined using the mixture design approach.

The investigation results imply that the addition of the SiC plays a crucial role in increasing the tensile strength of the composite. The optical microstructural images of the composite show the adequate distribution of the reinforcing particles with the matrix. The proposed regression model shows better predictability of tensile strength. In addition, the methodology aids in optimizing the mixture component values to maximize the tensile strength of the produced functionally graded composite structure.

Little work has been reported so far where a hypereutectic Al–Si alloy is considered the matrix material to produce the composite structure. The article attempts to make a composite structure by using a combination of stir casting and centrifugal casting. Furthermore, it employs the mixture design to optimize the composition and predict the model of the study, which is one of a kind in the field of material science.

PolyJet technology allows printing complex multi-material composite configurations using Voxel digital designs' capability, thus allowing rapid prototyping of 3D printed structural parts. This paper aims to investigate the processing and mechanical characteristics of composite material configurations formed from soft and hard materials with different distributions and sizes via voxel digital print design.

Voxels are extruded representations of pixels and represent different material information similar to each pixel representing colors in digital images. Each geometric region of a digitally designed part represented by a voxel can be printed with a different material. Multi-material composite part configurations were formed and rapidly prototyped using a PolyJet printer Stratasys J750. A design of experiments composite part configuration of a soft material (Tango Plus) within a hard material matrix (Vero Black) was studied. Composite structures with different hard and soft material distributions, but at the same volume fractions of hard and soft materials, were rapidly prototyped via PolyJet printing through developed Voxel digital printing designs. The tensile behavior of these formed composite material configurations was studied.

Processing and mechanical behavior characteristics depend on materials in different regions and their distributions. Tensile characterization obtained the fracture energy, tensile strength, modulus and failure strength of different hard-soft composite systems. Mechanical properties and behavior of all different composite material systems are compared.

Tensile characteristics correlate to digital voxel designs that play a critical role in additive manufacturing, in addition to the formed material composition and distributions.

Results clearly indicate that multi-material composite systems with various tensile mechanical properties could be created using voxel printing by engineering the design of material distributions, and sizes. The important parameters such as inclusion size and distribution can easily be controlled within all slices via voxel digital designs in PolyJet printing. Therefore, engineers and designers can manipulate entire morphology and material at each voxel level, and different prototype morphologies can be created with the same voxel digital design. In addition, difficulties from AM process with voxel printing for such material designs is addressed, and effective digital solutions were used for successful prototypes. Some of these difficulties are extra support material or printing the part with different dimension than it designed to achieve the final part dimension fidelity. Present work addressed and resolved such issued and provided cyber based software solutions using CAD and voxel discretization. All these increase broad adaptability of PolyJet AM in industry for prototyping and end-use.

The issues concerning the prediction of changes in properties of polymer materials as a result of adding reinforcing fibers are currently widely discussed in the field of polymer material processing. This paper aims to present strengths and weaknesses of composites based on polymer materials strengthened with fibers. It touches upon composite cracking at the junction of a matrix and its reinforcement. It also discusses the analysis of changes in properties of chosen materials as a result of adding reinforcing fibers. The paper shows improvement in the strength of polymer materials with fiber addition, which is extremely important, because these types of composites are used in the aerospace, automotive and electrical engineering industries.

Comparing the properties of matrix strength with fiber properties is practically impossible. Thus, fiber tensile strength and composite tensile strength shall be compared (González et al., 2011): tensile (glass fiber GF) = 900 [MPa], elongation ΔL≈ 0; yield point (polyamide 66) = 70−90 [MPa], elongation Δ[%] = 3,5-18; tensile (polyamide 66 + 15% GF) = 80-125 [MPa], elongation Δ[%] ≈ 0; tensile (polyamide 66 + 30% GF) = 190 [MPa], elongation Δ[%] ≈ 0; yield point (polyamide 6) = 45-85 [MPa], elongation Δ[%] = 4-15; tensile (polyamide 6 + 15% GF) = 80-125 [MPa], elongation Δ[%] ≈ 0; tensile (polyamide 6 + 30% GF) = 95-130 [MPa] elongation Δ[%] ≈ 0. Comparison of properties of selected polymers and composites is presented in Tables 1−10 and Figures 1 and 2. The measurement methodology is presented in detail in the paper Kula et al. (2018). The increase in fiber content (to the extent discussed) leads to the increase in yield strength stresses and hardness. The value of yield strength for polyamide with the addition of fiberglass grows gradually with the increase in fiber content. The hardness of the composite of polyamide with glass balls increases together with the increase in reinforcement content. The changes of these values do not occur linearly. The increase in fiber content has a slight impact on density change (the increase of about 1 g/mm³ per 10 per cent).

The use of polymers as a matrix allows to give composites features such as: lightness, corrosion resistance, damping ability, good electrical insulation and thermal and easy shaping. Polymers used as a matrix perform the following functions in composites: give the desired shape to the products, allow transferring loads to fibers, shape thermal, chemical and flammable properties of composites and increase the possibilities of making composites. Fiber-reinforced polymer composites are the effect of searching for new construction materials. Glass fibers show tensile strength, stiffness and brittleness, while the polymer matrix has viscoelastic properties. Glass fibers have a uniform shape and dimensions. Fiber-reinforced composites are therefore used to increase strength and stiffness of materials. Polymers have low tensile strength, exhibit high deformability. Polymers reinforced by glass fiber have a high modulus of elasticity and therefore provide better the mechanical properties of the material. Composites with glass fibers do not exhibit deformations in front of cracking. An increase in the content of glass fiber in composites increases the tensile strength of the material. Polymers reinforced by glass fiber are currently one of the most important construction materials and are widely used in the aerospace, automotive and electro-technical industries.

The paper presents the test results for polyethylene composites with 25 per cent and 50 per cent filler coming from recycled car carpets of various car makes. The tests included using differential scanning calorimetry, testing material hardness, material tensile strength and their dynamic mechanical properties.

The purpose of this paper is to investigate the concept of new drill bit geometry adjusted to a given composite type. This paper explores the possibility of drilling in composites without negative effects such as: delamination, rapid tool wear, matrix burns, pulling out of fibers, etc.

Appropriate modification of drill bit geometries applied to composite materials include, among other things: modifications of point angles, reduction of chisel edge width, modification of drill margins and proper preparation of drill bit corners.

Description of tool geometry for drilling of different types of composites, in particular drilling in parts included free grain surfaces but also drilling at a different angle than 90°.

Geometrical details of the tool for drilling are depended on the type of composite.

Making of montage holes in parts made of composites without negative effects during drilling.

Analysis of the current state of knowledge shows that there are insufficient solutions in terms of new drill geometry for drilling of composites. Existing solutions do not guarantee adequate stability and repeatability of the cutting process. It is necessary to create new geometry drills permit the elimination of negative phenomena during drilling.

The ability of light‐weight all fiber‐reinforced polymer‐matrix composite armor and hybrid composite‐based armor hard‐faced with ceramic tiles to withstand the impact of a non‐Armor‐ Piercing (non‐AP) and AP projectiles is investigated using a transient non‐linear dynamics computational analysis. The results obtained confirm experimental findings that the all‐composite armor, while being able to successfully defeat non‐AP threats, provides very little protection against AP projectiles. In the case of the hybrid armor, it is found that, at a fixed overall areal density of the armor, there is an optimal ratio of the ceramic‐to‐composite areal densities which is associated with a maximum ballistic armor performance against AP threats. The results obtained are rationalized using an analysis based on the shock/blast wave reflection and transmission behavior at the hard‐face/air, hard‐face/backing and backing/air interfaces, projectiles’ wear and erosion and the intrinsic properties of the constituent materials of the armor and the projectiles.

The purpose of this paper is to study the effect of the addition of silicon carbide (SiC) microparticles and their contributions regarding the tensile and shear properties of the T800 fiber reinforced polymer composite at various fiber volume fractions. The tensile and shear properties of the hybrid composites where continuous T800 fibers are used as reinforcements in an epoxy matrix embedded with SiC microparticles have been studied.

The results were obtained by implementing a micromechanics approach assuming a uniform distribution of reinforcements and considering one unit cell from the whole array. Using the two-step homogenization process, the properties of the materials were determined by using the finite element analysis (FEA). The predicted elastic properties from FEA were compared with the analytical results. The analytical models were implemented in the MATLAB Software. The FEA was performed in ANSYS APDL.

The mechanical properties of the hybrid composite had increased when compared with the properties of the conventional FRP. The results suggest that SiC particles are a good reinforcement for enhancing the transverse and shear properties of the considered fiber reinforced epoxy composite. The microparticle embedment has significant effect on the transverse tensile properties as well as in-plane and out-of-plane shear properties.

This is significant because improving the properties of the composite materials using different methods is of high interest in the materials community. Using this study people can work on the process of including different type of microparticles in to their composite designs and improve their performance characteristics. The major influence of the particles can be seen only at lower volume fractions of the fiber in the composite. Only FEA and analytical methods were used for the study.

Material property improvements lead to more advanced designs for aerospace and defense structures, which allow for high performance under unpredictable conditions.

This type of study proves that the embedment of different microparticles is a method that can be used for improving the properties of the composite materials. The improvement of the transverse and shear properties will be useful especially in the design of shell structures in the different engineering applications.

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Mycelium is an upcoming bio-based alternative material that has various applications in different industries. Mycelium materials used as composites, leather, construction materials and some are even available for commercial purposes. However, there was not much research found when it came to the application of mycelium as a textile alternative. The purpose of this paper is to examine the potential of mycelium in the textile industry and its possible applications.

This review consolidates literature that refers the two major methods used in fungal mycelium production namely; as a composite and as a pure self-grown mycelium sheet. The study compared the current research status in this respective field and reported the scope in the pure mycelium development.

The results of the review reported that several research works are performed in composite production with different feedstock. The production methods and product development steps were well established for several applications from home utilities to construction materials. Whereas, in the case of self-grown mycelium sheet production only limited research works were found. Though the possibilities of engineered composite sheets are developed with various properties, research on self-grown pure mycelium sheets are at infant stage. Sensitive production methods, lower tensile, tearing, poor handle properties with brittle structure and non-uniformity in thickness are noted as limitations. Sustainable nature, self-grown three-dimensional nano-fibril network with porous structure are found to be advantageous.

The solid culture method was identified as a potential method to develop a sheet-like self-grown mycelium with different dimensions. The review results clearly show the lack of research in the direct application of self-grown pure mycelium area concerning feedstock material, fungal species selection and characterization of the developed product. Addressing the existing limitations will yield a sustainable textile material for fashion and textile industry with great potential.