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The purpose of this paper is to investigate the effect of doping element on the structural, thermal properties, mechanical performance and the failure mechanism of hexagonal nano boron nitride (h-BN)-reinforced basalt fabric (BF)/epoxy composites produced by hand lay-up and vacuum bagging technique. h-BN particles doped to composite materials increased the tensile, bending and impact strength of the composite at certain rates while 1 Wt. % h- BN addition shows the highest tensile and flexural strength.

The epoxy resin was doped with h-BN nanopowder at the certain rates (0, 1, 2 and 4 Wt.%) and the epoxy: hardener ratios used in the study were selected as 80%: 20% by weight. Then, with the aid of a roller by hand lay-up method, a mixture of epoxy + hardeners containing nanoparticles and nanoparticle-free were fed onto BFs, 12 layers of each dimension 30 cm × 30 cm. The surplus epoxy resin was moved away from the composite sheets using the vacuum bagging process and left to cure at room temperature for 24 h. ASTM D3039 for tensile, D7264 for three-point bending and D256 for Izod impact test were performed for the mechanical tests. After the tensile test, the morphologies of the fracture surface were examined with a stereomicroscope and various failure mechanisms are highlighted.

In this study, a series of basalt/epoxy composites with h-BN nanopowders have been prepared to identify the effect of filler ratio on mechanical properties. It has been known from the results of mechanical experiments that the addition of h-BN improves the mechanical performance of materials at a certain rate. The tensile and flexural strengths of h-BN doped composites, increase for concentrations of 1 Wt.% h-BN, but decrease with the increasing content of it. The basalt/epoxy resin composite with higher mechanical properties could be a potential material in the automotive and aerospace industries.

The aim of this study is to contribute to literature within the context of this new combination of composites and their mechanical properties, failure mechanisms. It presents detailed characterization of each composite by using X-ray differaction (XRD), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy.

This study aims to systematically compare the effect of increasing fiber–matrix interface adhesion and matrix toughness in layered composite materials.

Silane ((3-glycidyloxypropyl) trimethoxysilane) was applied to strengthen the fiber–matrix interface connection in e-glass/epoxy laminated composite material. Using a cationic surfactant, 0.1% multi-walled carbon nanotubes (CNTs) were added to the matrix in two different ways, by with and without chemical functionalization using the vacuum infusion method.

In the results obtained from the three-point bending test specimens, it was determined that the synergistic effect of silane application and non-functionalized CNT in the matrix was higher in terms of flexural modulus and strength values.

The functionalization of multi-walled CNT did not give the expected results because of reasons such as viscosity increase and agglomeration in the matrix.

In this study, a simple model for normalization and prediction purposes was developed, which allows the determination of the flexural modulus and un-notched flexural strength values from one test result of the notched specimen. A systematic comparison was performed by varying each parameter in the composite material.

The purpose of this paper is to investigate cotton fabric behavior that is exposed to radar waves between selected operation frequencies as an alternative radar-absorbing material (RAM) response. Cotton fabric biocomposite materials were compared with carbon fabric composite materials, which are good absorbers, in terms of mechanical and electromagnetic (EM) properties for that purpose.

The laminated composite plates were manufactured by using a vacuum infusion process. The EM tests were experimentally performed with a vector network analyzer to measure reflection, transmission and absorption ability of cotton fabric, carbon fabric and cotton–carbon fabric (side by side) composite plates between 3 and 18 GHz. The tensile and low-velocity impact tests were carried out to compare the mechanical properties of cotton fabric and carbon fabric composite plates. A scanning electron microscope was used for viewing the topographical features of fracture surfaces.

The cotton fabric composite plate exhibits low mechanical values, but it gives higher EM wave absorption values than the carbon fabric composite plate in certain frequency ranges. Comparing the EM absorption properties of the combination of cotton and carbon composites with those of the carbon composite alone, it appears that the cotton–carbon combination can be considered as a better absorber than the carbon composite in a frequency range from 12 to 18 GHz at Ku band.

This paper shows how cotton, which is a natural and easily supplied low-cost raw material, can be evaluated as a RAM.

The purpose of this study is to obtain strong materials with multiwall carbon nanotubes (MWCNTs) doped and investigate laser cut of MWCNTs also find the effect of the laser cutting parameters on composite materials.

The laminated composite plates were manufactured by using a vacuum infusion process. The mechanical properties of the composite materials produced were determined according to American Society for Testing and Materials (ASTM) D3039M, ASTM D3171, ASTM D 792 and ASTM D2583. A 130 Watts carbondioxide (CO₂) laser cutting machine was used for drilling the two different composite plates with a thickness of 1.6–1.5 mm. Three variables were considered as process parameters including laser power (in three levels of 84.50, 104.00 and 127.40 W), cutting speed (in three levels of 4, 6, 8 mm/s) and 14 mm fixed focal position.

The fibers could not be cut due to insufficient melting in the experiments performed using 84.50 and 104.00 W laser power but the cutting was successfully completed when the laser power was 127.40 W. However, as the cutting speed increased, the contact time of the laser beam with the material decreased, so the kerf decreased, but the increased laser power created a thermal effect, causing an increase in hardness around the cutting surface. This increase was lower in MWCNTs doped composites compared to pure composites. It has been found that the addition of nanoparticles to layered glass fiber composite materials played an effective role in the strength of the material and affected the CO₂ laser cutting quality.

This study is a unique study in which the CO₂ laser cutting method of MWCNT-doped composite materials was investigated and the machinability without cutting errors, such as delamination, splitting, distortion and burring using the most suitable laser cutting parameters was revealed.

The purpose of this paper is to investigate the effect of doping element on the microwave absorption performance of hexagonal nano boron nitride (h-nBN)-reinforced basalt fabric (BF)/epoxy composites. A new type of hybrid composite that will be produced by the use of boron nitride as an additive that leads to increased radar absorption capability will be developed and a new material that can be used in aeronautical radar applications.

This study is focused on the microwave absorption properties of h-nBN doped basalt fabric-reinforced epoxy composites. Basalt fabric (BF)/epoxy composites (pure composites) and the BF/h-nBN (1 Wt.% h-nBN doped composites) hybrid composites were fabricated by vacuum infusion method. Phase identification of the composites were performed using X-ray diffraction (XRD), the 2θ scan range was from 10 to 60 with the scanning speed of 3°/min and surface morphologies of the composites were investigated using scanning electron microscopy (SEM). Microwave properties of samples were investigated through transmission/reflection measurements in Agilent brand 2-Port PNA-L Network Analyzer in the frequency range of 3–18 GHz. The prepared sample is positioned between two horn antennas with and without metal plate.

Experimental results show that h-nBN doped composite was synthesized successfully and the produced hexagonal nano boron nitride-added fiber laminated composite material has good absorption behavior when they are used with metallic sheets and good for isolation applications at many points in the 3–18 GHz band.

This paper will contribute to the literature on the use of basalt fabric, which are new types of fibers, and hexagonal nano boron nitride and the effects of boron nitride on radar absorption properties of composite material. It presents detail characterization of each composite by using XRD and scanning electron microscopy.