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Composite materials have become prominent in the aerospace, automotive, wind energy, biomedical, and machine tool industries. This has demanded the evaluation of the dynamic mechanical and tribological behaviour of composites to understand their performance and ensure their reliability and safety in varied operating conditions. In this study, the effect of halloysite nano-clay addition on the dynamic mechanical and tribological properties of the carbon/glass hybrid composites was investigated. The composites were produced with the vacuum assisted resin infusion process. by varying the content of halloysite nano-clay (1, 3, and 5 wt%). The dynamic mechanical properties of the manufactured composites were examined at temperatures ranging from 30 °C to 180 °C. The tribological properties of the specimens were assessed by varying the applied load (10, 20, and 30 N), sliding speed (1.5, 3, and 4.5 m/s) and sliding distance (500, 1000, and 1500 m). Box-Behnken design was utilized to optimize the number of experiments. The results showed that the halloysite-added samples had better dynamic mechanical and tribological properties than the carbon/glass hybrid composites. Especially, hybrid composites containing 3 wt% halloysite outperformed the other composites investigated. A scanning electron microscope (SEM) was used to examine the worn surface and wreckage in the investigated composite specimens.

This paper reports the mechanical properties of PLA composites incorporated with tamarind and date seed Micro fillers. The composites were manufactured through compression molding technique. The tensile results showed that the seed filler reinforcement has significantly improved the tensile strength of PLA matrix. The particulate reinforcements of both tamarind and palm almost doubled the flexural and impact strength of PLA matrix. Moreover, the date seed powder incorporated composites showed 34.68% improvement in micro hardness but the tamarind seed powder composite showed only marginal improvement (9.82%) when compared with neat PLA. Furthermore, the outcomes revealed that the wt.% of fillers play a noteworthy role in deciding the properties of the PLA composites.

In this work, the influence of hybridizing jute and carbon fibers on the mechanical properties and water absorption behavior of polyester composites was evaluated. The composites were fabricated by using compression molding technique with discrete of overall fiber weight fraction, being pure jute or pure carbon fiber or hybrid. The outcomes of the study revealed that the jute fiber composites have lower mechanical properties and higher water absorption rate when compared with carbon fiber composites. While, the combined effect enhanced the mechanical property (tensile strength of 136.3 MPa, tensile modulus of 3403 MPa, flexural strength of 175.84 MPa, flexural modulus of 9350 MPa and impact strength of 47.43 kJ/m2) and reduced the moisture absorption rate and have good interfacial bonding with polyester which was confirmed in the morphological investigation using scanning electron microscopy. Furthermore, the mechanism of fracture in mechanical-tested samples was observed through scanning electron microscopic images. All the composites developed in the work was followed the Fickian behavior of water absorption.

Natural fibers are gaining popularity among researchers and academics for use in polymer composites due to their environmental friendliness and long-term viability.A new series of green composites using chicken feather fiber (CFF) and jute as reinforcing materials in a polypropylene resin-based polymer matrixwere used to fabricate the hybrid composites. This paper examines the impact of molding pressure, temperature, and time on the tensile strength and water absorption characteristics of compression molded hybrid composites. The findings of experiments undertaken to evaluate hybrid composites produced with different fiber fractions and processing parameters are discussed in this paper.When the composites’ overall tensile strength was compared, the 100% Jute fiber composite had the highest tensile strength when the maximum pressure, temperature, and time were kept constant. Temperature and pressure have a considerable impact on composite sample tensile strength, whereas time has little influence.As predicted, raising the jute weight percentage in composites increases water absorption.

Natural fibers have the potential to replace artificial fibers in structural applications. The abrasive wear performance of natural fiber–reinforced polymer composite has not been investigated in many studies. This study discusses the specific wear rate of Cissus quadrangularis stem fiber (CQSF)/epoxy with coconut shell ash (CSA) composite using a three-body rubber wheel wear test rig. The results were analyzed by using Taguchi L9 orthogonal array. The input parameters are velocities (0.75, 1.5, and 2.25 m/s), abrading distances (400, 600, and 800 m), applied loads (10, 20, and 30 N) and CSA filler (0, 5, and 10 wt.%), and the output response is specific wear rate. The average mean signal-to-noise (S/N) ratio under ‘lower-the-best’ condition for specific wear rate is 35.54 dB. The filler addition significantly reduced the specific wear rate at 5 wt.% of CSA addition. The influence of filler on specific wear rate is higher than other input parameters followed by load, abrasive distance, and velocity. The experimental and predicted values of the specific wear rate for the optimum input parameters were 5.36 $$ \times $$ 10–3 and 5.17 $$ \times $$ 10–3 mm3/Nm. The worn surfaces were examined with the help of scanning electron microscope (SEM) images.

This research work focuses on the wear characteristics of hybrid composites prepared using Sisal fiber (SF) /Pineapple fiber (PF) and Pineapple fly ash (PA) in various wt.%. Linear reciprocating tribometer was used for determining the Specific Wear Rate (SWR) and Coefficient of Friction (CoF) of the hybrid composites. The XRF results of PA filler showed the existence of silica (64.43%) and aluminum oxide (10.03%) in a major percentage. The hybrid fiber combination of 30-50 wt.% showed improvement in Tensile Strength (TS), Flexural Strength (FS) and Impact Strength (IS) with the filler mixing up to 5 wt.%. The Taguchi optimization (SN graph) observed the combination with PA addition of 5 wt.%, hybrid fiber addition of 30 wt.%, sliding distance and load of 1500 m, 10 N having lower SWR. Similarly for lower CoF, fly ash of 1 wt.%, fiber of 30 wt.%, sliding distance and load of 500 m and 5 N, respectively, with high SN ratio is the best combination. SEM results showed a decrease in filler content, higher load conditions, higher reinforcement causing more surface deformations in the composites.

Many constraints limit the accuracy level of classification of a face recognition system in smart office automation application, and these limitations make mask face recognition an important research area. In this research, a novel deep learning based Faster R-CNN which integrates with Internet of Things (IoT) to overcome the security issues in the office. The images of existing employees were gathered in a database and these images are pre-processed to train the neural network. Faster R-CNN employs VGG-16 as the foundation of its architecture to extract the features from pre-processed pictures. The recent development in Internet of Things (IoT) and deep learning have made it possible to addressing the difficulties of face recognition with deep neural network. Based on the feature classification, when a member of an organization approaches the door, it instantly opens. The door remains locked if it is an unknown individual. The images of a both authorized and unauthorized person were stored in a cloud and send it to the office manager for monitoring. The proposed Faster R-CNN model attain the accuracy range 99.3% better than the existing system. The proposed Faster R-CNN improves the overall accuracy ranges of 2.06%, 5.63%, 9.36%, and 3.54% better than Deep CNN, SVM, LBPH, and OMTCNN respectively.

In this work, the tribological performance of bidirectional jute/carbon fiber reinforced polyester composites was investigated using response surface methodology. The effects of three factors namely fiber weight fraction, load, and sliding velocity on the wear and friction values were examined. The composites were fabricated by using compression molding technique and the dry sliding test was conducted using pin-on-disk machine. The response surface methodology coupled with three factors – three-level Box-Behnken design was employed to examine the interactive effects of process variables on wear loss and coefficient of friction. Moreover, Analysis of Variance technique was used to inspect the statistical significance of the developed model. The outcomes revealed that the wear loss increased with the increase in sliding velocity and load and decreased with the increase in weight volume fraction due to diminishing contact between the polyester matrix and rotating disk. However, the coefficient of friction decreased with the increase in process variables. Furthermore, the morphology of worn-out samples was examined using scanning electron microscopy to understand wear mechanisms.

This paper reports the morphological, physical, chemical, mechanical and thermal properties of untreated and various chemically treated natural fibers extracted from the petioles of the Phoenix sp. plants. The outcome of morphological analysis revealed that the treated Phoenix sp. fibers have tiny protrusions on its surface which promotes the mechanical interlocking between fiber and matrix. The physical and chemical analysis ensured that the chemical treatments had a positive impact. The chemical functional groups present in the Phoenix sp. fibers were confirmed through FTIR analysis. The improvement in crystallinity index values of treated fibers was confirmed through X-ray diffraction analysis. The fiber treated with acrylic acid exhibited the highest tensile strength and tensile modulus of 466.35 MPa and 9.26 GPa, respectively. The thermal stability of the Phoenix sp. fiber was examined through thermogravimetric analysis and it revealed that the treated fibers have better thermal stability. The above results concluded that the Phoenix sp. fiber is an appropriate reinforcement material for preparing polymer matrix composites.

This paper presents the tribological performance of Phoenix sp. fiber-reinforced tribo-composites based on epoxy. The Phoenix sp. fiber-reinforced epoxy composites were fabricated by varying the fiber length (10, 20, and 30 mm) and fiber volume fraction (10%, 20%, 30%, 40%, and 50%) using the compression molding technique. The dry sliding wear test was conducted using pin-on-disk wear testing machine at different loads (10, 20, and 30 N), sliding speed (1, 2, and 3 m/s), and sliding distance (1, 2, and 3 km). The outcomes revealed that the presence of Phoenix sp. fibers in the composites improved the tribological performance of the neat epoxy. Moreover, the optimal fiber length and the fiber volume fraction were found to be 20 mm and 40%, respectively. The morphology of the worn surfaces of the samples was examined using a scanning electron microscope to study the wear mechanisms.

In this investigation, aluminium-silicon-based alloy (LM6) with the addition of (0, 2.5, 5, and 10%) copper-coated short steel fiber and 5% boron carbide (B4C) element-strengthened composites was fabricated by the stir casting method. Mechanical properties and tribological behaviors of LM6-based hybrid composites were investigated, and microstructures of different castings were examined by an image analyzer. The test was conducted at different loads (10, 20, 30, and 40 N) and different sliding spaces (500, 1000, 1500, and 2000 m), respectively. The results revealed that the sample loaded with 10% of reinforcement recorded the highest tensile strength of 231 MPa. On the other hand, the hardness value increased from 71 to 144 BHN, when 15% of reinforcement was added to the sample. It was also noted that 10% copper-coated steel fiber improved wear resistance up to 50% when compared to LM6. A field emission scanning electron microscope was employed to observe the morphology of the worn surfaces of composites at different sliding distances and load conditions. The hybrid composite revealed that the combination of both short steel fibers and reinforcement of ceramic particles enhanced the mechanical properties, obtaining superior wear resistance.

Nowadays, as environmental awareness is key issue among researchers, scientific community is looking for natural materials as they are biodegradable, low cost, eco-friendly and also safe for health. Researchers and academicians have found many natural fibers and studied their properties for their sustainable applications in various possible sectors, and studies are also going on. So, in that context several natural fiber like jute, sisal, banana, pineapple, flax, hemp, kenaf, bamboo, cornstalk waste, coir, etc. have been successfully utilized as a reinforcing material in polymer composites by replacing man made synthetic fiber. Apart from traditional natural fibers, scientific community is also looking for locally available natural fibers across the globe in different geographical locations for successful reinforcement in polymer matrix. This will not only decrease burden on traditional fibers and but also at the same time it would be helpful to enrich the rural economy. Natural fiber based composites can be used in different areas such as auto motive industry, construction industry, sports industry and food industry. This study is related with extraction, characterization, surface treatment thermal analysis and activation energy of different uncommon natural fibers available at different geographical locations worldwide. The purpose of this study is to provide a comprehensive knowledge on extraction techniques, treatment methodologies, and properties of these uncommon natural fibers so that these novel materials can be utilized efficiently as a reinforcing material in different polymer matrix. Discussions on traditional natural fibers like Bagasse, Wheat straw, Coir, Pineapple, Banana etc. have been compiled extensively in various review papers but compilation on these new uncommon natural fibers is rare. Thermal analysis along with activation energy evaluation is another aspect which has been given emphasis in discussion because this is also a very important examination to evaluate the thermal stability of these natural fibers.