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AbstractIn recent years, adhesive bonding has increasingly been used in many applications as it has many advantages over traditional joining techniques. More uniform stress distribution, absence of damage in the adhesive-bonded parts, high fatigue resistance, ease of manufacture, capability of fluid sealing, and the possibility of joining dissimilar materials are the advantages of adhesive bonding. This paper reviews the current research, advancements in adhesively bonded single lap joints (SLJs) and the related issues for joining different materials. The influence of various factors such as loading direction joint geometry, type of adhesive, type of adherend, joining technique, surface preparation technique, and environmental conditions on the bond properties of the adhesively bonded joints are also discussed. Different failure mechanisms associated with adhesive bonding are also highlighted. The geometry and method of manufacturing, surface preparation, and curing conditions significantly influence the strength of adhesively bonded joints. The combined surface treatment substantially affects the mode of failure in the adhesive joints. Among the different numerical methods, the cohesive zone modelling (CZM) approach can forecast the adhesive strength of joints for a wide range of designs with minimal error. Advanced numerical methodologies, such as the eXtended finite element method (XFEM) or meshless methods, have been utilized for adhesive joint analysis; however, further enhancements are requisite for their broader adoption. [ABSTRACT FROM AUTHOR]

In this study, calcium carbonate (CaCO3) nanoparticles were added to basalt fiber reinforced epoxy (BFRP) composites in varied weight fractions to examine their effects on the materials' mechanical, thermal, and physical properties. Through magnetic stirring and sonication, the epoxy matrix was altered with various weight fractions of CaCO3 nanoparticles (0%, 0.5%, 0.7%, 1%, and 1.5%). It has been found that adding 1 wt% of nanoparticles to the matrix produced the greatest results in terms of tensile, flexural, impact, and inter‐laminar shear strength (ILSS). With 1.5 wt% of nano CaCO3 in the composites, the best results for the micro‐hardness and glass transition temperature were obtained. The diffraction peaks of the nanocomposites have been identified using XRD investigation. Scanning electron microscopy (SEM) analyses has been done on the fracture surfaces of the nanocomposites to analyze the influence of the nanoparticles on the interfacial adhesion of fiber and the matrix. [ABSTRACT FROM AUTHOR]

Nowadays, the search for natural filler to be substituted for synthetic filler providing renewability, eco-friendly, low cost and nontoxic have prompted the researcher to suggest new natural filler reinforced composite materials for structural and automotive application. The bast fibers like sisal, jute, hemp, ramie and flax have already been studied as reinforcements to the polymer composites with enhanced mechanical, thermal and flammability properties. The present study was intended to examine extensively the characteristics of the novel Sirisha bark filler as an alternate novel filler to the polymer composites. The density of the bark filler was found to be 0.713 g/cc. The cellulose, hemicellulose, lignin, moisture and ash content of the filler were found to be 68.23%, 13.26%, 13.25%, 12.66% and 1.82% respectively in comparison to other bark filler. The crystallinity index was calculated to be 65.71% from the X-Ray Diffraction (XRD) analysis. The Thermogravimetric analysis (TGA) study revealed the thermal stability of the Sirisha bark filler to the temperature of 429°C with activation energy of 54.5 kJ/mol. The trace elements like Ca, Al were found to be 1.30% and 2.54% from Energy-dispersive X-ray spectroscopy (EDX). [ABSTRACT FROM AUTHOR]

Recently, the natural fibers replaced the synthetic fibers to a great extent as reinforcement to the polymer composites. Among the natural fibers, coir fibers has the potential to be used in various applications because of its abundancy, non-toxicity, low cost, and resilient properties. Generally, the polymeric materials are very sensitive to the flame. That is why it is inevitable to measure the performance of the polymer composites prior to the applications such as construction, automotive parts, etc. Coir fibers have high lignin content that makes it a preferable reinforcement in the development of polymer composites to enhance the fire resistant properties. The aim of this work is to study the flammability properties of coir fibers reinforced polypropylene composites along with the thermal stability and mechanical properties. Composites were fabricated by melt compounding with micro-compounder followed by compression molding. The dynamic mechanical properties were analyzed. The storage modulus of coir/polypropylene composites was found to be increased than the neat polypropylene but the damping properties of the composites were decreased. The flammability properties have been studied using horizontal burning test by UL-94. It is observed from the study that the composites with 30 wt% of coir fibers content achieved V-0 rating. The flame propagation speed increased for composites up to 20 wt% of coir fibers content and after that it was decreased. The thermal stability of the composites was found to be increased with the increase in fiber loading. [ABSTRACT FROM AUTHOR]

Nowadays, the demand for needle-punched nonwoven fabrics has been increasing, especially in the areas of high-performance composites as reinforcement due to their potential of imparting high z -directional strength, easy resin absorption, light weight, and low cost. In this study, needle-punched nonwoven viscose fabric-reinforced epoxy composites are prepared by varying the area density of fabric mat (100 gsm, 200 gsm, 300 gsm, and 400 gsm) at constant fabric loading of 30 wt.%. The effects of area density on mechanical and slurry abrasion behavior of composites are studied under controlled laboratory conditions. It is observed that the mechanical properties and abrasive wear resistance under steady-state condition has been improved with the increase in area density of fabric mat. Furthermore, experimental design through Taguchi's L 1 6 orthogonal array is applied to find out the optimal parametric combination for minimum wear rate. It is also observed through the analysis that silica sand size and sliding velocity are the most influential factors for wear rate. [ABSTRACT FROM AUTHOR]

Byline: Sandhyarani Biswas, S.S. Mahapatra Production planning in Flexible Manufacturing Systems (FMSs) requires several hierarchical issues to be resolved sequentially or simultaneously. Loading is one of the vital issues in FMS production planning. It deals with the assignment of the necessary operations and tools among various machines in an optimal manner to minimise system unbalance under technological constraints. Such a problem is combinatorial in nature and found to be NP-complete; thus, finding the exact solutions is computationally intractable for large-scale problems. Therefore, in this study, a metaheuristic approach based on Particle Swarm Optimisation (PSO) has been proposed to solve the machine loading problem. Mutation has been introduced in PSO in a novel way so that the trapping of solutions at local minima can be avoided. The comparative study of the proposed algorithm with existing methods for ten benchmark instances available in the literature suggests that the results obtained in the proposed algorithm are quite encouraging.