Malaysian Journal on Composites Science and Manufacturing

Work Standardization in Lean Manufacturing for Improvement of Production Line Performance in SME

Md. Shahidul Islam — 2024-03-27

Lean manufacturing is a management philosophy and production system that provides all humanly conceived soft technology to remove waste in any production line. One of the requirements of lean is work standardization. Work standards impose a 'rule of law' in a production line by restricting operators to how long they should work on a single unit. The standards consist of the standard workflow, standard work time, and standard quantity that must be adhered to to meet the customers' demands. The main objectives of this study were to improve the performance of a production line, say SW660 x 600, in terms of weekly output, lead time, and work-in-process (WIP). By applying certain lean elements to the production line, this work indeed improved the performance of the production line. In this work, 5S, PDCA cycle, SPC, and VSM tools were used together to solve the production line problems systematically. It was noticed that the low weekly output and long cycle time at each workstation resulted in delays in the delivery of products to customers. The study managed to increase the weekly output from 61.75 per week to 128.75, an improvement of more than 108.50 percent. Next, in terms of lead time, with the help of a simulation exercise, this work also managed to reduce the lead time from 5 to 1 hour, a reduction of 80 percent. Lastly, the WIP also recorded a reduction from an average of 17 to 9 units weekly, which was an improvement of 47 percent on the weekly WIP. Therefore, this work showed that with the introduction of work standards on the production line, the organization could meet the customers' demands and deliver on time as promised. The study can also be used in other production lines of this and other organizations to help improve their production line performance in the long run.

Fabrication and Analysis of Physico-Mechanical Characteristics of Chemically Treated Bhendi Fiber Reinforced Thermoplastic Composites: Effect of UV Radiation

Haydar Zaman — 2024-03-27

Unidirectional polypropylene (PP) composites reinforced with bhendi fibers (BFs) were produced after BFs were subjected to UV light at different intensities. Mechanical parameters such as tensile strength, tensile modulus, and impact strength of irradiated BF/PP composites significantly improved compared to non-irradiated counterparts. To enhance their properties, different amounts of 2-hydroxyethyl methacrylate (HEMA) in methanol were applied to the surfaces of irradiated BFs, and UV light was subsequently used to cure them. Tensile strength, tensile modulus, and impact strength values rose by 32%, 20%, and 37%, respectively, after the optimized grafting and mechanical properties. Alkali solutions were applied to BFs for 30 minutes at varying temperatures and concentrations to alter their surfaces. Then, using the same UV light, BFs were photocured after being grafted with an optimal HEMA solution. Of all the composite samples treated with 10% HEMA, the alkali + 10% HEMA-treated composites exhibited superior mechanical performance. SEM studies exhibited that the optimized alkali with 10% HEMA treated composite had better dispersion than the 10% HEMA treated composite. Water absorption was significantly lower in the treated than in the untreated sample. According to weather studies, the treated specimens may have less loss tensile characteristics than the untreated specimens.

Thermo-Mechanical, Structural, and Biodegradability Properties of Water Hyacinth and Sheep Wool Fiber Reinforced Hybrid Polypropylene Composites

Md. Fahim Faisal Chowdhury — 2024-03-27

Hybrid fiber reinforcements can incorporate a wider array of qualities than single fiber reinforcement. Instead of synthetic fibers, applying plant and animal-based organic materials as reinforcement in polymer matrix offers certain benefits, such as low price, greater availability, and better biodegradability. In the present study, water hyacinth fiber and sheep wool fiber reinforced polypropylene hybrid composites were fabricated at three different (5, 10, and 15 wt.%) fiber loading. The effect of fiber loading on thermo-mechanical, structural, and biodegradability properties was subsequently investigated. The manufacturing process of the composite material was carried out with utmost consideration for biodegradability, since polypropylene, the primary constituent, is not inherently biodegradable. The insertion of fibers into the polypropylene matrix showed variance in properties of different aspects. The tensile strength of the composites displayed a downward trajectory (from 25 to 10 MPa) with a 15% increase in fiber loading due to voids, and fiber dispersion, while impact strength exhibited an opposite trend (from 25 to 32 J/m). Except for hardness, all the mechanical properties degraded slightly after the employment of the reinforcement. Fourier transform infrared spectroscopic analysis revealed the movement of typical peaks and the appearance of new peaks demonstrating the bonding between the fiber and the matrix. Thermogravimetric analysis showed that the thermal degradation temperature of the composites improved at maximum fiber loading. On the other hand, the goal of achieving biodegradability has been succeeded by the implementation of a combination of plant and animal-based fibers as biodegradability of the manufactured composites thrives with increasing fiber content for the presence of cellulosic bonds, as evident from the FTIR spectrum. Even though some properties of the hybrid composite declined slightly with increasing fiber loading, the other characteristics, including service temperature and biodegradability experienced a prospective advancement. Hence, the 15% fiber-loaded composite was found to be a potential candidate in terms of slightly high temperature and environment-friendly applications.

Corrosion Resistance of Scraped Copper in Velocity Varied Inland Water of Bangladesh

M Muzibur Rahman — 2024-03-27

Copper (Cu) is widely used for electrical wires, equipment parts, and components in commercial, industrial, and marine fields due to its excellent electromechanical properties. With rapid scientific and technological advancement and economic development, the demand for copper is increasing continuously. As such, scraped items have become important to meet the rising demand considering the depletion level of copper ores in nature. But sometimes old copper contains tin (Sn), lead (Pb), etc., which may alter its properties. Thus, it is necessary to characterize different properties, including corrosion resistance, to explore the appropriate engineering applications of scraped copper waste items. In this context, the present research reports the study of the corrosion behavior of pure Cu and scraped Cu in the river water environment of Bangladesh for the submersed period of 36 days. The investigations have been carried out for three relative velocity conditions of fluid, i.e., 0, 2 and 4 m/s. A gravimetric analysis was done to find out the corrosion rate. The results of this study indicate that the presence of only 1%Sn and 1%Pb in copper has significantly increased the corrosion rate in all three velocity conditions. At the same time, scraped copper's average corrosion rate has been increased by about 10% while the relative velocity is changed from 0 to 4 m/s. Micrographs have confirmed the extent of corrosion severity resulting from chemical composition and fluid velocity alterations.

Effect of Fiber Content on the Mechanical Properties of Jute Fiber Reinforced Perlite/Gypsum Composites

Pranto Karua — 2024-03-27

Fiber reinforcement is one of the ways for the improvement of the mechanical properties of composite materials. Previously, it was seen that the fiber content in composites played a vital role in the mechanical properties of fiber-reinforced composites. Considering the benefits of natural fiber, in this work, jute fiber reinforced perlite/gypsum composites were manufactured with five different fiber contents ranging from 2.41 % to 4.82 %. The ratios of gypsum to perlite and gypsum to water were kept constant, and only fiber content was varied. The compression and flexural tests were conducted to investigate the effect of jute fiber content on the mechanical properties of jute fiber-reinforced perlite/gypsum composites. Results showed that both the compressive and flexural properties were improved up to certain jute fiber content. The compressive strength, modulus, and energy absorption of the jute fiber-reinforced composite were found to be the maximum at 3.01 % fiber content. The compressive strength of the composite with 3.01 % jute fiber content was 35.23 % higher than the composite with 2.41 % fiber content. The flexural strength, modulus, and energy absorption were maximum at 3.61 % jute fiber content. This study demonstrated that the addition of jute fiber to perlite/gypsum composites results in improved mechanical properties up to a certain percentage of jute fiber, beyond which the properties deteriorate.

Effect of Fiber Orientation and Volume Fraction on Young's Modulus for Unidirectional Carbon Fiber Reinforced Composites: A Numerical Investigation

Md Sakhawat Hossain — 2024-03-27

The modulus of elasticity of unidirectional fiber-reinforced composites greatly depends on the fiber orientation and the fiber volume fraction. This paper investigates the effects of fiber orientation and fiber volume fraction using the commercially available Finite Element Analysis (FEA) software Abaqus. Carbon fiber is the reinforcing material, while epoxy is used as the matrix. Representative Volume Element (RVE) of the unidirectional carbon fiber reinforced composites are modeled in Abaqus, and the unidirectional tensile test is simulated to determine the modulus of elasticity for different fiber orientations and fiber volume fractions. The numerical results are verified by previously published results and by experimental results. It is found that the modulus of elasticity of the composite is maximum when the fiber inclination angle is 0°, i.e., the fibers are placed along the loading direction. As the fiber orientation angle increases, the modulus of elasticity also decreases and is almost constant after 45°. A linear increase in modulus of elasticity is observed for an increase in fiber volume fraction. This model will help the researcher to select the appropriate fiber orientation and volume fraction for a specific application.

An Innovative Approach to Assess the Potentiality of Using Activated Carbon and Rice Husk Ash in Aluminum-Air Battery

Md. Anayet Ullah Patwari — 2024-03-27

Aluminum-air (Al-air) cells have the potential to become vital in energy storage applications in the future because of their high energy density, which is even higher than that of commonly used lithium-ion batteries. However, it is not used widely because the cost of air cathode catalysts and metal anode is high. However, suppose the catalysts are replaced with activated carbon or rice husk ash as an alternative and recycled aluminum foil as an anode. In that case, the production cost might be feasible for the vast use of this type of cell. This study's main objective is to utilize some commonly available material in fabricating an Al-air battery suitable for small and day-to-day usage, reducing production costs and limitations. In this paper, a focused analysis was made on the feasibility of using an activated carbon and rice husk mixture as an air cathode catalyst for an Al-air cell, and the observations were interesting. About 11 samples of a mixture of rice husk ash (RHA) and activated carbon (AC) in different ratios have been made to find the best results from 0.68-0.72 V, which increases by 8-20%, measuring each sample after 3 days. In this study, another attempt was made to replace the graphite cathode of a dry cell with a mixture of AC and RHA. Voltage drop is quite negligible for the mixture of 10% RHA. The resulting voltage is similar to the new 100% activated carbon battery as a cathode. If considering the environmental effect, using recycled activated carbon and rice husk ash will decrease pollution and open a new door to apply in primary cells.

Effect of Adhesive Type on the Adhesively Bonded Stepped Joint: A Numerical Investigation

Md Sayed Anwar — 2024-03-27

Single-lap joints are by far the most widely used adhesive joints and have been the subject of considerable research over the years. It is used in the automobile and aerospace industry where bolted or riveted joints are impossible. The joint strength in adhesively bonded joints depends on the adhesive and adherend properties and adherend geometry. In this paper, both the adhesive property and adherend geometry are considered. Two types of adhesives, i.e., SBT9244 (flexible) and DP460 (stiff), and three types of adherend geometry, Single Lap Joint (SLJ), One Step Lap Joint (OSLJ), and Three Step Lap Joint (TSLJ) are considered, and the effect of these are investigated by using a commercially available software Abaqus. The maximum peel stress occurs in a lap joint towards the edges of the joint and is minimum around the center region. The maximum peel stress is responsible for the failure of the joints, and the objective of this research was to reduce the peel stress, i.e., provide a more uniform stress distribution. Soft adhesive maximum peel stress and shear stress occur in [Type-I] 8.6 MPa and 6.4 MPa, respectively. Similarly, stiff adhesive maximum peel stress and shear stress occur in [Type-I] 37.14 MPa and 20.44 MPa, respectively. It is found from this investigation that if a relatively soft adhesive (SBT9244) is used in the joint, then the stress distribution reduces compared to a stiff adhesive (DP460). On the other hand, if steps are introduced in the bonded region, the stress distribution becomes more uniform and increases the bond strength.

Design, Simulation and Fabrication of an Ergonomic Handgrip for Public Transport in Bangladesh

Afrida Kabir — 2024-03-27

Many individuals in Bangladesh prefer using private vehicles to avoid the discomfort of public transportation, causing significant congestion during rush hours. To ensure a pleasant journey in public transit, including safe and comfortable handgrips becomes crucial. This study adopts a comprehensive approach to alleviate the discomfort and hand fatigue experienced by public transport commuters in Bangladesh. Our research methodology thoroughly analyses existing handgrips with a diverse age group (11-50) and varied occupational backgrounds, ensuring inclusivity. Meticulously collected anthropometric data from previously published works incorporates the 95^th percentiles to account for diverse hand sizes. Leveraging computer-aided design tools, we optimize the hand grip design based on ergonomic principles and hand anatomy. Our study fills a crucial gap by integrating locally derived anthropometric data. The resulting ergonomic hand grip, designed for the specific needs of Bangladeshi commuters, is poised for seamless integration into the public transport system, promising a substantial improvement in comfort and a more positive commuting experience.

The Physicomechanical and Interfacial Properties of the Vetiveria Zizanioides Fiber Reinforced Polymer Composites

Haydar Zaman — 2024-03-27

The effects of chemical treatment and vetiveria zizanioides (vetiver) loading on the physicomechanical, morphological, and weather tests of the vetiver fiber (VF)-filled polypropylene (PP) composites were investigated. Raw VF was chemically treated with sodium dodecyl sulfate (SDS) and SDS-pretreated benzoyl chloride to increase its compatibility with the PP matrix. The mechanical properties of the PP/VF composites, including tensile strength, tensile modulus, impact strength, hardness, and water absorption, were increased by raising the fiber content to the optimum level of 30 wt%. The resultant composites' mechanical characteristics and water desorption were improved by adding SDS and SDS-pretreated benzoyl chloride for the VF. PP/VF composites containing benzoyl chloride after SDS pretreatment show better mechanical performance when compared to untreated and SDS-treated fiber composites. SEM studies showed that the treatment of the fibers enhanced the interfacial interaction between PP and VF, verifying the mechanical properties of the composites. Water absorption tests revealed that SDS-pretreated benzoyl chloride composites absorbed less water than untreated counterparts and even SDS-treated composites. Sodium dodecyl sulfate-pretreated benzoyl chloride composites exhibited less loss in tensile strength and tensile modulus during weather testing than sodium dodecyl sulfate-treated and untreated composites.

Synthesis of Hybrid Composites from Bio-Based Fillers: Chicken Feather, Groundnut Shell, Sawdust

Farhana Afroz — 2024-03-27

Experimental research has investigated the mechanical characteristics and water absorption performance of polyethylene-based composites reinforced with sawdust, chicken feathers and groundnut shells. Composite samples have been produced with preset volumetric ratios (20%, 30%, 40%, and 50%) at 160°C and 25 kN pressure. A compression molding machine was used to produce specimens of composite materials. The findings indicate that the composites exhibit promising mechanical properties, making them potentially suitable for various applications. However, the waste polyethylene sheet was tested for comparison. It displayed a tensile strength of 7.56 MPa, impact strength with an average energy absorption of 0.093 J, and hardness strength with an average energy value of 92.72 J. The water absorbency data showed minimal water absorption for composite samples, indicating their resistance to water penetration. Similarly, the thickness swelling data revealed no significant change in thickness after immersion, demonstrating dimensional stability in the presence of moisture. This article presents the details of these experiments conducted systematically.