Compression Moulding Process Research Articles

The effects of manufacturing processes on the physical and mechanical properties of basalt fibre reinforced polybenzoxazine

The present work provides a comparative investigation between different methods of manufacturing basalt fibre reinforced polybenzoxazines (BFRP), including vacuum infusion, hand laminating, dynamic fluid compression moulding and autoclave curing processes. In comparison to the high pressure based autoclave-cured and compression-moulded BFRPs, vacuum-infused BFRPs showed similar or even higher mechanical properties. Despite the low pressure curing, vacuum infusion yielded BFRPs with a 10% higher tensile strength and a 24% higher strain at failure compared to its autoclave-cured counterparts. Thus, it is possible to gain BFRPs with near-zero porosity and high mechanical properties without the need of high pressure curing methods.

Optimization of Flexural Strength of Recycled Polyethylene-terephthalate (PET) Eco-Composite using Response Surface Methodology

Recycling and reuse of plastic waste by blending with virgin polymer has been affirmed to be the best way of managing the waste. Equally, agro-waste are best recycled than being burnt off. In the development of stronger and cheaper ecoefficient recycled PET composite for food packaging, this study focused on reinforcement of the blend of 20 wt. % recycled PET (rPET) and 80 wt. % virgin PET (vPET) with snail shell particulate and kenaf fiber via compression moulding process. The process parameters are fiber dosage, particulate dosage, moulding pressure and temperature. Box-Behnken design was engaged in the design of experiment and the samples were produced according to the experimental runs. Result of analysis of variance pinpointed the process factors as significant contributors to the flexural strength response. The model developed was validated to be significant and statistically fit. Interactions between the process variables as revealed by the response surface plots indicated the response was dependent on the interactive pattern between the variables. Response surface optimization showed an optimum flexural strength of 57.16 MPa was attainable at process parameters of 27.27 wt. %, 4.18 wt. %, 3.95 MPa, and 160 ˚C for fiber proportion, particulate proportion, moulding pressure and temperature respectively yielding 34.2 % improvement over the reference 80/20-vPET/rPET matrix. Model validation experiment undergone with the combined parameters and deviation of +0.036 was noted. Since the deviation is insignificant, the model is concluded to be statistically fit for predicting the flexural strength of the developed eco-composite.

Fiber extraction and mechanical properties of Agave Americana/Kenaf fiber reinforced hybrid epoxy composite

The present work investigates the fiber extraction, tensile and flexural properties of agave American/kenaf fibers reinforced epoxy Hybrid composites. The fibers length are varied from 1 cm to 4 cm with varying the relative fiber weight fraction (Wf) such as 10, 15, 20 and 25% respectively. Fibers were extracted manually by water retting process. The random mixed fibers reinforced hybrid composites were prepared by handy layup method with compression moulding process. Scanning Electron Microscopy was employed for studying the microstructure of the specimen. Specimens were cut and tested by following ASTM standard. The experimental analysis has shown that fiber length of 3 cm having 20% Wf yields the best results for tensile and flexural strength.

Evaluation of Mechanical Properties of Sisal and Bamboo Fibres Reinforced with Polymer Matrix Composites Prepared by Compression Moulding Process

Today’s modern, dynamic world would be impossible to imagine without the concept of composite material advancement. Various studies are being conducted in this area in order to reach the desired level. In terms of compatibility, natural fibre reinforced polymer‐based composites and synthetic fibre composites are very similar. Because they are lightweight, nontoxic, and nonabrasive, they are very popular with consumers. They are also readily available and affordable. Composite materials made from natural fibre have superior mechanical properties compared to those made from synthetic fibre. As part of this research, an epoxy‐based composite with bamboo and sisal fibre reinforcement is examined. Reinforced with epoxy resin, bamboo fibre and sisal fibre are used to make composite materials. The effect of adding bamboo fibre and sisal fibre in various weight percentages on the mechanical behaviour of composites is investigated.

SPARE project – improvement of continuous compression moulding process for the production of thermoplastic composite beams

In recent years, thermoplastic matrix composites have seen an increasing interest from the research and development sector due to the versatility of use and the wide potential in sectors such as automotive, aeronautics and transport. Furthermore, the thermoplastic matrix allows the use of simpler, faster and automatable production cycles and joining systems. As part of the SPARE project, the continuous compression moulding process (CCM) was upgraded using as numerical simulation, monitoring via infrared thermography and induction welding. Thanks to these innovations, the CCM process can ensure savings in terms of production costs, reduction of waste and a higher level of automation, the proposed work will illustrate the activities carried out during the project. The numerical simulation was used to analyze the heating process and verify its uniformity in order to identify the best configuration to obtain uniform heating, infrared thermography, on the other hand, was used to continuously monitor the temperate of the laminate at the entrance and exit of the compaction zone and to measure the process temperature and the degree of uniformity.Finally, at the end of the production process, a tool was developed for the induction welding of the laminates for the construction of complex beams with a T or H cross section.

Mechanical Characterization and Evaluation of NaOH Treated Chopped Abaca Fiber Reinforced Epoxy Composites

Researchers have been busy developing new environmental friendly products and materials based on sustainability principles to reduce pollution and prevention of our resourceful non-biodegradable and non-renewable sources. Over synthetic materials there are many unquestionable focal points for natural fibers and some of them are low thickness, least waste transfer issues and also equivalent quality. In this research the mechanical properties of abaca fiber reinforced epoxy composite were evaluated. Then with the help of compression moulding process, different composite samples of varying fiber volume fractions were prepared. Different mechanical tests such as tensile, flexural, impact and hardness were conducted on the prepared samples. 25 wt% of abaca fibre volume fraction composites shows better mechanical properties.

Determination and investigation of mechanical behaviour on kenaf-sisal hybrid composite

Technological development in automobile & aerospace industries make us to develop new materials that have high strength to weight ratio, good mechanical characteristics and better corrosion resistance. Composite materials fulfill the above requirements. In this project, hybrid composites are fabricated in which natural fiber is used as a reinforcement and the epoxy resin along with hardener & Graphene are used as a matrix. Kenaf and Sisal fiber are used for fabricating the hybrid composite. Compression moulding process is used for fabricating the composites in which machine is maintained at 120 degree celsius as curing temperature and pressure for 10 bar for 2–3 h. Three Samples such as (kenaf - kenaf), (sisal - sisal), (kenaf - sisal) combinations were fabricated namely composite 1, composite 2, and composite 3 respectively. Testing such as tensile, flexural, impact and wear are performed on three composites. It is found that composite 3 has better mechanical behavior as compared to other composites as Tensile strength of 156 Mpa, and Flexural strength of 282 Mpa. Impact test value remains same for all the composites. Micro-structural analysis was performed by using scanning electron microscope to explain the failure mechanisms and behaviour of the composites

Spectroscopic Study of Ultra High Molecular Weight Polyethylene (UHMWPE) and Mg-Ni-doped ZnFe<SUB>2</SUB>O<SUB>3</SUB> Nano Composites

The present study aims at investigating the effect of incorporating nano scale MgxNixZn1-xFe2O3 (where x=0.15) as nano fillers on the physical and chemical stability of ultra high molecular weight polyethylene (UHMWPE). The effect of adding 1% and 2% (by weight) nano fillers on the physicochemical properties of UHMWPE/MgxNixZn1-xFe2O3 nano composites have also been investigated by using FTIR, Raman, and UV-VIS spectroscopy. FTIR data of UHMWPE/MgxNixZn1-xFe2O3 nano composites reveal that the addition of MgxNixZn1-xFe2O3 up to 1% induces significant chemical and physical structural alterations in UHMWPE matrix. However, this behavior is found to reduce on increasing the concentration of nano fillers from 1% to 2%. Raman spectroscopic data shows that crystalline contents of UHMWPE remain unaffected with the addition of nano fillers, however; a significant increase in amorphous contents and decrease in all-trans interphase region is observed. This behavior is attributed to the chain scission reactions due to addition of MgxNixZn1-xFe2O3 followed by compression moulding process at high pressure and elevated temperature. Absorption spectroscopy analysis revealed that the incorporation of MgxNixZn1-xFe2O3 results in decrease of energy band gaps from 2.14 eV to 2.08 eV (for direct transition) and from 1.54 eV to 1.38eV (for indirect transition) due to band gap energy which is induced because of MgxNixZn1-xFe2O3 incorporation as nano fillers within the PE matrix.

Synthesis and characterization of natural fiber reinforced laminated thermoplastic composite

As increase in the use of eco-friendly, natural fibers are used for the reinforcement of polymer composites which has the light weight and low-cost polymer composites with better mechanical properties which offers exceptional properties over glass fiber. In this work, Basalt fiber reinforced Polypropylene (PP) laminated composite was manufactured by the compression moulding process. The variations of impact, flexural and compression strength and modules of the composite according to the number of basalt fiber layers were investigated. Scanning electron microscopy (SEM) and Energy-dispersive X-ray (EDX) conducted on the surface of the composite reveal the superior interfacial linkage between the basalt fiber and PP matrix. Hence, this offers a comprehensive discussion on synthesis and characterization of basalt fiber with polypropylene reinforced laminated thermoplastic composite.

Experimental assessment of low velocity impact damage in flax fabrics reinforced biocomposites by coupled high-speed imaging and DIC analysis

Structural composite materials with good impact resistance are required in several industrial sectors to design parts submitted to crashes or falling objects. This work investigates the impact behaviour of flax fabrics-epoxy and commingled flax-polypropylene (PP) fibres composite plates manufactured using compression moulding process. An instrumented drop tower was used to conduct low velocity impact tests at several energies and high-speed imaging coupled with DIC analysis was used to assess the damage evolution. A crack-tracking algorithm was implemented in ImageJ to identify the initiation and propagation of cracks. A comparison of the force-displacement histories and high-speed camera results for both composites were used to identify the different modes of damage and the critical energy for complete penetration. The proposed method is able to depict the successive events that lead to the breakage of biocomposites and it will be a valuable tool to investigate the impact behaviour of other materials as well.

Flammability Characteristics and Mechanical Properties of Casein Based Polymeric Composites.

Even though casein has an intrinsic potential ability to act as a flame retardant (FR) additive, the research regarding the FR performance of casein filled polymeric composites has not been thoroughly conducted. In the present work, two commercial casein products, such as lactic casein 720 (LAC) and sodium casein 180 (SC), were chosen to investigate their effects on the performances of the polypropylene (PP) composites. The melt compounding and compression moulding processes were employed to fabricate these casein-based composites. Ammonium polyphosphate (APP) was also selected to explore its combined effects in conjunction with casein on the composite’s flammability. The cone calorimeter results showed that the addition of casein significantly reduced (66%) the peak heat release rate (PHRR) of the composite compared to that of neat PP. In particular, the combination of LAC and APP led to the formation of more compact and rigid char compared to that for SC based sample; hence, a further reduction (80%) in PHRR and self-extinguishment under a vertical burn test were accomplished. Moreover, the tensile modulus of the composite improved (23%) by the combined effects of LAC and APP. The overall research outcome has established the potential of casein as a natural protein FR reducing a polymer’s flammability.

Time-dependent degradation behaviour of phosphate glass fibre reinforced composites with different fibre architecture

In this study, biodegradable Polylactic acid (PLA) composites reinforced with phosphate glass fibres (PGF) using different fibre architecture (UUU, CCC, UCU and CUC) were prepared via compression moulding process. The maximum initial flexural strength and modulus were observed for unidirectional (UD) fibre reinforced composites (UUU), whereas CCC composites with thoroughly chopped fibre reinforcement exhibited the lowest values. The sandwich structure of UCU composite with 50% UD reinforcement in the skin and 50% chopped fibre in core exhibited similar flexural properties in comparison to UUU composites, meeting the flexural property requirements of cortical bone. Furthermore, the degradation behaviour and mechanical performance of composites with different fibre architecture were analysed during the degradation process for 28 days. The UUU composites showed the most rapid degradation of the flexural performance. Meanwhile, a lower reduction of flexural properties was observed for UCU composites due to less susceptibility to wicking in discontinuous fibres. As such, the UCU composite could provide near flexural performance with better retention of properties during the degradation.

Effect of no-pressure curing temperature on bending property of 2D-T700/E44 composite

Carbon-fiber-reinforced polymer (CFRP) composites have received extensive attention in aerospace, weapon equipment, communication electronics, transportation and other fields. The improved compression-molding process is one of the most advantageous processes for preparing CFRP composites. It is important to understand the effects of molding process parameters, in particular temperature parameters, on the preparation of an ideal composite. This paper addresses the effect of the no-pressure curing temperature on the two-dimensional woven CFRP (2D-CFRP) bending property of the improved compression-molding process. 2D-T700/E44 composites were prepared under no-pressure curing temperatures of 80, 90, 100, 110, 120 and 130°C. The effect law and influence mechanism of the temperature parameter on the microstructure and bending property of composites were summarized. The results show that excessively high or low no-pressure curing temperatures are unfavorable for the preparation of 2D-T700/E44 composites. When the temperature is 110°C, the impregnation effect of the resin is ideal, and the defects are effectively controlled. The fracture morphology is reasonable, and the performance is greatly improved, so the bending strength reaches 860 MPa.

Study of ageing effect on mechanical properties of prosopis juliflora fibre reinforced palm seed powder filled polymer composite

ABSTRACT In this work, the natural fibres are reinforced into synthetic fibres along with natural fillers. The fibres are extracted from prosopis juliflora plant barks. The juliflora plants consumes ground water, making the land unusable for cultivation purposes. Then the filler material is obtained by powdering the palm kernel seeds. The palm seeds are collected from the palm trees and by drying it become harder and it was made into powder. The powder is then sieved and separated by their sizes. Both the prosopis juliflora (PS) fibres and the palm seed powder are embedded into the epoxy matrix through compression moulding process and the composite was subjected to ageing, as per the standards and conducted mechanical testing under equal intervals. As reinforcement and the fillers are bio degradable materials, ageing analysis determines the characteristics of the composite in the due course of time. The results showed, mechanical properties can be obtained by adding 30 wt% of PS fibres treated with silane and the addition of the palm kernel seed powders afftect the hardness of the composites to some extent. As the hardness and the water resistance are better, this composite can be used in Automobile and light roofing applications.

Development of innovative flow visualisation methods to investigate the stages of Wet Compression Moulding (WCM) process

The WCM is a novel production technique for fibre-reinforced polymer components. This technique is increasingly adopted in industry, typically in the automotive sector for medium to large-scale production. This process reduces the cost per part significantly by reducing the number of tools and processing steps, relative to Resin Transfer Moulding. To date, the processing variables, their relations and effect on the composite quality have been established through the knowledge gained by technologists. The drive of this research is to develop a fundamental understanding of the impact of process parameters (key process timings and cavity thicknesses, mould closing speed, edge clamping frame dimensions) and material properties (fibre reinforcement compaction response, permeability, and wettability together with test fluid viscosity and surface tension) on textile wetting, impregnation, and resulting composite part quality. In this study, a 480g/m2 non-crimp unidirectional glass fibre reinforcement has been chosen and characterised for compaction response, in-plane, and through-thickness permeability. For ease of handling, motor oil (DTE heavy VG100) has been characterised and used as a test fluid. Two experimental flow visualisation setups have been developed at the CACM to investigate the influence of process and material parameters on initial resin application and textile wetting, and the subsequent compression flow stage.

Effects of High-Temperature Exposure on the Mechanical Properties of Kenaf Composites

Automotive parts, including dashboards and trunk covers, are now fabricated through a compression-molding process in order to produce lightweight products and optimize fuel consumption. However, their mechanical strength is not compromised to avoid safety issues. Therefore, this study investigates kenaf-fiber-reinforced polypropylene composites using a simple combing approach to unidirectionally align kenaf fibers at 0°. The kenaf composite was found to withstand a maximal temperature of 120 °C. The tensile and flexural strengths of the aligned kenaf composites (50 and 90 MPa, respectively) were three times higher than those of the commercialized Product T (between 39 and 30.5 MPa, respectively) at a temperature range of 90 to 120 °C. These findings clearly showed that the mechanical properties of aligned kenaf fibers fabricated through the combing technique were able to withstand high operating temperatures (120 °C), and could be used as an alternative to other commercial natural-fiber products.

Superhydrophobic silicone rubber surface prepared by direct replication

ABSTRACT The superhydrophobic surface of silicone rubber was prepared by means of a simple direct replication and compression moulding process. It was worth noting that the rough structure endowed the surface of the silicone rubber with excellent superhydrophobic, low adhesion and self-cleaning properties. The contact angle with water was 158.5 ± 0.5°, and the rolling angle was 8.9 ± 0.1°. Even if immersed in water, the surface will not become wetted by the water. In addition, it has excellent properties of hydrophobic hydrochloric acid solution, sodium hydroxide solution and sodium chloride solution. Through a high-speed camera, it was found that water droplets would bounce up after falling on the superhydrophobic surface of the silicone rubber. When the liquid drops fall perpendicular to the superhydrophobic surface of silicone rubber, the time of contact between the liquid drops and the superhydrophobic surface is not inversely proportional to the height of the drop falling.

Optimizing various parameters influencing mechanical properties of banana/coir natural fiber composites using grey relational analysis and artificial neural network models

The natural fibers of banana and coir from southern part of India was taken as the reinforcement material. Taguchi-based grey relational analysis was used for optimizing the factors influencing tensile, flexural and impact strength of banana/coir composites. Banana wt%, coir wt%, alkali treatment %, pressure and temperature during compression moulding process were the five major factors used for optimizing the mechanical strengths of epoxy-based composites. Grey relational analysis observed 20% banana/15% coir/3% alkali treatment/16 MPa pressure and 100°C temperature combination having the maximum mechanical properties in 16 trial combinations. The signal-to-noise ratio table of grey relational analysis showed combination with 20% banana /15% coir/5% alkali treatment/16 MPa pressure and 100°C temperature having optimized mechanical properties. Banana has the highest rank in improving the mechanical strength of natural composites, followed by coir, alkali treatment %, pressure and temperature. The graph between actual and artificial neural network computed results observed high correlation, proving that network topology of 5-3-1 with five factors, three hidden nodes and one response is the best method for analyzing the parameters in mechanical strength. Hybrid fiber composites with NaOH treatment showed hackles in interface with improved interfacial bonding during SEM analysis.

Study on Mechanical, Thermal and Morphological Properties of Banana Fiber-Reinforced Epoxy Composites

In recent decades, engineering applications involving polymer composites reinforced with natural fibers have increased significantly due to the advantages not only of favorable composite properties but also of fiber durability and environmental friendly nature. In the present work composites reinforced with upto 20 wt% fabric made of banana, a relatively known natural fiber from India. These banana fibers were cut into a similar average length of 10 and 20 mm and two sets of bio-composites were prepared by compression moulding process with varying weight percentage of epoxy resin by 0, 5, 10, 15 and 20%. Experimental results showed tensile, flexural and impact strength of bio-composites with up to 15 wt% has increased compared with neat epoxy. However, the mechanical strength has decreased above 15 wt% fiber reinforcement. This is a study of thermogravimetric analysis (TGA) that banana fiber-reinforced composites have high thermal stability up to 220 oC.

Physical, mechanical and thermal properties of high frequency microwave treated plantain (Musa Paradisiaca) fibre/MWCNT hybrid epoxy nanocomposites

Natural fibre reinforced polymer composite has many industrial applications especially in automobile. However low mechanical and thermal property has limited its application. In this study, natural fibre reinforced hybrid nanocomposite was manufactured by the incorporation of high frequency microwave treated Plantain (Musa paradisiaca) fibre and multiwalled carbon nanotubes (MWCNT) using a single epoxy resin matrix. The consequence of harmonized existence of MWCNT at different loading (0.5−2wt.%) on the physical, mechanical and thermal Properties of the hybrid nanocomposite was examined, using the ultrasonic technique for dispersion of nanoparticles and hand lay-up and compression moulding process for composite production. The experimental results demonstrate that the mechanical properties strength improve up to 52%, while up to 30% improvement was recorded for micro-hardness and impact strength, caused by increment in MWCNT content. Scanning electron microscope (SEM) analysis reveals good mechanical dovetailing of hybrid fibres with polymer matrix. Thermal conductivity has shown significant improvement up to 43% as MWCNT contents increases. These enhancements are primarily ascribed to the high aspect ratio, high modulus, strength and good dispersal of carbon nanotubes (CNT) in the hybrid nanocomposites.