Greater Tensile Strength Research Articles

Adapted the Mechanical Characteristics of Bio-Composite Sisal Fibres Material by Adding Aluminum Particles for Structure

The e-bike structure is increasingly developing, especially in terms of design, its strength is around 300 MPa in a maximum application of around 160 MPa, as is the case with the scooter bike structure. The strength of sisal, which is a composite reinforcing component, is made from natural fiber from pineapple leaves, which is then mixed with hemp fiber and carbon fiber. In mechanical structure materials, apart from the material being expected to have high yield strength, it is also expected to have good ductility. The reinforcement is then mixed with hard epoxy resin, soft epoxy, and 9 µm aluminum particles which are then stirred for 12 hours, until smooth and even. Mathematically, the improvement in this bio-composite is quite significant, obtained from the addition of carbon fiber. The ductility of the material is obtained from sisal, hemp and ductile epoxy mixed with hard epoxy resin. Because the quality of crop yields greatly influences the quality of the fiber, future agricultural processes need to be provided with counseling. The sisal fiber is a leftover product from community farming in the Subang area (Indonesia). Research using local materials is still able to obtain strength reaching ~480 MPa so it is still good. In this research, tensile tests were carried out 3 times so that it was found that the fiber taken from the rope had the greatest tensile strength, reaching around 480 MPa.

Improving mechanical properties and durability of polyether sealant in prefabricated buildings with titanium dioxide and graphene

The silane-modified polyether sealant is widely applied to fill the gaps between external walls in prefabricated buildings and to bear the deformation of joints. However, the weak tensile strength and poor ultraviolet and moisture resistance of sealant lead to severe degradation, posing threat to the building waterproofing and safety. To address the problems, titanium dioxide and graphene were adopted to improve the mechanical properties and durability of sealant. The tack-free time, tensile properties, ultraviolet resistance, and hydrophobic performance of pristine and modified sealant were investigated and the enhancement and erosive resistance mechanisms of modified sealant were revealed by microscale characterization. Results indicated that modified sealant with low content of titanium dioxide had greater tensile strength and ultraviolet resistance. The crystalline form of titanium dioxide and produced Si-O bond enhanced the ultraviolet resistance. Moreover, the 0.8% graphene-modified sealant possessed superior moisture resistance with 23% increased contact angle. Graphene increased the surface roughness and generated π-conjugated structure, improving sealant hydrophobicity. It is revealed that the enhanced properties were ascribed to the spatial structure of fillers and chemical bond energy. This work provides a novel sealant with high ultraviolet resistance and hydrophobicity, facilitating the development of durable and low-maintenance prefabricated buildings.

Experimental Study on the Impact of Using FRP Sheets on the Axial Compressive Performance of Short-Circular Composite Columns.

This paper conducts an experimental study on the axial compressive performance of FRP-steel-concrete composite columns. Nine short columns were produced and evaluated in the study, comprising of three concrete-filled steel tube reference columns and six FRP-steel-concrete composite columns, respectively denoted as "reference columns" and "composite columns". Two categories of failure modes, including shear failure and waist drum, were observed from the experiments. The failure mode may trend toward waist drum from shear failure as more FRP layers were used. The number of FRP layers had a direct effect on the level of compressive strength attained, with a greater number of layers resulting in a greater increase in compressive strength. Moreover, a greater tensile strength and higher elastic modulus of CFRP sheets are more effective at improving the compressive stiffness of the columns. Finally, a four-stage confinement mechanism for FRP-wrapped steel tube concrete composite columns is proposed and discussed, through which the damage mechanisms of the composite structures are more rationally characterized.

Recycling Waste Polypropylene to Produce New Composite Materials with Jute Reinforcements

Abstract Waste polypropylene (PP) polymer was collected, washed, dried and mechanically recycled into granules. Natural fibers are a sustainable and renewable resource, and in this work, Corchorus olitorius jute fiber was used as a reinforcing agent with waste PP. Jute fiber was collected from local market, cleaned, dried and cut into 1-2 mm in length for the production of waste PP-jute composites. The molecular structure of waste PP and virgin PP were characterized by the attenuated total reflection-fourier transform infrared (ATR-FTIR). The purpose of the current research was to examine the effectiveness of waste PP by comparing waste PP-jute composites and virgin PP-jute composites. The injection molding process was utilized to make jute fiber reinforced waste PP composites with various jute fiber loadings (5%, 10%, 15%, 20%, 25%, and 30% in weight).The same process was used to produce virgin PP composites reinforced with jute fiber. All composites undergo water absorption and tensile testing in order to assess the recycled PP. Injection molded virgin and waste PP's physico-mechanical, thermal, and tensile strengths are also examined. In comparison to waste PP, virgin PP has a 6% greater tensile strength and a 19% higher elongation at break. Results from waste PP-jute composites and virgin PP-jute composites did not significantly differ from one another. Products made from recycled PP can thus be both economically and environmentally viable.

Analisa Uji Tarik dan Uji Impak Pada Komposit Sekam Padi Perlakuan NaOH dan Pengisi Plastik Polypropylene (PP) dengan Matriks Resin BQTN-157

Analisa Uji Tarik dan Uji Impak Pada Komposit Sekam Padi Perlakuan NaOH dan Pengisi Plastik Polypropylene (PP) dengan Matriks Resin BQTN-157

Improvement Mechanical Properties of Epoxy Composite Reinforced with Sisal, Ramie and Carbon Fibers

In this paper, justification of mechanical characteristics is carried out to determine the ability of bio-composites to become structural composite bicycle frames capable of achieving strengths of more than 300 [MPa]. Sisal fiber is a natural fiber that is widely used as a composite fiber and is easy to cultivate. The fiber is believed to originate from Central and South America. Nearly 4.5 million tons of sisal fiber are produced annually worldwide, according to FAO. In building structural materials, in addition to structural strength, it is hoped that the material will also have good ductility. For this reason, the assembled bio-composite material consists of carbon fiber, ramie fiber, sisal fiber. The fiber is then mixed with hard epoxy resin, soft epoxy and aluminum particles 9 µm which are mixed until smooth and even. The significant increase in material strength is obtained from the strength of carbon fiber. Another thing is that the ductility of the material is obtained due to sisal and ramie which are bound by a mixture of epoxy resins. Because the quality of plant products is very dependent on the agricultural process, this study, the residual material was taken from the Subang (Indonesie) area and the ramie fiber was obtained from the Bandung market. Because agricultural cultivation in Indonesia still emphasizes the use of chemicals, basically this also has an impact on plant bio elements. However, research using local materials was still able to obtain strength reaching ~480 MPa, so it is still good. In this research, the tensile test was carried out 3 times so that it is known that the fiber taken from a rope has the greatest tensile strength which reaches around 480 MPa.

Effect of Chemical and Steam Explosion Pulping on the Physical and Mechanical Properties of Sugarcane Straw Pulp Trays.

Sugarcane straw fiber (SSF) samples were prepared by chemical pulping (CP) and steam explosion (STE). CP (5, 10, 15% NaOH + 0.2% w/w anthraquinone at 121 °C for 1 h) and STE pressure (1.77, 1.96, and 2.16 MPa at 220 °C for 4 min) SSF trays were molded with a hydraulic hot-press machine at 120 °C, 7 min, and 1.72 MPa. The yield (%) of SSF from STE (54-60% dry basis (db.)) was higher than CP (32-48% db.). STE trays had greater tensile strength than CP. However, STE's elongation and compression strength was lower than CP tray samples. The trays made from SSF using STE had less swelling in thickness, longer water wetting time, and a higher water contact angle than those made from CP. The micrographs displayed a smaller size of SSF obtained in STE than the CP. The appearance and area of peaks in ATR-FTIR spectra and XRD diffractograms, respectively, revealed that the STE trays had a larger residual lignin content from the lignin study and a lower crystallinity index than the CP trays. Moreover, the lightness values of the STE trays were lower than those of the CP trays due to lignin retention. The study results indicate that CP is the preferred method for producing SSF packaging material with high flexibility and fiber purity. However, when considering the specific SF of 4.28, the STE treatment showed superior physical and mechanical properties compared to CP. This suggests that STE could be an excellent alternative green pulping technique for producing durable biobased trays. Overall, the findings highlight the potential of STE as a viable option for obtaining trays with desirable characteristics, providing a sustainable and efficient approach to tray production.

Investigating the lap shear adhesion of coir and glass-fibre reinforced epoxy bonding to mild steel with varying volume fractions

Bonding synthetic fibres to metals to improve strength, durability, and corrosion resistance is a prevalent practise in the automotive, marine, and aerospace industries. Lap shear adhesion, a measurement of the bonding strength between composites and metallic substrates, is essential for structural integrity. The emergence of natural fibre composites as sustainable alternatives to synthetic composites makes it essential to investigate their lap shear behaviour and the effect of fibre volume fraction on composite properties. This research investigates the adhesion behaviour of coir and glass fibre epoxy composites to mild steel. Coir fibres, which are known for their resilience and tenacity, were treated with an alkaline solution to improve their adhesion to the resin. Samples of lap shear adhesion were prepared in accordance with ASTM specifications, and tests were conducted using a tensile machine. Increasing the volume fraction of coir or glass fibres decreased the bond strength, as demonstrated by the results. Due to the fibres’ greater tensile strength and rigidity, glass fibre composites exhibited superior strength. However, under tensile loading conditions, coir fibres exhibited superior adhesion to mild steel surfaces. SEM micrographs confirmed that coir composites exhibit shear failure while glass composites exhibit fibre pull-out behaviour. This study concludes by highlighting the engineering potential of coir fibres, considering their natural properties and cost-effectiveness. It is necessary to further optimise the fiber-matrix interface and comprehend the mechanical behaviour of coir composites in order to maximise their effectiveness. To assure the long-term durability of composite-metal joints, surface preparation, adhesive type, application procedure, and environmental conditions must also be considered. At a content percentage of 10%, glass fibres exhibited 100% higher shear strength compared to coir fibres in epoxy composites. Conversely, coir fibres at 10% content demonstrated approximately 75% greater shear strength than the values obtained with 40% glass fibres. The failure mechanisms observed are delamination or fibre fracture in the bonding area under tensile and shear loading. Increasing the fibre volume fraction reduces bond strength. Factors such as limited space for the matrix, tension concentrations, and the mechanical properties of the fibres contribute to weakened bonds. Glass fibres have better strength and rigidity than coir fibres, affecting load transfer and adhesion. Interfacial bonding is crucial, and maintaining it becomes more difficult with higher fibre volume fractions, resulting in weakened bonds.

EROSION-RESISTANT NANOCOATING DERIVED FROM POLYPROPYLENE AND BAMBOO-BASED BIO NANO CARBON (PP-BNC) TO ENHANCE ENERGY EFFICIENCY OF PETROLEUM PIPELINES

Oil and gas transportation efficiency is hindered by petroleum pipeline erosion where the pipelines are exposed to solid particles, viscous fluids, processing temperature and pressure, surrounding conditions and accompanied gasses. The current issue is to solve the erosion of petroleum pipelines problem by developing an erosion-resistant nanocoating. The development of erosion resistant nanocoating which is derived from polypropylene and bamboo-based bio nano carbon (PP-BNC) is the main focus of this research. PP-BNC nanocomposite were prepared by using thermal composition method to obtain the bamboo BNC or also known as carbon black, followed by coagulation method to obtain PP-BNC nanocomposites (10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt%) and lastly compression moulding method for the nanocomposite to become nanocoating thin film. During the thermal composition method, the grinded bamboo powder were combusted in tube furnace at 400°C, holding time for 30 minutes at 10°C/min rate in Nitrogen atmosphere. The solvents that were used are Toluene and Methanol during coagulation method. The structural, thermal and morphological properties of PP-BNC nanocomposites were characterised by Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Whereas the mechanical properties such as tensile and abrasion resistance along with its weight loss were evaluated by tensile and abrasion resistance tests. PP with 20 wt% BNC has the best results as the weight loss and wear index are the lowest which is 0.001 g and 0.033 mg/cycles respectively, great tensile strength with the value of 20.52 MPa and able to withstand high temperature up to 163°C where the highest temperature underwater is only up to 100°C.

Development of Films from Spent Coffee Grounds’ Polysaccharides Crosslinked with Calcium Ions and 1,4-Phenylenediboronic Acid: A Comparative Analysis of Film Properties and Biodegradability

Most polymeric materials are synthetic and derived from petroleum, hence they accumulate in landfills or the ocean, and recent studies have focused on alternatives to replace them with biodegradable materials from renewable sources. Biodegradable wastes from food and agroindustry, such as spent coffee grounds (SCGs), are annually discarded on a large scale and are rich in organic compounds, such as polysaccharides, that could be used as precursors to produce films. Around 6.5 million tons of SCGs are discarded every year, generating an environmental problem around the world. Therefore, it was the aim of this work to develop films from the SCGs polysaccharide fraction, which is comprised of cellulose, galactomannans and arabinogalactans. Two types of crosslinking were performed: the first forming coordination bonds of calcium ions with polysaccharides; and the second through covalent bonds with 1,4-phenylenediboronic acid (PDBA). The films with Ca2+ ions exhibited a greater barrier to water vapor with a reduction of 44% of water permeability vapor and 26% greater tensile strength than the control film (without crosslinkers). Films crosslinked with PDBA presented 55–81% higher moisture contents, 85–125% greater permeability to water vapor and 67–150% larger elongations at break than the films with Ca2+ ions. Film biodegradability was demonstrated to be affected by the crosslinking density, with the higher the crosslinking density, the longer the time for the film to fully biodegrade. The results are promising and suggest that future research should focus on enhancing the properties of these films to expand the range of possible applications.

Electrospun Poly(vinyl alcohol)-Based Conductive Semi-interpenetrating Polymer Network Fibrous Hydrogel: A Toolbox for Optimal Cross-Linking

Cross-linking of poly(vinyl alcohol) (PVA) creates a three-dimensional network by bonding adjacent polymer chains. The cross-linked structure, upon immersion in water, turns into a hydrogel, which exhibits unique absorption properties due to the presence of hydrophilic groups within the PVA polymer chains and, simultaneously, ceases to be soluble in water. The properties of PVA can be adjusted by chemical modification or blending with other substances, such as polymers, e.g., conductive poly[3-(potassium-5-butanoate)thiophene-2,5-diyl] (P3KBT). In this work, PVA-based conductive semi-interpenetrating polymer networks (semi-IPNs) are successfully fabricated. The systems are obtained as a result of electrospinning of PVA/P3KBT precursor solutions with different polymer concentrations and then cross-linking using “green”, environmentally safe methods. One approach consists of thermal treatment (H), while the second approach combines stabilization with ethanol and heating (E). The comprehensive characterization allows to evaluate the correlation between the cross-linking methods and properties of nanofibrous hydrogels. While both methods are successful, the cross-linking density is higher in the thermally cross-linked samples, resulting in lower conductivity and swelling ratio compared to the E-treated samples. Moreover, the H-cross-linked systems have better mechanical properties─lower stiffness and greater tensile strength. All the tested systems are biocompatible, and interestingly, due to the presence of P3KBT, they show photoresponsivity to solar radiation generated by the simulator. The results indicate that both methods of PVA cross-linking are highly effective and can be applied to a specific system depending on the target, e.g., biomedical or electronic applications.

Mechanical and thermal characteristics of steam‐exploded silane grafted Kigelia Pinnata fruit (KPF) fiber reinforced vinyl ester polymer composites

AbstractThe cellulose‐rich Kigelia pinnata aqueous fruit (KPF) fiber is a valuable natural biomass and has drawn attention as a renewable resource. Vinyl ester polymer matrix composites with better interfacial properties can have higher mechanical and energy dissipation properties. It can be obtained by the use of steam‐exploded silane‐grafted KP fibers with various fractions incorporated in the polymer matrix. KPF fiber grafting was maximized at 5% concentration after a steam explosion, removing hemicelluloses and lignin, thereby enriching a 23% crystallinity index (CI), leading to rich cellulose fiber. Steam explosion along with silane grafting increases the interfacial adhesion of the KPF fibers and the matrix through the interfacial bonding structure of Si–O–Si bonds, as confirmed by FTIR. A fiber with greater tensile strength was used to fabricate the vinyl ester composites. The highest tensile value of the steam‐exploded silane surface‐modified 30% KPF fiber‐reinforced composite was 125 MPa compared to the unmodified one due to increased stress distribution and restricted polymer chain movements. Compared to the untreated 30% KPF fruit fiber composite, steam‐exploded silane‐treated fiber showed a 12% higher impact energy due to faster load transfer, causing more impact energy absorption. A relatively higher interlaminar shear strength was shown for 30% treated KPF composites than for 30% untreated KPF composites. The steam‐exploded silane‐treated fiber (30%) composite shows the greatest thermal decomposition temperature of 399 °C because silane‐surface‐treated fibers contact the organo‐functional silane group in the polymer matrix. As a result, it obstructs polymer chain motions at higher temperatures, causing increased bonding strength.

PHYSICAL, MECHANICAL, AND MORPHOLOGICAL CHARCTERISTICS OF KAPOK (CEIBA PENTANDRA) TREE BARK AND EPOXY COMPOSITE WITH COATING (AESO) TREATMENT

Environmentally friendly composites continue to be developed from kapok tree fiber (Ceiba pentandra) with an epoxy matrix. This study aims to characterize the tensile behavior of single fiber and its composite, the pull-out properties of kapok tree fiber, and morphology of the fiber. Kapok tree fibers were varied in the NaOH solution and the AESO polymer. Single fiber tensile test and pull out refer to the ASTM D3379-75 and ASTM E399 standards, respectively. The composite manufacturing method used in this research was the infusion vacuum resin method with reference to the ASTM D638 standard. The results of the tensile test (composite) showed that the kapok bark fiber with the characteristics of NaOH + Coating had a greater tensile strength (197,88 Mpa), than that without treatment and NaOH treatment. Of all the characteristics of the kapok bark fiber, the highest value of the tensile strength was the fiber treated with NaOH + Coating (KNC). The results of fiber morphology showed proved that the NaOH treatment increased the surface hardness by eliminating the bonds of surface crystallinity, topography, water absorption, unit cell structure and fiber orientation. These results indicate that kapok tree fiber treated with 7% NaOH + coating with AESO polymer has high potential as a structural material to replace wood or textile materials.

Study on the tensile strength of plastic fiber reinforced M20 grade self-compacting bacterial concrete using a novel microbial technique Microbial induced calcite precipitation

Aim: The objective of this study is to quantify the influence of plastic fiber on the tensile strength of self-compacting concrete using a novel microbial technique Microbial induced calcite precipitation. Materials and Methods: There are 2 groups taken for the study and a total of 18 samples were prepared per group with Gpower (80%). Group-1 refers to the conventional self-healing concrete and group-2 refers to the plastic fiber reinforced self-compacting. concrete. The number of samples was calculated using clinical software by adopting the values from previously published research papers. The independent sample T-test has been carried out using SPSS software version 21 which shows a clear increment in the tensile strength of the fiber reinforced self-compacting concrete. Result: Tensile strength of plastic fiber reinforced self-compacting concrete increased by 3.73% when compared with the normal self-compacting concrete. The standard deviation of the tensile strength of plastic reinforced bacterial concrete was 0.28965. A significant difference between the two groups was observed with a p-value of 0.010 (p<0.05) Conclusion: From this experimental study it is concluded that the plastic fiber reinforced M20 grade self-healing concrete has greater tensile strength than the normal self-compacting concrete.

Molecular dynamics simulations of copolymer compatibilizers for polylactide/poly(butylene succinate) blends.

The effects of the molecular architecture of polylactide (PLA)-poly(butylene succinate) (PBS) copolymers on their compatibilization efficiency in immiscible PLA/PBS blends were studied using atomistic molecular-dynamics simulations. The results showed that the diblock copolymer is the most efficient at mixing with PLA and PBS homopolymers and reducing the interfacial tension of the blend. Tensile properties of the compatibilized blends were examined using uniaxial deformation simulations. Deformation behaviours of the blends at the molecular level were revealed. Both the structure (i.e. linear and branch) and the monomer sequence of the copolymers were found to affect the tensile performance. The system with a diblock copolymer showed a much greater tensile strength and elastic modulus than the other compatibilized blends. Comparing between triblock and graft copolymers, the former yielded the blends with better tensile performance than the latter. Our results suggest that copolymers with a linear structure, especially the diblock one, could be good candidates for the compatibilizer of PLA/PBS blends.

Fabrication, Mechanical Characterization, and Ranking of Shell Ash Reinforced Al-7075-Based Hybrid Composites

In the research article, the fabrication of Al-7075-based hybrid composites was done by stir casting technique with the addition of a mixture of crab shell ash (CSA), oyster shell ash (OSA), and snail shell ash (SSA). The mixtures of CSA, OSA, and SSA (MCOSA), CSA and OSA (MCOA), CSA and SSA (MCSA), as well as OSA and SSA (MOSA) with weight percentages in a range of 1–3% were added to the base material. The specimens were prepared according to the ASTM standards and tested for mechanical properties. The hardness, as well as impact, flexural, and tensile strengths of the composites, were increased as the amount of reinforcement to the base metal was increased, and compressive strength was decreased. The greatest tensile strength, tensile modulus, and compressive strength values were observed for the composite designated with AlOSA3. The maximum flexural strength and hardness values were observed for the compositions AlOS21 and AlCO12, respectively. Two techniques (TOPSIS and VIKOR) were successfully applied to the mechanical attributes of composites. The ranking results of both methods were compared. The ranking results for TOPSIS and VIKOR were the same for the index value 0.25. The composites filled with aquatic waste fillers can be used for automotive applications concerning their enhanced mechanical properties compared to the Al-7075 metal alloy properties.

Wire arc metal additive manufacturing using pulsed arc plasma (PAP-WAAM) for effective heat management

To address the materials processing challenges resulting from high levels of heat input in wire arc additive manufacturing (WAAM), a novel wire arc metal additive manufacturing method using pulsed arc plasma (PAP-WAAM) was developed in this study. In this method, the pulsed arc plasma generated by the pulsed voltage was used as the heat source. Owing to the applied pulsed voltage, the arc plasma was alternately ignited and extinguished during additive manufacturing. By adjusting the relative positions of the tungsten electrode, filler wire, and substrate, the arc plasma was ignited between the tungsten electrode and the filler wire. This increased the proportion of discharge energy allocated to the filler wire, thus reducing the overall heat input required for material deposition. Furthermore, no heat was transferred to the deposited material because the arc plasma was extinguished during the discharge interval. Consequently, the previously deposited material was rapidly cooled. Preliminary experimental results showed that the newly developed PAP-WAAM process used 37 % less heat input than the conventional gas tungsten arc welding-based WAAM (GT-WAAM) process at the same wire feed speed of 350 mm/min. The PAP-WAAM process yielded smaller melt pools, higher cooling rates, and less heat accumulation than the GT-WAAM process, which was mainly attributed to the combined effects of low heat input and efficient heat dissipation by the pulsed discharge during PAP-WAAM. As a result, PAP-WAAM produced finer geometric features and microstructures as well as greater tensile strength than GT-WAAM.

Tensile strength of various bamboo species tested with different shape of test specimens

Bamboo has a different tensile strength at the bottom, middle and top, both at the node and internode part of the bamboo. Tensile strength obtained by tension test with several standard testing methods that use different specimen shapes in the testing process. This study compared standard test methods that use dog bone-shaped specimens and strip-shaped specimens to see the correction of the tensile strength of bamboo from the same culm but tested differently. The test specimens are carried out from the area of Asahan Regency (including Tanjung Balai City), Batubara Regency, and Simalungun Regency, which are located in the eastern region of Sumatera Utara. The tension tests are carried out from the bottom, middle, and top section of the bamboo culm, and tested using a Universal Testing Machine. The average water content from bamboo species tested in this study is 14%. The strength ratio of the bottom, middle, and top section (B:M:T ratio) of dog bone-shaped specimens is 1.57: 1.24: 1, while B:M:T ratio of the strip-shaped specimen is 1.15: 1.05: 1. The tensile strength difference of dog bone-specimens from node and internode section is 31.89%, while the difference from the strip-shaped specimen is 13.81%. These results indicate that the bottom part of the bamboo culm has greater tensile strength, regardless of the shape of the specimens, followed by the middle part, and the top part respectively.

Enhanced dielectric constant and mechanical investigation of epoxidized natural rubber with TM-doped CeO2 nanocomposites

The dielectric constant and mechanical properties of epoxidized natural rubber (ENR) were improved by forming composites with CeO2 and various types of transition metal (TM) doped CeO2 nanoparticles (TM-doped CeO2 such as Fe-CeO2, Co-CeO2, Ni-CeO2, Cu-CeO2, Mn-CeO2 and Zn-CeO2). The CeO2 samples and TM-doped CeO2 nanoparticles were prepared using a co-precipitation method at room temperature and were calcined at 600 °C. The composites were prepared with 2 phr of CeO2 and TM-doped CeO2 nanoparticles referred to as CeO2 @ENR, Fe-CeO2 @ENR, Co-CeO2 @ENR, Ni-CeO2 @ENR, Cu-CeO2 @ENR, Mn-CeO2 @ENR and Zn-CeO2 @ENR. A carbon black (CB) and ENR composite was also prepared for comparison and referred to as CB@ENR. The morphology, phase and valence states of prepared samples were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), field emission scanning electron microscopy, X-ray photoelectron spectroscopy. The samples exhibited XRD peaks and TEM-selected area electron diffraction corresponding to a face centered cubic CeO2 structure, confirming a single phase. They showed average crystallite sizes in the range of 10.5 ± 0.3–15.0 ± 1.4 nm. All TM-doped CeO2 @ENR composites exhibited higher dielectric constants and lower dielectric losses at room temperature as a function of frequency than that of CB@ENR composites. A maximum value of ∼392.6 at 102 Hz for the Cu-CeO2 @ENR composite was shown. Additionally, this dielectric constant was about 3 and 4.7 times higher than those of CeO2 @ENR and CB@ENR, respectively. Also, the breakdown strength of the Cu-CeO2 @ENR nanocomposite was increased compared to CB@ENR. Furthermore, TM-doped CeO2 nanocomposites display increased torque, higher 100% & 300% moduli and greater tensile strength caused by nano-filler affects. As a result, this research may open up new avenues for the development of insulating elastomers.

Tensile Strength and Microstructure of Rotary Friction-Welded Carbon Steel and Stainless Steel Joints

Due to the different properties of the materials, the fusion welding of dissimilar metals may be difficult. Structural irregularities may form as a result of various phase transformations during welding. Solid-state welding, as opposed to fusion welding, occurs below the melting temperature. As a result of the melting and solidification phenomena that happen in fusion welding, solid-state welding is expected to reduce the potential for phase transformation. This paper describes the use of a rotary friction welding technique to join carbon steel and 304 stainless steel. The purpose of this work is to investigate the characteristics of rotary friction welding (RFW) when joining 304 stainless steel to carbon steels with different carbon contents. Experiments were carried out on the RFW of low- and medium-carbon steels with 304 stainless steel. The investigation was carried out using the Taguchi method of experimental design. The joints’ tensile strengths and microstructures were evaluated. The parameters that had the greatest influence on the tensile strengths of the welding results were identified. The combination of parameters resulting in the greatest tensile strength is also suggested. A microstructural examination of the weldment revealed mechanical mixing and interlocking.