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Magnesium (Mg) & its alloys are favourable for orthopaedic & cardiovascular medical device fabrication applications, but holds a natural ability to degrade biologically when put with aqueous solution of the substances and/or water-saturated tissue in the context of a living organism. Mg alloys nature to corrode inside the living organism body is mainly attributed to the excessive rates of corrosion of Mg. Poor corrosion resistance possessed by Mg decreases the mechanical properties of the implants, and adds toxic effects on the bone metabolism. A potential method for increasing Mg alloy resistance to corrosion without changing its properties is by the protective polymeric deposit coatings. Moreover, to impart better mechanical and biocompatible aspects to Mg based materials biopolymers have been used as a composite constituent. This review is based on such composite materials constituting Mg and biopolymers. Their resulting favourable mechanical and osteopromotive properties in conjunction with biocompatibility may help the clinicians to fix the existing orthopaedic related issues.

Conducting polymer nanocomposites (CPNC's) are promising materials for sensor devices possessing design pliability, good sensitivity, and low temperature operation. For producing conducting polymer nanocomposites with tunable morphology, the soft template procedure is one of the advantageous aspects as reported from in-depth literature. Since the diameter and aspect ratio of conducting-polymer nanomaterials have affected the charge-transport properties, hence, the fine tuning of their structures is important to enhance sensitivity. This review has focused on the CPNC's membranes, insulative-polymers with conductive-fillers based CPNC's (IPCFCPNC's) and conductive-fillers based polymer nanocomposites (CFPNC's) which have been incorporated in many prior literary sources including the usage of strain sensors in some sensing applications for detection pressure, gas humidity, etc. As the review sheds light on incorporating specific types of nanofillers, such as graphene or carbon nanotubes or conducting filling-agents, into the CPNC's membrane matrix and insulative-polymeric-matrices, it will be possible to improve their mechanical stability, enabling them to be used for high-performance sensing applications. In addition, the review has evident that by using advanced fabrication techniques, such as electrospinning, it is possible to create thin, flexible CPNC's membranes that exhibit high sensitivity and stability towards target analytes. Therefore, the feasibility of CPNC's, IPCFCPNC's, and CFPNC's in sensor applications has thoroughly been reviewed for the purpose to realize the novel flexible CPNC structures and their other aspects of applications that may cater to new horizons in high-end smart flexible sensing applications. Additionally, the advanced discovery is to combine conductivity measurement and rheology analysis using a new emerging class of CPNC's, IPCFCPNC's, and CFPNC's for remarkable electrical properties. It is highly appealing to find out more about novel CPNC's, IPCFCPNC's, and CFPNC's, and their role in sensor matrices, considering their unique properties. Based on conducting polymers (CPs), and insulative-polymers with conductive filling-agents that have been reported during the past forty years, the properties and performance of sensing matrices have been investigated by incorporating the diverse carbon-based nano-additives and other nano filling-agents. Furthermore, another area of interest is the use of CPCs, and insulative-polymers with conductive filling-agents for the development of bio-sensors. CPCs, and insulative-polymers with conductive filling-agents can be functionalized with biological molecules such as enzymes, antibodies, and nucleic acids, to create highly sensitive sensors for the detection of various biological markers, including glucose, lactate, and pH. Along with myriads of illustrations in accordance with the CPs and their composites with nanoparticles, carbon materials, or conductive filling-agents with insulative-polymeric-matrices etc., their salient characteristics have been enumerated in this comprehensive review. Additionally, CPNC's, IPCFCPNC's, and CFPNC's-sensing devices will have to improve their analytical performance for a widespread spectrum of multifaceted sensing applications in future research trends.

The aim of this research work is to investigate the effect of strain rates and temperatures on the mechanical properties of an equiatomic copper-nickel (Cu–Ni) alloy with a pre-existing faceted Σ3 [111] 60° {11 8 5} grain boundary. Molecular dynamics simulations conducted in this scrutiny focuses on understanding the tensile behaviour of bicrystalline equiatomic Cu–Ni alloys (denoted by Cu50Ni50) under various thermodynamic conditions. The uniaxial tensile deformation simulation was carried out at various strain rates (108, 109 and 1010 1/s) in conjunction with different conditions of cryogenic temperature (100 K), room temperature (300 K) and high temperature (500 K). The authors found that the yield stress and Young's modulus of the bicrystalline Cu50Ni50 alloy were highest at the cryogenic temperature, and decreased as the temperature increased. To add on, the yield stress of the bicrystalline Cu50Ni50 alloy increased with an increase in the strain rate value. From the microstructural and dislocation analysis point of view, it was observed that the formation of dislocations was lowest at the cryogenic temperature. Interestingly, at the yield point, the coherent twin boundary tip act as the nucleation site for the dislocations for cryogenic temperature condition. These findings shed light on the relationship between the temperatures, strain rates, and the mechanical properties of Cu–Ni alloys, which will aid in reporting the optimized conditions for their desired engineering applications. It is also proposed that tailoring of the tensile properties is achievable by exposing Cu–Ni alloys to various environmental conditions (cryogenic, ambient, and elevated temperatures with different applied strain rates).

The objective of this review article is to report the tribological characteristics of hybrid composites comprising ceramics and aluminium, particularly in the elevated temperature conditions, and to explore their potential utility in the field of engineering. The authors have also comprehensively reviewed the impact of ceramic reinforcements on the tribological properties, including friction, wear, and solid lubricant behaviour, of composites when subjected to high temperature conditions. The tribological performance of the hybrid composites was assessed through the utilisation of experimental methodologies such as wear testing, friction analysis, and surface characterization techniques. The outcomes of this review report will enhance the comprehension of the potential of these composites for high temperature engineering applications, including but not limited to the automotive, aerospace, and manufacturing sectors.

The present study focuses on the fabrication and characterization of an innovative epoxy-based hybrid composite, designed to enhance its mechanical properties by incorporating three distinct reinforcing agents that are Millettia pinnata leaf powder, alumina/boron nitride particles, and glass sheets. This hybrid composite aims to combine the individual strengths of alumina/boron nitride particles reinforcements, ultimately achieving a superior material with enhanced mechanical strength. The selection of these reinforcements was based on their unique properties, such as biodegradability and eco-friendliness of Millettia pinnata leaf powder, high strength-to-weight ratio of alumina/boron nitride, and excellent mechanical properties of glass sheets. The optimized weight fraction of each reinforcement was determined through a series of experimental trials to maximize the composite's performance. The characterized thermo-mechanical properties included tensile strength, flexural strength, impact strength, and hardness. Additionally, microstructural analysis was performed using the scanning electron microscopy to examine the interfacial bonding between the matrix and reinforcements, offering insights into the composite's overall integrity. The findings revealed that the incorporation of Millettia pinnata leaf powder, alumina/boron nitride, and glass sheets led to significant improvements in the mechanical properties of this hybrid composite. The composite exhibited enhanced tensile and flexural strength, resulting from the reinforcing effects of alumina and glass sheets. Comparatively, the mechanical properties of boron nitride composites tend to be higher than that of the alumina composites. Maximum tensile strength, flexural strength, impact strength and hardness for the boron nitride composites are 312.21 MPa, 19.53 MPa, 53.68 kJ/m2 and 103.25 HRL, respectively at composition of 6 grams of boron nitride and 6 grams of Millettia pinnata leaf powder; whereas, for the alumina composites these values are 211.84 MPa, 15.46 MPa, 44.12 kJ/m2 and 101.23 HRL at composition of 6 grams of alumina and 6 grams of Millettia pinnata leaf powder. The results reported in this study will be helpful in accelerating the industrial applications of epoxy-based hybrid composites.

Bio-composites have lately established wide applicability in various industrial sectors such as automobile, construction, packaging, and coatings. Due to their global abundance, natural fibers and starch have been one of the most tested raw materials to be utilized as bio-composite reinforcements. This investigation aims to fabricate corn starch (CS) reinforced vetiver cellulose fibers (VCF) composites using the solution casting method. For the VCF reinforcement, alpha (α)-cellulose was synthesized from the vetiver roots and post-converted into nano-cellulose using the ball milling technique. Various compositions comprising 0, 5, 10, 15, and 20% (by weight) of this α-cellulose were inserted as reinforcement to commercially available CS matrix. The fabricated composite specimens were put to tensile, water absorption capacity, Fourier-transform infrared spectroscopy, and contact angle determination tests to evaluate the film properties. Crystallinity and failure morphology analysis of the composites was captured using the X-Ray Diffraction and scanning electron microscopy techniques, respectively. Results reveal that the incorporation of VCF in the CS matrix domain enhances the mechanical properties of bio-composites. Furthermore, the water absorption capacity decreased, and the contact angle increased; thereby predicting the composite’s potential application as a lightweight food packaging material.

Hydrophobic coatings basically decrease the wettability of surface due to the presence of nanostructures on it. In this research work, nanozirconia sol was prepared by the sol-gel method and further hydrophobically modified using the hexamethyldisilazane (HMDS). Prepared sol was coated on the glass substrate and then analysed for its wetting behaviour. Three samples with different HMDS ratios mixed to Zirconia sol were coated, and analysed for surface morphological parameters through the atomic force microscopy and field emission scanning electron microscopy techniques. The wetting behaviour was analysed by studying the water contact angle and surface free energy of the samples. Here the transmittance was measured by transmittance metre at regular intervals for 30 days. Functional group determination was done by Fourier transform infrared spectrometer that confirmed the formation of Zirconium nanoparticles. Maximum contact angle of 101.2° was observed that showcased the hydrophobic properties. Hydrophobic coating was then successfully prepared, and sample with 2:1 ratio of Zirconium nanoparticles and HMDS showed the best hydrophobic nature amongst all the coatings prepared in this investigation.

In this research work, polyvinyl alcohol (PVA)-graphene (Gr) nano composite films were fabricated by incorporating the functionalized graphene (f-Gr) for different periods of refluxing and vacuum oven time. The graphene particles were functionalized through nitric acid (HNO3). Various tests were conducted to estimate the properties and characteristics of this composite. Fourier transform infrared spectroscopy (FTIR) results confirm the bonds of carboxyl, hydroxyl and carbonyl groups, manifested of functionalization of graphene. Scanning electron microscopy was performed to investigate morphology and transparency of f-Gr nano-particles in nano-composite films. Water absorption test was carried out to evaluate water absorption (%) in the PVA based composite films. The result revealed that water absorption rate of the composite decreased with increasing refluxing time at constant vacuum oven time of f-Gr reinforced composite. Dynamic mechanical analysis (DMA) showed that the value of storage modulus was higher for PVA-f-Gr nano-composite films compared to neat PVA and PVA-Gr composite over the entire range of temperature, which lead to explore this composite material for the vibration isolation applications. Glass transition state (Tg), loss modulus and the damping factor (tan δ) of the PVA-f-Gr nano composites films were highly affected by the addition f-Gr nano crystals in the PVA matrix. The value of tan δ for f-Gr nano composite is obtained both higher as well as lower compared to PVA-Gr film for the varying vacuum oven time and refluxing time. Electrical analysis indicates an enhancement in conductivity of PVA with introduction of f-Gr nano particles. After evaluating the high damping characteristics of this composite, the authors perceive that it may be utilized to reduce noise transmission and as a shock absorber vibration isolator.

This review article addresses the potential for biopolymer-based composites made from agricultural waste biomass to replace conventional materials in a sustainable and responsible manner. The composition and manufacturing method of biopolymer-based composites are described in the article, along with some of their distinctive qualities and benefits, such as their low cost, renewable nature, and biodegradability. The article also shows a number of real-world uses for these composites, including packaging, construction, vehicle parts, biofuels, soil amendments, and medical uses. Overall, the article highlights the potential of biopolymer-based composites made from agricultural waste biomass for lowering waste generation, decreasing dependency on non-renewable resources, and boosting sustainability in a variety of industries.