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The investigation on the effect of sintering temperature and time intervals on workability behaviour of Al-SiC powder metallurgy composites during cold upsetting was attempted in the present work. Three levels of sintering temperature and time have been considered to evaluate their effect on workability behaviour. The amount of SiC reinforcement content has been varied as 0%, 10% and 20%. The experimental results were analyzed for workability under triaxial stress state condition as a function of the relative density. The Formability Stress Index (β σ ), the Formability Strain Index (β ε ), stress ratio parameters namely σ θ /σ eff and σ z /σ m were obtained for all the cases. As a result, the exhibited tremendous variations in the various parameters for different sintering temperatures and time intervals were studied and reported.

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In practice, lubricants are used to minimize the friction and wear of frictional surfaces. The disposal of mineral-based lubricating oil possesses environmental issues and forced the development of bio-degradable lubricating agents. The simultaneous mono-dispersion of metallic and metal oxides nanomaterials into lubricating agents may concurrently reveal superior thermo-physical and rheological characteristics. This paper proposes an experimental and theoretical investigation on the dynamic viscosity enhancement of flat platelets textured Graphene/NiO-coconut oil hybrid nanofluids. The results reveal that the dynamic viscosity enhancement of hybrid nanofluids increases with nanomaterial concentration and decreases with temperature. The squat hybrid nanomaterial concentration has less collusion probability and dynamic contact between the mono-dispersed hybrid nanomaterials as it has enough interfacing gaps to conquer superficial surface energy. The high nanomaterial concentration revamps the formation of lamellar-composite agglomerated particles and enhances the dynamic viscosity of base fluid. Further, a theoretical correlation is recommended to estimate the dynamic viscosity of hybrid nanofluid with minimum margin of deviation using artificial neural network (ANN).

Pyrolysis has recently emerged as a viable and sustainable approach for assessing the bioenergy potential of agricultural waste. Indian almond fruit (IAF) has the potential for bioenergy recovery for heat and electricity generation, whereas, the characterization and the kinetics data of IAF have never been explored. In this research, the IAF biomass was involved in proximate, ultimate and chemical analysis for the complete characterization of biomass. Further, the pyrolysis behaviour and kinetic analysis of IAF were investigated by thermogravimetric analysis (TGA) technique using five heating rates such as 5°C/min, 10°C/min, 15°C/min, 20°C/min and 25°C/min, respectively. Kinetic analysis was performed on the IAF biomass using different kinetic models such as Kissinger, Friedman, Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO). Furthermore, thermodynamic parameters were determined using the decomposition data obtained from the TGA curve. A characterization study revealed that the IAF biomass displayed a heating value of 18.31 MJ/kg. The carbon and hydrogen contents were noted as 50.72% and 4.98%, respectively, and no traces of sulphur were observed. The IAF biomass exhibited the maximum lignin content of 21.14%. TGA results revealed that the IAF biomass decomposed in three stages, stage 1: 35°C to 110°C, stage 2: 110 °C to 240°C and stage 3: 240°C to 400°C. Higher mass loss was seen in stage 3 due to the simultaneous degradation of cellulose, hemicelluloses and lignin. Activation energy calculated by Kissinger, Friedman, KAS and FWO exhibited as 12.23 and 9.15 kJ/mol – 19.09 and 26.10 kJ/mol – 132.57 and 32.60 kJ/mol – 142.33 kJ/mol, respectively. Furthermore, thermodynamic analysis of IAF biomass displayed that the pyrolysis process was a spontaneous and endothermic process. In addition, the pyrolysis characterization of various biomass investigated by the previous researchers has been compared with the present results.

In the past decades, considerable efforts have been made for the development of energy-efficient and eco-friendly convective heat transfer and lubricating agents because of growing energy demands, precision manufacturing, miniaturization and sustainability issues. In this study, different concentrations of graphene–sunflower oil nanofluid were prepared and their thermal conductivity was experimentally investigated and compared with the correlations of similar researches found in the literature. The morphology of graphene nanoplatelets was appraised by X-ray diffractometer (XRD) and scanning electron microscope (SEM). The results show that the thermal conductivity of nanofluid was enhanced with temperature and nanoparticles weight fraction. The nanoconvection at high temperatures, less meandering mobility of graphene nanoplatelets and high kinematic viscosity of graphene nanofluids at low temperatures were identified as the key factors for the thermal conductivity enhancement. Further, the concentration and temperature-dependent theoretical correlation were proposed for estimating the thermal conductivity of graphene nanofluids using backpropagation algorithm of artificial neural network (ANN) with the minimum margin of deviation.

Natural fibers are good substitute for polymer fibers due to its better characteristics like biodegradable, low cost and no harmful release. The purpose of this research is to identify a natural fiber with low cost and good characteristics. Hence, in this research, an attempt has been made to analyze the physical, chemical and thermal properties of banana flower pistil fiber (BPF). The fibers were involved into chemical treatment such as alkali (5%, 7.5% and 10%). The effect of chemical treatment on the properties of fiber was analyzed. Structural properties were analyzed by X- Ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The thermal properties were tested by Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). Further, the water absorption ability of the treated and untreated fiber was investigated. Results showed that the chemically treated fiber (5% alkali) displayed good physical, chemical and thermal properties compared to untreated fiber. Hence, the chemically treated BPF could be useful in the fabrication of bio-composites for industrial applications.