Effects of Heat Treatment Techniques on the Fatigue Behaviour of Steel Gears: A Review

Heat treatment of gears are fundamental to efficient and reliable gear production because of its contribution to the overall cost of manufacturing. Different heat treatment techniques are targeted to improving hardness, ductility and strength to minimize material degradation or wear. However, several heat treatment methods had led to gear tooth distortion such as shrinkage of tooth thickness which eventually affects the contact angle. The study therefore focused on some selected heat treatment on gears and their effects on gear applications. from the reviewed heat treatment techniques, distortion is a common occurrence that result to gear fatigue. Also, it was noted that most times, the medium for quenching and most importantly, variation in the concentration affects the gear accuracy. Thus, local fracture and material loss ensue. Nevertheless, the study further suggested the use of empirical model and simulation approach for stress prediction

Electron Tunneling, Performance Analysis and Prospect of Micro-energy Generation in Ringwood (Syzygium Anisatum) Dye-sensitized Solar Cell

Energy continues to be the currency that drives all technology. Thus, the quest for energy remains vital to energy sustainability. In the wake of several adverse consequences of indiscriminate combustion of fossil fuel, there is an urgency to exploit our natural environment for ecologically benign alternatives. Ringwood also known as S. anisatum or Aniseed is a common sight in many ornamental gardens. It provides the customary thick layer of plush greenery typical of such settings. In addition, its characteristic aromatic leaves are capable of attaining a height of 45 metres. These attributes consolidated in the choice of Ringwood as a suitable candidate with a rich and viable store of solar energy. This gave the impetus to convert this S.anisatum store of photons of sunlight to electricity. Preliminary phytochemical screening results revealed the presence of phenols, flavonoids, tannins, glycosides, terpenoids and protein, a wide chromophore selection for charge transport. The study of S.anisatum absorbance-wavelength properties with UV/VIS spectroscopy shows S.anisatum dye extract having multiple peak absorbances with its optimum in the near ultraviolet region although, it absorbs optimally in the visible region of the electromagnetic spectrum. This is a Porphyrin dye characteristic, a desirable attribute that facilitates wider spectrum of solar energy absorption. The outpu

Corrosion Behavior of Mild Steel in Different Concentrations of Ethanol Beverages

Corrosion behavior of mild steel was investigated in different blends of ethanol solution. Potentiodynamic polarization tests and weight loss analysis were carried out to study the corrosion polarization tendency of the various blends of the solution on mild steel using water as a control medium. Scanning electron microscope with energy-dispersive spectroscopy was employed to characterize the surface morphologies as well as the elemental composition of each material subjected to corrosion tests. The result of the potentiodynamic polarization curves showed that water contributed to the corrosion rate of the material. Further to this, ethanol samples behaved passive against corrosion degradation. The result of the weight loss indicated that corrosion of the mild steel actually took place. More so, the SEM/EDS revealed the microstructural behavior of the surface oxides, spots, cracks and corrosive pits at the interface with the ethanol environment. This study will help in improving the mechanical properties of mild steel material employed to produce spur gear that will reliably function in an ethanol environment

Effect of Bandgap Vs Electron Tunneling on Photovoltaic Performance of Ringwood (Syzgium Anisatum) Dyesensitized Solar Cell

The quest for more energy remains vital to energy sustainability. In the wake of several adverse consequences of indiscriminate combustion of fossil fuel, there is an urgency to exploit our natural environment for ecologically benign alternatives. This search led to S. anisatum dye being investigated for its prospective application in dye-sensitized solar cells. Phytochemical screening revealed the presence of phenols, flavonoids, tannins, glycosides, terpenoids and protein, presenting a wide repertoire of chromophore selection for charge transport. UV/VIS spectroscopy showed that S.anisatum dye exhibits multiple peak absorbances of radiation within the near ultraviolet and the visible region of the electromagnetic spectrum of light. The consequent adsorption of its chromophores into titanium structure, amplitude of interatomic vibrations of the novel structures formed in S. anisatum dye were subject of our investigation. The outcome shows TiO2/S.anisatum dye interface reveals the impact of orientation on output photovoltaic performance of S.anisatum dye-sensitized solar cells with a short circuit current of 0.07 mA, open circuit voltage of 68.8 mV, fill factor value of 0.84 and the output efficiency was 0.027 % using KBr electrolyte. This is a comparatively good result considering previous records of dye-sensitized solar cell photovoltaic performance. The significance of these results was re-analyzed from molecular perspective with the aid of scanning electron microscopy (SEM). A need to boost the efficiency necessitated the interpretation of SEM micrographs using Gwwydion software program. These presented possible areas for charge transport within the electron shells of S.anisatum dye nanocomposite, and regions where tunneling occurred providing a much needed insight for future studies. Consequently, this study was expanded to accommodate the influence of bandgap on electron occupancy in S.anisatum shells. This elucidation captures the molecular dynamics of charge transport versus tunneling, consequent upon output performance of dyesensitized solar cell technology explained with quantum principles. The application of this work is particularly relevant in modelling, photovoltaic simulations and building energy efficient models

Electrochemical study and gravimetric behaviour of gray cast iron in varying concentrations of blends as alternative material for gears in ethanol environment

The phenomenon of chemical degradation of mild steel materials under ethanol environment is becoming alarming. In order to study the electrochemical, thermal and mechanical behaviour of gray cast iron in this environment, this paper deals with the investigation of gray cast iron sample in varying concentrations of different ethanol blend solution. The electrochemical behaviour of gray cast iron sample was studied in ethanol concentrations of A – 42%, B – 40%, C – 28%, D – 43% and E – 45% using distilled water as control medium. Observations of the microstructures after the test showed that mainly oxides and corrosion products dominate the surfaces. However, some areas showed some cracks which are less severe. Also, the thermal gravimetric analyses of samples after the electrochemical test showed that, there was reduced thermal decomposition which suggests its good performance for gear application. Further to this, the micro-hardness results showed that the material maintained its mechanical properties despite the interactions with the solvents