Aluminum alloys have become an essential material in many modern applications, such as automobiles, marines and aviation industries. It is expected that more applications will heavily depend on aluminum alloys to reduce the weight and maintain safety standards, many previous studies have done in this regard. Numerous of these applications’ parts could be subjected to different loading and environmental conditions. This includes wearing stress and loss of the surface properties. To address these issues, intensive researches have been conducted aiming to improve aluminum wear resistance. However, there is an increasing demand to provide a comprehensive understanding of the mechanisms of enhancing wear resistance. Preparation of nano-materials combined with aluminum alloy can be made in several known metallurgical methods. One of the most important difficulties and challenges faced in the manufacture of these nano-materials is to obtain a homogeneous mixture that does not have manufacturing defects. The present work aims to process and evaluate the Nano-hybrid composites of with different ratios of (Cu+Ti) mixed with AA7075 by using the liquid stir casting method by using (pin-on-disc) wear testing apparatus. The results showed when using multiple speeds and different loads in practical experiments, that the volumetric wear loss increase from 2.8 mm3 to 29.89 mm3 for zero–Nano and from 0.889 mm3 to 3.09 mm3 for 0.8 %+0.3 % (Cu+Ti) composite at speed 100 to 300 respectively. And from 12.81 mm3 to 0.889 mm3 at 25N. The coefficient of friction is reduced with the addition of reinforced material at 0.8 %+0.3 % (Cu+Ti) composite from 0.172 to 0.05. The hardness (BH) of the prepared composites increases with increasing the amount of hybrid Nano–reinforced materials. The enhancement percentage of 25.4 % is attained compared to the matrix material. These additions, which were in certain proportions, improved the mechanical properties
With the development of techniques for the use of gears and their many shapes and types, the mechanical need for them has become great, especially in the use of them in the field of cars, and the most important of these types are bevel gears, as these gears are considered essential in differential gears. The use of differential gears in mechanics in general helps to reduce noise in the movement, but there must be vibration resulting from this movement, and accordingly, bevel gears and the effect of rotating gears on free vibration have been studied. Variable gears were used according to a simulation program and the study of the free vibrations that occur to them. The effect of rotational speed on the natural vibration greatly affects the transmission of movement in the car and increases the fault distortions that occur in the differential gearbox. The result shows the natural vibration reached at the speed of 5000 rpm, and the value of the vibration reached 3564.5 Hz, which is the highest value compared to the remaining speed. The distortion at a speed of 1,000 rpm. The process of rotation and natural vibration affects the deformations and stresses that get on the gears themselves. The natural vibration is greatly reduced when the number of clamping places for the differential gear is increased. Compared to the presence of two spinning tires, the vibration value reduced. At a rotating speed of 5000 rpm, it is known that increasing the rotational speed raises the value 3015.9 Hz with one tire revolution with one tire rotation, the huge strains influence the little gears in the differential gearbox. The greatest value of distortion is 0.00067 m at 5000 rpm, which is the largest value of deformation compared to the rest of the employed rotational rates with one tire revolution.
This paper presents the dynamic response related to varying in indispensable parameters of pulley-belt system, a manufactured pulley-belt system has been built and experimental results have been obtained and analyzed accurately which reveal the effects of these parameters on indicated system. Manufactured system assembled from heavy steel structure, variable speed DC motor, speed measurement tool (tachometer), two shafts of 25 mm diameter, four pillow block ball bearings, V-belts and pulleys with different diameters (10, 15, 20, 25) cm. The fabricated system presents mechanical characteristics likes serial changing in rotational speed (500 to 2000) rpm, diameters ratios (1 to 2.5) and center distance (27 to 120) cm. accelerometer ADXL335 (3-axis) mounted on bearing brackets of drive and driven shafts and connected to Arduino type mega 2560 (microcontroller) which sending the data of vibration to the laptop in order to display it in Sigview software as a time and frequency domain band by FFT (fast fourier transform). Results showed the effects of change the values of rotational speed, center distance, and diameters ratios on vibration response of pulley-belt system.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.