Articles
Publication Date: 2026
International Journal of Engineering, Transactions B: Applications (1728144X)39(1)pp. 44-58
Bevel gears are a kind of gears that transmit power between two intersecting shafts. Bevel gears with Octidal and spherical involute profiles are the most common types of bevel gears. The profile of spherical involute teeth is a three-dimensional complex surface, requiring an accurate geometric definition calculation. Due to this complex geometry, modeling, stress-strain analysis, and mesh stiffness calculation are very difficult. In this study by extracting Napier’s Equations from the tooth profile geometry, geometric parameters of the spherical involute curve have been calculated. The results show that the pitch cone angle has an important effect on the shape of the spherical involute curve, so choosing the correct angle is particularly important. A significant increase in the azimuthal angle is observed by increasing the polar angle. In addition, increasing the angle of the pitch cone reduces the curvature of the side surfaces of the teeth and facilitates the manufacturing process. On the other hand, reducing the pressure angle will result in flat lateral surfaces and a tooth shape similar to the octoidal tooth. The sphere radius variations do not affect the shape of the tooth and only change the size of the tooth. Finally, a gear system comprising a pinion and gear was made from Polylactic Acid (PLA) utilizing the calculated angles to verify the accuracy of computed angles. Also, experimental and finite element methods determined the pinion and gear contact pattern. There was a good agreement between the finite element simulation and the experimental observation. ©2026 The author(s).
Publication Date: 2025
Arabian Journal for Science and Engineering (21914281)50(4)pp. 2663-2689
Parametric study of ductile material forming processes for optimization of damage that occurs in the production stages of the parts will lead to better quality, performance, durability, and reduced production costs. Additionally, implementing an appropriate criterion that accurately predicts and simulates damage growth in the production of a part is an essential step in the optimization process. This research investigates the optimization and minimization of the final damage in a gudgeon pin produced by a two-stage cold extrusion process. First, numerical simulations are performed using the modified Lemaitre’s damage criterion, which provides an accurate estimate of damage growth in combined tensile and compressive loads. In the following, two methods for optimizing the parameters of each extrusion cold die are examined, and the magnitude of the final damage in the product is compared. In the first method, the design of the Taguchi experiment is implemented. In the second method, by implementing and training an artificial neural network and transferring the results to the genetic algorithm, the optimization of the die parameters is investigated to minimize the final damage in the product. A comparison of the results in the two mentioned methods shows that the final damage in the product is less than the critical damage value in both methods. Also, the neural network method will lead to less final damage in the product in comparison with the design method of the Taguchi experiment. © King Fahd University of Petroleum & Minerals 2024.
