This study investigates the fatigue degradation and crack propagation in the locking mechanism of PET bottle blow molding machines, focusing on the impact of elliptical cracks on the mechanism’s performance and longevity. The locking mechanism, which plays a vital role in securing the mold during the blow molding process, is subjected to repeated loading, making it susceptible to fatigue damage. Using a combination of finite element analysis (FEA) and experimental methodologies, we examine the stress distribution, deformation, and displacement in the mechanism under operational loads. The study identifies the most stressed component and models the behavior of an elliptical crack located at the center of this component. A stress intensity factor (K) of 3.7553 MPa.mm-0.5 is found, indicating significant risk in the crack region. Fatigue analysis using Goodman’s law predicts a service life of one million cycles with a safety factor of 2.08. These findings highlight the need for targeted design and maintenance strategies to enhance the reliability and durability of PET blow molding machines.

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

This work is a study of the elastic fields’ effect (stresses and displacements) caused by dislocations networks at a heterostructure interface of a InAs / GaAs semiconductors thin system in the cases of isotropic and anisotropic elasticity. The numerical study of this type of heterostructure aims to predict the behavior of the interface with respect to these elastic fields satisfying the boundary conditions. The method used is based on a development in Fourier series. The deformation near the dislocation is greater than the other locations far from the dislocation.     

In the present work, (Cu-Sn, Cu-Co) based alloys with different compositions have been obtained by using powder metallurgy (PM). These alloys were created with the purpose of increasing mechanical and structural properties of the industrial parts. The compacts are made according to the sintering manufacturing method, the uniaxial compressed cold samples. Metallographic characterizations, hardness and density measurements were carried out in order to study the influence of the addition of tin and cobalt, the variation of the compaction pressure and the sintering temperature on the finishing product. It has been proved that the addition of tin and cobalt to a copper powder mixture increase the properties of the sintered parts.

In the present work, (Cu-Sn, Cu-Co) based alloys with different compositions have been obtained by using powder metallurgy (PM). These alloys were created with the purpose of increasing mechanical and structural properties of the industrial parts. The compacts are made according to the sintering manufacturing method, the uniaxial compressed cold samples. Metallographic characterizations, hardness and density measurements were carried out in order to study the influence of the addition of tin and cobalt, the variation of the compaction pressure and the sintering temperature on the finishing product. It has been proved that the addition of tin and cobalt to a copper powder mixture increase the properties of the sintered parts.