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The research is dedicated to determine one of the most important mechanical properties which is the Young's modulus. Its value is crucial for clearly explaining and understanding the results of any mechanical loading experiment. Three cylindrical samples of 15 mm height and 7.5 mm diameter were designed using SpaceClaim application in the ANSYS Software and then 3D printed using Direct Metal Laser Sintering via EOS M 290 3D printer. The specimens were then tested under compression in order to determine the value of the Young's modulus for titanium alloy of grade 23 (Ti, Al, V, O, N, C, H, Fe, Y). The finite element method was executed using ANSYS mechanical to run a comparison between laboratory results with nominal results of the Young's modulus. Young's modulus value is affected by the 3D printing accuracy and quality, the material's quality as well; however, the deviation is within 10%.

Over the recent years metallic foams have become a popular material due to their unique characteristics like low density coupled with beneficial mechanical properties such as good energy absorption, heat resistance, flame resistance, etc. However, their production processes (foaming) is highly stochastic which results in an inhomogeneous foam structure. Hybrid aluminum foam with closed-cell has been manufactured using direct foaming method coupled with the Taguchi Design of Experiments (DOE). Image analysis has been carried out to determine the average porous area and pore size. The influence of the production parameters (amount of foaming agent added, mixing speed and temperature) on the pore size and the porous area has been analyzed using the statistical Taguchi technique. From the experiments it was seen that the most important control factor for both the pore size and the porous area is the amount of the foaming agent added, followed by temperature and stirring speed. Furthermore, the statistical significance of these manufacturing parameters on the response was also investigated by performing analysis of variance (ANOVA) statistical method.

Nowadays, vehicles with alternative drives are playing an increasingly important role in road transport. Among the various types of alternative-drives, the most widespread ones are hybrid and electric ones, thanks for the rapid development of modern batteries, and hybrid and electrical systems. The above fact establishes the importance of research on various types of electric motors. The Faculty of Engineering of the University of Debrecen has more than a decade of experience in developing prototype race cars with pneumatic and electric drive. For the more effective and conscious development and racing a simulation program has been developed in MATLAB/Simulink environment for the computation of the dynamic functions of a vehicle moving in a linear path. The program is characterized by a modular structure, so the different structural units (vehicle body, front and rear wheels, power train, motor) are modelled and simulated separately. In this study we present models and simulation programs for different electric motor types (series-wound DC and brushless DC motors) in MATLAB/Simulink and apply them in our vehicle dynamics simulation program. From the simulation results the performance of a vehicle – driven by an electric motor – can be predicted in a race situation, consequently the most suitable motor with the optimal characteristics can be selected to it.

The development of an efficient procedure for 3d modeling and finite element simulation of metal foams is one of the greatest challenges for engineer researchers nowadays. Creating 3d CAD model is alone a demanding engineering task due to its extremely complex geometry, and the proper finite element analysis process is still in the center of the research. The increasingly widespread application of the metal foams, e.g. in vehicle and medical industry, requires this knowledge in the design phase. A closed-cell metal foam is studied using different analyzing methods where the aim is to collect information about the composition and geometry (structure) that is satisfactory for the later research. Using statistical methods microscopic, X-ray and surface analyzing studies on the specimens produced according to the concerning standard are evaluated. The main goal of this part of the project is to obtain structural information and to determine the homogeneity or the in-homogeneity property of the metal foam specimens taken from different locations.

This paper presents a novel solution for shape optimization of compressed rubber parts. The procedure is based on the finite element method (FEM). A special purpose FEM code written in FORTRAN has been developed for the analysis of nearly incompressible axi-symmetric rubber parts. Numerical stability of the code and sensitivity analysis of the FEM input parameters are investigated. The aim of the parameter optimization is to reduce the time consuming FEM computations for the optimization process. The objective of the optimization is to find the optimal shape of the investigated rubber parts with a specified load-displacement curve. A regression model is used to determine the connection between the input and output data calculated by the FEM.

This paper deals with the main principles of shape optimization of elastomers. The aim of the research is how to find the right optimizing solutions which can handle rubber components used in vehicle industry. Further on the chosen solution algorithms will be built in the developed finite element code.