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Components of an automatized transmission system were improved by using techniques of finite element numerical simulation and topology optimization, in order to achieve mass saving and higher performance. Numerical simulations have being applied more frequently during the components design, once the models become more sophisticated, higher computational capacity is available and more precise material properties can be determined. In this paper, a good correlation between the simulation models and the experimental tests was achieved through the material properties determination by means of the impulse excitation technique. This impulse excitation technique consists of a non-destructive test for the dynamic elasticity modulus and material damping through the vibration natural frequencies. The test specimens are evaluated by an impulsive mechanical excitation and the response acoustic signal is collected by a microphone and processed in a conventional computer.

Several projects in engineering involve rotating parts submitted to bending loads, which can result in the material heating. This thermal load happens due to energy loss caused by the material damping. This heat source can be great enough to make the component reach high temperatures and, consequently, risk its performance or even its resistance. A theoretical approach, considering that part of the mechanical energy is converted to thermal energy, implies that the maximum temperature found in a uniform rotary beam is linear dependent with the rotating speed and is directly proportional to the square of the applied load. This work intends to present some results acquired from an experiment performed in a fatigue test machine and also validate the theoretical formulation. Stainless steel (316L) specimens were painted with matte black ink to improve their emissivity. The temperature was measured via a FLIR thermographic infrared camera.