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This work presents an experimental study related to the mechanical performance of a special design spring fabricated with a superelastic shape memory alloy (SMA-SE). For the experimental testing, the spring was coupled in a rotor machine, aiming to attenuate the mechanical vibration when the system went through a natural frequency without any external power source. It was verified that the reduction in instabilities stemmed from the better distribution of vibration force in the proposed device, as well as the damping capacity of the spring material. These findings showed that the application of the M-Shape device of SMA-SE for three different cases could reduce vibration up to 23 dB when compared to the situations without, and with, 1.5 mm of preload. The M-Shape device was shown to be efficient in reducing the mechanical vibration in a rotor system. This was due to the damping capacity of the SMA-SE material, and because the application did not require any external source of energy to generate phase transformation.

Among many rotating machinery vibration sources, there is one due to resonance, when the machine operation frequency crosses the natural frequency region. This study proposes a smart bearing that employs shape memory alloy NiTi helical springs for vibration-level reduction. This smart bearing is capable of dynamically changing its stiffness during machine acceleration or deceleration, keeping its natural frequency far from resonance. Activated by Joule effect and cooled by forced air convection, the prototype installed in horizontal rotating machinery reaches reduction of vibration amplitude of about 63% (root mean square) and 73% (Peak) at critical speed, with response time between 12–15 s. Compared with the results of the reference articles, satisfactory amplitude reduction and better response time were observed.

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The objective of this study is to analyze the possibility of Thermography aid predictive maintenance to detect mechanical failures in rigid a career unshielded ball bearings. Therefore, eight samples were prepared containing various flaws in the tracks of the inner and outer rings of the bearings. Subsequently, each bearing sample was coupled to a bearing with the shaft and motor, positioned on the inertial table. Then the qualitative and quantitative thermography measurement probes associated with the collection of mechanical vibration data were prepared. The results show that it is possible to see the temperature variations associated with mechanical failures introduced compared to records timefrequency vibration spectrum.