This paper will discuss two different techniques to measure mechanical properties of thin film, bulge test and nano-indentation test. In the bulge test, uniform pressure applies to one side of thin film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as the elastic modulus and the residual stress. Nano-indentation measurements are accomplished by pushing the indenter tip into a sample and then withdrawing it, recording the force required as a function of position. . In this study, modified King’s model can be used to estimate the mechanical properties of the thin film in order to avoid the effect of substrates. Both techniques can be used to determine Young’s modulus or Poisson’s ratio, but in both cases knowledge of the other variables is needed. However, the mathematical relationship between the modulus and Poisson's ratio is different for the two experimental techniques. Hence, achieving agreement between the techniques means that the modulus and Poisson’s ratio and Young’s modulus of thin films can be determined with no a priori knowledge of either.

Rollers are used widely in the transfer of the steel plate in steel mills. This method causes very loud impact noise because of the deflection of the steel plate and causes noise pollution in the labor environment. In this paper, the relationship between the impact noise and the impact force was examined. Also, a method for reducing the impact force was implemented in order to reduce the impact noise. The noise index was introduced to quantify the relation between impact noise and impact force. Dynamic and impact analyses were carried out using the finite element method. Experiments on impact were also carried out in order to validate the results. KEY WORDS: deflection; impact noise; impact force; noise index; finite element method.