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The study is carried out through numerical and experimental methods. The finite element method is used to simulate the support mechanical behavior via modal analysis, and for the evaluation of stress concentration regions through pressure and thermoelastic static analyses, and dynamic analysis. The fatigue life is calculated for the presented stresses. Stress, acceleration and temperature data were obtained through dynamic test. For material evaluation, chemical analysis, hardness and metallographic analysis were carried out. For thoroughness, a failed support fractography will be presented. The objective of this study is to correlate the data obtained by numerical method with experimental data, and as a result, the support failure mechanism was identified. A modified support is presented to avoid the failure for the determined loads. The support within the proposed modifications reduces the current maximum stress in 41% and improved the fatigue life in 4.99e5 cycles.

The tempering effect on as-quenched compressive residual stress of commercial carburized samples is the main objective of this work. The compressive residual stress developed during the quenching process of carburized parts is fairly well known. The study was performed using SAE 4120 RH steel samples with two different diameters of 15 and 38 mm, which resulted in different cooling rates, with a direct effect on the core microstructure. The carburized surface microstructures were considered similar. The smaller diameter core microstructures were predominantly martensitic however bainitic in the larger bars samples. The as-quenched surface compressive residual stress was lower in the smaller diameter samples. The 15 mm diameter samples showed two different types of behavior, i.e., the compressive stress for lower temperatures during tempering process was reduced, whereas the values were increased at higher temperatures.