Fatigue behavior experimental results

This paper summarizes the experimental results on the fatigue crack growth resistance of 14 commercial structural alloys tested at selected temperatures between 295 and 4 K. Many of the results are reported here for the first time some data were previously reported [% The comparisons made in this paper lead to generalizations showing that temperature effects on da/dN vs. AAT behavior can be correlated with alloy crystal structure. 

Then the hybrid interference and some design aspects for practical application in (the antomotive steel wheel) have been analyzed. An experimental evaluation of the contributions of the adhesive and the interference to the resultant resistance of the hybrid joint was carried out with particular attention to the phenomena occurring at the interface level and the effect of the adhesive nature, its curing technology and its mechanical response. The outcomes of the laboratory analyses were validated in the steel wheel system. The adhesive contribution mainly affects the static resistance of the hybrid joint, and is strongly related to the type of adhesive exploited. On the other hand, the interference seems to play an important role in the fatigue behavior, especially in the wheel system. 

PRO 97] DROUIN J.M., CALES B., CHEVALIER J. and FANTOZZI G., Fatigue behavior of zirconia hip joint heads experimental results and finite element analysis , J. 

The trend is similar to that discussed on page 345 for short fiber composites, but at the same time it is opposite to the general behavior of plain samples of both short fiber and continuous fiber composites, where the fatigue strength decreases when the biaxiality ratio A2 increases. However, on the basis of the limited amount of data available, it is impossible to justify the experimental evidence and further research is indeed needed to clarify the mechanisms responsible for this peculiar behavior. Results on [0/ 45]2s, [0/ 45/90]s, and [02/ 45]s graphite/epoxy cruciform laminates reported by Jones et al. [16] are less clear than those just discussed—in some cases increasing the biaxiality ratio Ai decreased the fatigue life, and for others the life was increased. 

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