Abstract
In this paper, fatigue lifetime prediction models based on time dependent and cycle dependent mechanisms were compared. Their theoretical backgrounds are stress corrosion cracking (SCC) for the former model and dislocation for the latter. The models were fitted to the experimental results with single crystal silicon specimen carried out at different frequencies. The stress-lifetime curves based on SCC theory appeared in two groups of respective testing frequencies. On the other hand, the curves based on dislocation theory were almost identical regardless of frequency. These results suggest that dislocation is more likely mechanism for fatigue rather than SCC.
