Short fatigue crack growth in an artificial-defect-containing nanostructured bainitic steel

For a full exploitation of novel steels in applications under mechanical cyclic loading, it is vital to understand the crack-microstructure interactions. In this work, the fatigue behaviour of a nanostructured bainitic steel in the short crack regime has been studied considering the structural integrity of the material and its polycrystalline nature. For that purpose, a specimen containing an artificial defect has been designed and manufactured, sub-jected to interrupted fatigue testing, and examined by crystallography-sensitive techniques. Results show that, depending on the loading conditions, different crystallographic boundaries can play an important role in the crack path and crack growth rate.

Automated summary

This study investigates the importance of crack-microstructure interactions in the fatigue behavior of nanostructured bainitic steel in the short crack regime. Results show that different crystallographic boundaries play a significant role in the crack path and growth rate, depending on the loading conditions.