Irradiation induced dislocation loop and its influence on the hardening behavior of Fe–Cr alloys by an Fe ion irradiation

Nano indentation analysis and transmission electron microscopy observation were performed to investigate a microstructural evolution and its influence on the hardening behavior in Fe–Cr alloys after an irradiation with 8 MeV Fe4+ ions at room temperature. Nano indentation analysis shows that an irradiation induced hardening is generated more considerably in the Fe–15Cr alloy than in the Fe–5Cr alloy by the ion irradiation. TEM observation reveals a significant population of the a0<1 0 0> dislocation loops in the Fe–15Cr alloy and an agglomeration of the 1/2a0<1 1 1> dislocation loops in the Fe–5Cr alloy. The results indicate that the a0<1 0 0> dislocation loops will act as stronger obstacles to a dislocation motion than 1/2a0<1 1 1> dislocation loops.