In-situ TEM investigation of dislocation loop evolution in Al-forming austenitic stainless steels during Fe+ irradiation: Effects of irradiation dose and pre-existing dislocations

•In-situ irradiation behavior of AFA stainless steel in TEM was studied for the first time.•Effect of dislocation lines on loop evolution in AFA stainless steel was first researched.•Both Frank loops with b = 1/3<111> and perfect loops with b = 1/2<110> were formed.•Loop size vs. dose and loop density vs. dose in AFA stainless steel were established.•Total damage and hardness increment as a function of dose were obtained.