예비압입에 의한 알루미늄 2024-T3 알클래드 합금의 균열성장 지연거동

Crack Growth Retardation Behavior in Aluminium 2024-T3 Alclad Alloy by Pre-Indentation

The effects of pre-indentation technique are presented for A12024-T3 Alclad alloy using as skin material for aircraft fuselage and wing. Indentations were applied to specimens to be placed on the presumed path of fatigue crack growth before fatigue tests. Tension-tension fatigue tests were conducted on the edge cracked specimens in the L-T orientation. Test results were analyzed to investigate the effectiveness of pre-indentation with the variation of specimen's thickness, position of indentation and applied maximum stress. Fatigue crack retardation by pre-indentation is well recognized in the various conditions.