Application of thin layer activation technique to study surface erosion of D9 stainless steel during laser ablation process

The thin layer activation (TLA) technique has been applied to study the surface erosion of D9 stainless steel (D9 SS) by producing a thin layer (~430 µm) of 56Co activity using 15 MeV proton beam. The cumulative ablation thickness of 90 µm in D9 SS, observed against total deposited laser energy of ~20 kJ, is reported here. The minimum detection limit was found to be ~50 nm in the measurement of surface loss of material by TLA technique. No surface loss could be detected when D9 SS was exposed to laser fluence pre-requisite for its efficient decontamination.