Laser ultrasonic Evaluation of 316L Corrosion Resistance Based on the Influence of Grain Size

Abstract

Several 316L samples with different grain size and distribution were conducted with different heat treatments, and then each samples were measured by scanning electron microscope(SEM), Laser ultrasonic, and Electrochemistry. Longitudinal wave echoes were used to calculate the attenuation of ultrasound after wavelet transform. The results show that the average grain size will affect the corrosion resistance of the sample, and the attenuation of ultrasonic waves has a high sensitivity to the average grain size. Finally, a laser ultrasonic evaluation method for 316L corrosion resistance based on the influence of mean grain size on corrosion resistance is proposed, and it is a nondestructive testing method which could be used in online testing.