LIBS New Application: Determination Of Metallic Alloys Surface Hardness

Abstract

Laser Induced Breakdown Spectroscopy (LIBS) is a well known spectrochemical elemental analysis technique. In our investigations of the LIBS spectra it has been found that there is a remarkable correlation between the ionic to atomic spectral lines emission ratio and the surface hardness of solid targets. This phenomenon is related to the repulsive force of the laser induced shockwaves. The present study revealed a confirmation of the above mentioned correlation and the interpretation of the phenomenon in view of the laser induced shockwaves velocity has been also proved experimentally. The relation between the target surface hardness and the ionic to atomic spectral lines intensity ratio of Zr in specially prepared steel alloys treated thermally to have different surface hardness, has been estimated via LIBS. The obtained LIBS spectra have been used to obtain Iionic/Iatomic for certain spectral lines of minor elements in the investigated alloys. The obtained linear relation between the steel samples surface hardness (measured mechanically) and the spectral lines ratio confirm the same effect. The above investigations open the door for LIBS to be exploited not only as a spectrochemical analytical technique but also as an easy way to measure the surface hardness of solid targets.