Depth profiling of tungsten coating layer on CuCrZr alloy using LIBS approach

Abstract

Laser induced breakdown spectroscopy (LIBS) was employed to find the depth profile of W‐coated CuCrZr alloy. Cathodic arc deposition method was applied to produce tungsten coating on the CuCrZr alloy. The LIBS measurements were carried out by using a Nd:YAG laser at its fundamental wavelength (1064 nm) with various fluences. The spectral intensity emitted from laser induced plasma of the coating material was investigated for both elemental and depth‐profile analyses in terms of linear correlation coefficient. Other surface characterization techniques (scanning electron microscopy and energy dispersive X‐ray) were also used to determine morphology and elemental composition. It is observed that nonuniform radial energy distribution of Gaussian laser beam caused gradual decay of spectral lines of the coating and rise of substrate lines. The results indicate that the spectral intensity from W coating was higher than that from the bulk material at same laser fluence. The high‐resolution in‐depth profile was achieved at low fluence. This study demonstrates that LIBS is a promising technique for the depth‐profiling analysis of W coating of EAST‐like material and can be used to determine the material erosion and impurity deposition on plasma facing components.