Infrared laser ablation and atomic emission spectrometry of stainless steel at high temperatures

Abstract

Laser-induced breakdown spectrometry has been evaluated at high temperatures for stainless steel samples. A Q-switched Nd:YAG laser operating at 1064 nm was used to create a microplasma on an AISI 304L stainless steel sample placed inside a laboratory oven. The steel sample was 51.5 cm away from the focusing lens. The temperature of the samples ranged from 25 to 1200 ³C. The plasma light was collected by means of a ®ber optic bundle, spectrally resolved and then detected by a CCD camera. The effects of sample temperature in the formation of a laser-induced plasma have been studied in terms of its spectral features as well as the morphology of the ablated craters in air at atmospheric pressure. A noticeable dependence of signal emission intensity on sample temperature has been found. Depth pro®ling of stainless steel samples for several temperature conditions was performed. Results have revealed changes in the super®cial composition at temperatures above 600 ³C due to the formation of a slag layer of variable thickness, mainly composed of chromium, iron and manganese oxides.

Physics and applications of atmospheric nonlinear optics and filamentation

“…Focusing a laser beam using linear optics is limited to short distances (some tens of meters) because of diffraction [185,186]. Filamentation overcomes this limitation as it provides the equivalent of an "extended focus" over hundreds of meters or more.…”

Damage Profile of HDPE Polymer using Laser-Induced Plasma

“…Because of the characteristic noninvasive nature of LIPS, samples of stainless steel located in a laboratory oven were monitored remotely at different temperatures via fiber optics. In this experiment, LIPS in-depth analyses of the elemental migration caused by the temperature were observed [12]. In recent experiments on an open-path system, LIPS performed measurements remotely, up to 10 meters away from the sample [13].…”

“…These advantages make LIPS particularly useful technique for surface analysis and chemical mapping of bulk solid samples [8,9]. Furthermore, LIPS depth profiles were verified in different matrices, such as thick Zn-coated steel, steels, brass, zinc, foils of iron, and semiconductors [8][9][10][11][12][13]. Because of the characteristic noninvasive nature of LIPS, samples of stainless steel located in a laboratory oven were monitored remotely at different temperatures via fiber optics.…”

In situ analysis of steel melt by double-pulse laser-induced breakdown spectroscopy with a Cassegrain telescope

“…Because the plasma temperatures in the four cases do not vary greatly, the signal enhancement in double-pulse mode is mainly due to increased plasma particle number density under these experimental conditions. A higher ablation rate is reasonably expected when the temperatures of solid steel samples approach their melting points because the thermal mobility of both electrons and atoms is highly enhanced [11,36]. Therefore, the particle density of plasma induced from high-temperature samples should be greatly improved compared with that induced from normaltemperature samples.…”