Thermodynamic Analysis and Experimental Study of Masked Corrosion Protection of 304 Stainless Steel Processed with Nanosecond Pulsed Laser

Abstract

A three-dimensional finite element model of nanosecond pulsed laser processing is developed, given the variation of thermal physical parameters with temperature during the laser processing of metallic materials. The effect of process parameters on the temperature field is analyzed by simulating the temperature field of 304 stainless steel processed by nanosecond lasers. Temperature is the most sensitive to repetition frequency. The effects of power, spot diameter, scanning speed, and scan line spacing on temperature decrease successively. The quantitative analysis of the relationship between processing parameters and temperature provides a basis for the corrosion-resistant mask processing parameters on the surface of 304 stainless steel. The applicable laser processing parameters are given according to the results of the orthogonal simulation experiments; the masks and experimental studies on corrosion resistance are carried out. Experimental results show that the corrosion potential of the mask increased by a maximum of 326 mV and the corrosion current decreased by a maximum of 479 nA/cm2 in the passivation electrolyte. Localized electrolysis of the material surface is carried out using the mask provided by the corrosion-resistant surface, and thus the micro-patterns of more complex shapes are processed. This study offers a new path for the micro electrolytic processing mask process.