Fabrication of micro-features on 304 stainless steel (SS-304) using Nd:YAG laser beam micro-machining

Abstract

In the present study, micro-channels and micro-dimples are fabricated with different dimensions on the surface of SS-304 alloy by pulsed Nd:YAG laser beam micro-machining. The effect of various laser parameters on the machining performance characteristics is evaluated. The effect of process parameters viz. laser scanning speed, current, laser pulse frequency and pulse duration are studied using argon gas. The width or diameter and depth of micro-features are considered as the output responses. 3D laser surface profilometer is used to study and measure the dimensions of fabricated micro-features. The results showed that the selection of micro-feature size is critical to achieve desired machining results. All the processing parameters have noticeable effect on the geometry and quality of micro-features. The dimensions (diameter, width and depth) of micro-features are decreased with higher scanning speed and increased with increase in pulse frequency, pulse duration as well as current. The appropriate combination of parameters can yield the better results for quality and size of micro-features. Lower scanning speed with higher pulse frequency with a proper set of current and pulse duration can be used in order to fabricate micro-channel, whereas higher scanning speed and lower pulse frequency can be used to obtain micro-dimples.