Controlling surface topography using pulsed laser micro structuring

There is significant interest in controlling surface topography on metal parts including smoothing rough or wavy surfaces, adding aesthetic features, and creating functional structures. Pulsed laser micro structuring (PLμS) dynamically manipulates each pulse fluence during laser remelting to create a net, mass-neutral, lateral displacement of material several times greater than the melt pool diameter. This paper presents experimental investigations into specific process capabilities, example applications, and a novel phenomenological theory. The paper demonstrates how the resultant process can attenuate high-spatial-frequency roughness, correct mid-spatial-frequency error (i.e., waviness), and create desirable surface topography with a single laser system.