Laser-Treated Steel Surfaces Gliding on Snow at Different Temperatures

Abstract

With the goal of substituting a hard metallic material for the soft Ultra High Molecular Weight Polyethylene (UHMWPE) presently used to make the bases of skis for alpine skiing, we used two non-thermodynamic equilibrium surface treatments with ultra-short (7–8 ps) laser pulses to modify the surface of square plates (50 × 50 mm2) made of austenitic stainless steel AISI 301H. By irradiating with linearly polarized pulses, we obtained Laser Induced Periodic Surface Structures (LIPSS). By laser machining, we produced a laser engraving on the surface. Both treatments produce a surface pattern parallel to one side of the sample. For both treatments, we measured with a dedicated snow tribometer the friction coefficient µ on compacted snow at different temperatures (−10 °C; −5 °C; −3 °C) for a gliding speed range between 1 and 6.1 ms−1. We compared the obtained µ values with those of untreated AISI 301H plates and of stone grinded, waxed UHMWPE plates. At the highest temperature (−3 °C), near the snow melting point, untreated AISI 301H shows the largest µ value (0.09), much higher than that of UHMWPE (0.04). Laser treatments on AISI 301H gave lower µ values approaching UHMWPE. We studied how the surface pattern disposition, with respect to the gliding direction of the sample on snow, affects the µ trend. For LIPSS with pattern, orientation perpendicular to the gliding direction on snow µ (0.05) is comparable with that of UHMWPE. We performed field tests on snow at high temperature (from −0.5 to 0 °C) using full-size skis equipped with bases made of the same materials used for the laboratory tests. We observed a moderate difference in performance between the untreated and the LIPSS treated bases; both performed worse than UHMWPE. Waxing improved the performance of all bases, especially LIPSS treated.

Advances in Plasma and Laser Engineering

“…The series of articles presented in this Special Issue covers the laser processing of steel and silicon, as well as laser drilling and welding. Maggiore et al,in [12], presented the use of two non-thermodynamic equilibrium surface treatment methods with ultrashort laser pulses to modify the surface of square plates made of austenitic stainless steel. Kovalev et al,in [13], discussed different methods for producing light-trapping "black" silicon, namely laser, chemical and hybrid chemical/laser.…”

Wetting Behavior Driven by Surface Morphology Changes Induced by Picosecond Laser Texturing

“…Laser-textured shape and textured area fraction have a strong influence on the wetting behavior and bacterial adhesion of metallic (Ti-6Al-4V), ceramic (hydroxyapatite), and polymeric (polymethyl methacrylate) surfaces, all of which are relevant for biomedical, energy, and mechanical applications. Surface micro-texturing has been broadly applied to improve tribological properties, such as friction behavior and anti-wear [7]. Laser processing is also used to fabricate micro-/nanostructures, achieving some specified functions, such as colorization and superhydrophobicity.…”