Effects of Laser Texturing on Technical Surfaces

Abstract

Different laser beam techniques were applied to AISI M3 steel samples in order to produce well-defined surface microtextures consisting of pores, which can act as lubricant pockets (reservoir) as well as traps for wear debris. Both effects contribute to improve the tribological performance of textured functional surfaces. The tribological performance of lasertetxures was studied as function of the pore depth and diameter in unidirectional sliding tests under starved lubrication. The lasertetxured surfaces tested under those conditions were produced by a well-established ns laser technique using a Q switched Nd:YAG laser. The topographical microstructures of these laser-induced textures were characterized by optical and scanning electron microscopy as well as replica technique. A significant change in friction behavior as compared to untextured tool surfaces was observed when using microtextured surfaces.In another part of the study, the influence of new-developed fs laser technique of the tool steel was investigated. The fs laser texturing of the steel results in a change of the metallographic structure of the laser-affected zone, which is clearly detectable in cross-section samples. The structure of the material and chemical composition of the laser-affected, pore-near region was analyzed by transmission electron microscopy with combined EDX analysis. It could be shown that the laser-affected zone seems to consist of an amorphous or nanocrystalline material in opposite to the ‘macrocrystalline’ steel substrate. Nanoindentations revealed a two times higher hardness of the laser-affected zone than the steel bulk phase.

Femtosecond laser processing of nitride-based thin films to improve their tribological performance

“…Previous investigations [3,15] under mixed lubrication conditions have indicated that suitable pore diameters should be smaller than 50 µm with aspect ratios between 1 : 2 and 1 : 1. Comparing these values with typical film thicknesses, pore depths are in most cases larger than film thicknesses.…”

“…Laser micropatterning of functional surfaces using nanosecond pulses has been demonstrated [1][2][3][4][5][6] to improve their tribological performance, leading to increased lifetimes of the tribological systems in which they are used. Arrays of pores obtained by laser micromachining can act as lubricant reservoirs, capable of feeding the lubricant directly into the contact zone of the sliding surfaces.…”

Laser Texturing for Superwetting Titanium Alloy and Investigation of Its Erosion Resistance

“…For example, by texturing the titanium (Ti) alloy surface, some key surface properties, including wettability and hardness, can be effectively modified and controlled, indicating the superior advantage of surface texturing techniques [17][18][19]. So far, many surface texturing techniques have been developed and utilized by academia and industries [20], and the most widely used techniques include Vibrorolling technique [21,22], UV-LIGA technique [23], deep reactive ion etching [24][25][26], surface peening [27] and laser surface texturing [28][29][30][31][32][33][34][35][36][37]. Among these surface texturing techniques, laser surface texturing has received considerable attention due to some distinct advantages such as flexibility, high precision, low cost, high processing efficiency and ease for industrial automation [38].…”

Evolution of the True Contact Area of Laser Textured Tungsten Under Dry Sliding Conditions

“…Both the friction coefficient and wear can be influenced by changing the topography of the surface. Therefore, there are many well-known methods for modifying surfaces (Willis, 1986;Gerbig et al, 2002;Li et al, 2010).…”