Micro-texturing of polymer surfaces using lasers: a review

Abstract

Micro- and nanoscale structures produced on surfaces of metals, polymers, ceramics, and glasses have many important applications in different fields such as engineering, medical, biological, etc. Laser ablation using ultrashort pulses has become the prominent technique for generating different surface structures for various functional applications. Ultrashort laser ablation proved to be ideal for producing structures with dimensions down to the nanometre scale. In comparison to other texturing techniques employed to create micro/nano features such as electrochemical machining, micro-milling, ion-beam etching, hot embossing, lithography, and mechanical texturing, ultrashort laser ablation produces high-quality surfaces at low cost in a one-step non-contact process. Advantageous characteristics of polymers such as high strength-to-weight ratio, non-corrosive nature, and high electrical and thermal resistance, have made polymers the preferred choice compared to other materials (e.g., steel, aluminium, titanium) in several fields of application. As a result, laser ablation of polymers has been of great interest for many researchers. This paper reviews the current state-of-the art research and recent progress in laser ablation of polymers starting from laser-material interaction, polymer properties influenced by laser, laser texturing methods, and achievable surface functionalities such as adhesion, friction, self-cleaning, and hydrophilicity on commonly used polymeric materials. It also highlights the capabilities and drawbacks of various micro-texturing techniques while identifying texture geometries that can be generated with these techniques. In general, the objective of this work is to present a thorough review on laser ablation and laser surface modification of a variety of industrially used polymers. Since direct laser interference patterning is an emerging area, considerable attention is given to this technique with the aim of forming a basis for follow-up research that could pave the way for potential technological ideas and optimization towards obtaining complex high-resolution features for future novel applications.

Morphological Analysis of Laser Surface Texturing Effect on AISI 430 Stainless Steel

“…In value, the fluence is different, depending on the material. For example, for polymers it is between 0.1 to 1 J/cm 2 , while for inorganic insulators it is between 0.5 and 2.0 J/cm 2 [2]. Related to the present study, Moldovan E. et al [24] showed a decrease in fluence values from 8.49 J/cm 2 to 2.55 J/cm 2 , in the frequency range of 30-100 kHz.…”

“…Laser surface texturing (LST) is a widely used method worldwide for surface functionalization [1][2][3][4], being used in various fields: medical implants [5][6][7][8][9][10][11], wettability tuning [12], optical properties [13,14], hybrid joining [15][16][17], increasing adhesion [18], or cutting tools [19][20][21][22]. The materials that are the object of microtexturing are varied, from dentin and enamel materials, to polymers, ceramics, ferrous and non-ferrous metallic materials, and finally composite materials, in various domains such as engineering, medicine, bioengineering, etc.…”

“…Zhao Y. et al [23] present Si and Cu samples laser ablated with the following characteristics of an X-ray laser: energy 50 µJ, wavelength 46.9 nm, and focused by means of a toroidal mirror at grazing incidence. Two hundred shots were applied to each of the samples, with a power density of ~2 × 10 7 W/cm 2 . The results obtained and the related conclusion that the laser fluence is directly influenced by ablation, is consistent with the results obtained in relation with this research and presented in a previous paper of Moldovan E. et al [24].…”

“…For example, the absorption of energy from a laser beam strongly influences the ablation mechanism. Thus, polymers absorb in a non-linear manner the laser energy compared to metals [2].…”

Laser ablation combined with Nanoimprint Lithography technology as new surface engineering approach to produce novel polymer-based heteronucleants for recalcitrant protein crystallization

“…Not less important in the selection of PC was the fact that this polymer undergoes minimal physico-chemical changes when is subjected to LA and NIL procedures, compared with other patterning technologies such as laser texturing with longer pulses (i.e. nanosecond (ns) and microsecond (μs) pulses), electrochemical machining, micromilling and mechanical texturing [51].…”