Next Article in Journal
Surface Functionalization of Wool via Microbial-Transglutaminase as Bio-Mordant to Improve Dyeability with Madder in the Presence of Alum
Previous Article in Journal
Effects of Process Parameters on Geometrical Characteristics, Microstructure and Tribological Properties of TiB2 Reinforced Inconel 718 Alloy Composite Coatings by Laser Cladding
Open AccessArticle

Surface Properties of Beech Wood after CO2 Laser Engraving

Faculty of Wood Sciences and Technology, Technical University in Zvolen, T.G. Masaryka 24, 960 01 Zvolen, Slovakia
*
Author to whom correspondence should be addressed.
Coatings 2020, 10(1), 77; https://doi.org/10.3390/coatings10010077
Received: 18 December 2019 / Revised: 10 January 2020 / Accepted: 13 January 2020 / Published: 16 January 2020
(This article belongs to the Section Surface Characterization, Deposition and Modification)
The paper deals with the properties of a beech wood surface treated by CO2 laser engraving. The studied concerns were the discoloration, changes to morphology assessed through roughness and waviness parameters, and surface wetting with standard liquids (water and diiodomethane), with the aim of determining the wood surface free energy. The results have confirmed that the studied properties of the beech wood surface varied significantly, which were affected by the laser beam power P and raster density n. With increasing P and n, the lightness L* (expressed in CIE L*a*b* color space) decreased significantly. We also observed significant variation in the color coordinates a* and b*. At 8% laser power, the roughness and waviness parameters measured parallel as well as perpendicular to the grain increased proportionally with the increasing raster density. However, 4% laser power was not associated with distinct changes. Increasing the raster density reduced beech wood surface wetting equally with water and with diiodomethane. This was reflected in the higher contact angle values. The wood surface exhibited higher hydrophobicity at 4% laser power. At this power, the increasing raster density was reflected in the decreasing surface free energy, due to its polar component decrease. At 8% laser power, the changes in surface free energy were very minor from the practical viewpoint. The results suggest a potential good adhesion between film-forming materials and wood. However, the gluing performance may be negatively affected by the high roughness attained at 8% laser power and at higher raster densities.
Keywords: beech wood; CO2 laser; surface properties; color; roughness; wetting; contact angle; surface free energy beech wood; CO2 laser; surface properties; color; roughness; wetting; contact angle; surface free energy
MDPI and ACS Style

Kúdela, J.; Kubovský, I.; Andrejko, M. Surface Properties of Beech Wood after CO2 Laser Engraving. Coatings 2020, 10, 77.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop