Ultrasound measurement of exterior wood coating thickness
The present paper deals with the measurement of coat thickness on wood using an ultrasonic measurement method. Exterior wood coatings (waterborne acrylate dispersions) with coating film thickness between 80 – 115 µm were examined. The non-destructive film thickness measurement used a Sursonic ultrasound measuring device, enabling measurement of the thickness of thin films on non-ferromagnetic and simultaneously non-conductive materials. The device also enables measurement of very thin layers of coating films, where the transit time of an ultrasound pulse through the film is shorter than the time width of the pulse. The accuracy of measurement using this measuring device was determined; destructive measurement using a light microscope was chosen as a reference measurement method. Differences in the results measured using the destructive and non-destructive methods were recorded; nevertheless, in most cases, these differences are smaller than the uncertainty of measurement using the light microscope. It can be concluded, therefore, that the results of the two compared methods match over the entire range of thickness of 80 – 115 µm. The largest differences in the measurement readings from the destructive and non-destructive methods were identified in the range of 97 – 103 µm.
BOßMANN, F.; PLONKA, G.; PETER, T.; NEMITZ, O.; SCHMITTE, T. 2012. Sparse Deconvolution Methods for Ultrasonic NDT. Journal of Nondestructive Evaluation 31 (3):
BRISCHKE, C.; MEYER, L.; ALFREDSEN, G.; HUMAR, M.; FRANCIS, L.; FLÆTE, P.O.; LARSSON-BRELID, P. 2013. Natural Durability of Timber Exposed Above Ground – a Survey. Drvna Industrija : Znanstveni Časopis Za Pitanja Drvne Tehnologije 64 (2): 113–129.
BURNS, S.E.; ZHANG, M. 2001. Effects of system parameters on the physical characteristics of bubbles produced through air sparging. Environmental Science & Technology 35 (1): 204–208.
CHAUHAN, S.; SETHY, A. 2016. Differences in dynamic modulus of elasticity determined by three vibration methods and their relationship with static modulus of elasticity. Maderas-Cienc Tecnol 18 (2): 373-382.
CRILLY, P.B. 1991. A quantitative evaluation of various iterative deconvolution algorithms. IEEE Transactions on Instrumentation and Measurement 40 (3): 558–562.
DE MOURA, L.F.; HERNANDEZ, R.E. 2006. Evaluation of varnish coating performance for three surfacing methods on sugar maple wood. Forest Products Journal 56 (11/12): 130.
DEMIRLI, R.; SANIIE, J. 2001. Model-based estimation of ultrasonic echoes. Part II: Nondestructive evaluation applications. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control 48 (3): 803–811.
EATON, R.A.; HALE, M.D.C. 1993. Wood: Decay, pests, and protection. (1st ed). London: Chapman & Hall.
EN 335. 1992. Durability of wood and wood-based products. Definition of hazard classes of biological attack. Brussels: European Committee for Standardization.
EN 927. 2013. Paints and varnishes – Coating materials and coating systems for exterior wood.
Brussels: European Committee for Standardization. EN ISO 2808. 2007. Paints and varnishes – Determination of film thickness. Brussels: European Committee for Standardization.
EVANS, P.D. 2008. Weathering and Photoprotection of Wood. In Development of Commercial Wood Preservatives (Roč. 982, s. 69–117). American Chemical Society.
EVANS, P.D.; HAASE, J.G.; SEMAN, A.S.B.M.; KIGUCHI, M. 2015. The Search for Durable Exterior Clear Coatings for Wood. Coatings 5 (4): 830–864.
FEIST, W. C. 1990. Outdoor wood weathering and protection. In Advanced in Chemistry Series No. 225. Washington, DC: American Chemical Society. 263–298. Chapter 11.
GAYLARDE, C.C.; MORTON, L.H.G.; LOH, K.; SHIRAKAWA, M.A. 2011. Biodeterioration of external architectural paint films – A review. International Biodeterioration & Biodegradation 65 1189–1198.
GÖRGÜN, H.V.; DÜNDAR, T. 2018. Strength grading of turkish black pine structural timber by visual evaluation and nondestructive testing. Maderas-Cienc Tecnol 20(1):56-64.
GRÜLL, G.; FORSTHUBER, B.; TSCHERNE, F.; SPITALER, I. 2014. Weathering indicator for artificial and natural weathering of wood coatings. European Journal of Wood and Wood Products 72 (5): 681–684.
GRÜLL, G.; TRUSKALLER, M.; PODGORSKI, L.; BOLLMUS, S.; TSCHERNE, F. 2011. Maintenance procedures and definition of limit states for exterior wood coatings. European Journal of Wood and Wood Products 69 (3): 443–450.
HILL, C.A.S. 2006. Wood modification: chemical, thermal and other processes. Chichester, England; Hoboken, NJ: John Wiley & Sons.
HORA, G.; BELZ, A. 1998. Measuring commercial layer-thickness on wood with an ultrasonic unit. Paint & Coatings Industry 14 (11): 62–66.
MAMOŇOVÁ, M.; REINPRECHT, L. 2008. Structure and color of acrylate coatings after outer and inner 1-yearlong exposition. In Interaction of Wood with Various Forms of Energy. Technical University in Zvolen – Slovakia 91–97.
MASARYKOVÁ, M.; PÁNEK, M.; REINPRECHT, L. 2010. Micro-structural analysis of coatings with nanoscale particles after ageing in Xenotest. In Wood Structure and Properties. Technical University in Zvolen – Slovakia 209-216.
MEIJER, M.DE; THURICH, K.; MILITZ, H. 1998. Comparative study on penetration characteristics of modern wood coatings. Wood Science and Technology 32 (5): 347–365.
MEIJER, M. DE; THURICH, K.; MILITZ, H. 2001. Quantitative measurements of capillary coating penetration in relation to wood and coating properties. European Journal of Wood and Wood Products 59 (1): 35–45.
MONTERO, M. J.; DE LA MATA, J.; ESTEBAN, M.; HERMOSO, E. 2015. Influence of moisture content on the wave velocity to estimate the mechanical properties of large cross-section pieces for structural use of Scots pine from Spain. Maderas-Cienc Tecnol 17 (2): 407-420.
MOYA, R.; RODRÍGUEZ-ZÚÑIGA, A.; VEGA-BAUDRIT, J.; PUENTE-URBINA, A. 2017. Effects of adding TiO2 nanoparticles to a water-based varnish for wood applied to nine tropical woods of Costa Rica exposed to natural and accelerated weathering. Journal of Coatings Technology and Research 14 (1): 141–152.
REINPRECHT, L. 2016. Wood Deterioration, Protection and Maintenance. John Wiley & Sons.
SCHMIDT, O. 2006. Wood and Tree Fungi: Biology, Damage, Protection, and Use. Springer Science & Business Media.
SINGH, A.P.; DAWSON, B.S. 2004. Confocal microscope—A valuable tool for examining wood-coating interface. Journal of Coatings Technology and Research 1 (3): 235–237.
SINGH, A.P.; DAWSON, B.S.W. 2006. Microscopic assessment of the effect of saw-textured Pinus radiata plywood surface on the distribution of a film-forming acrylic stain. Journal of Coatings Technology and Research 3 (3): 193.
SINGH, A.P.; RATZ, A.; DAWSON, B.S. 2007. A novel method for high-resolution imaging of coating distribution within a rough-textured plywood surface. Journal of Coatings Technology and Research 4 (2): 207–210.
SVILAINIS, L.; LUKOSEVICIUTE, K. ; LIAUKONIS, D. 2017. Reiterative deconvolution: New technique for time of flight estimation errors reduction in case of close proximity of two reflections. Ultrasonics 76: 154–165.
VALVERDE, J.C.; MOYA, R. 2014. Correlation and modeling between color variation and quality of the surface between accelerated and natural tropical weathering in Acacia mangium, Cedrela odorata and Tectona grandis wood with two coating. Color Research & Application 39 (5): 519–529.
WILLIAMS, S.R. 2005. Weathering of Wood. In Handbook of Wood Chemistry and Wood Composites. CRC Press.
WILLIAMS, S.R. 2010. Finishing of Wood. In Wood Handbook. General Technical Report FPL-GTR-190. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory: 16-1 - 16-39. Chapter 16.