Ulay, GokselCakicier, Nevzat2026-07-012026-07-0120260169-42431568-5616https://doi.org/10.1080/01694243.2025.2570405https://hdl.handle.net/20.500.12684/23516In this study, waterborne and solventborne varnishes were applied to the surfaces of ash (Fraxinus angustifolia Vahl.) and iroko (Chlorophora excelsa) woods which were heat treated at 190 degrees C for 1.5 h and 212 degrees C for 2 h according to the thermowood method. The influence of 576 h of aging process on varnish adhesion was determined by pull-off test according to ASTM-D 4541 in UVB-313 EL type aging device. As a result, wood species, varnish type and aging time were found to have a different level of influence on the adhesion strength of varnish layers. The highest adhesion value of 4.804 MPa was obtained in the sample with one-component waterborne varnish applied to ash wood, which was heat treated at 190 degrees C for 1.5 h and aged with UV-B lamp for 144 h.en10.1080/01694243.2025.2570405info:eu-repo/semantics/openAccessAdhesion StrengthArtificial WeatheringHeat TreatmentVarnishWoodArticle406100810212-s2.0-105018829182WOS:001590094400001Q2Q10000-0003-4080-8816