Weathering effects on pendulum hardness, and pull-off adhesion testing of water-based varnish on thermally treated iroko wood
JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY, cilt.1, sa.1, ss.1-12, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 1 Sayı: 1
- Basım Tarihi: 2026
- Doi Numarası: 10.1080/01694243.2026.2675489
- Dergi Adı: JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY
- Derginin Tarandığı İndeksler: Scopus, Science Citation Index Expanded (SCI-EXPANDED), Chemical Abstracts Core, Chimica, Compendex, INSPEC
- Sayfa Sayıları: ss.1-12
- Van Yüzüncü Yıl Üniversitesi Adresli: Evet
Özet
This study evaluated the effects of different weathering durations (168, 336, and 504 h) on surface hardness and adhesion strength of both heat-treated (1.5 h at 190 °C and 2 h at 212 °C) and untreated iroko (Chlorophora excelsa) wood surfaces after application of water-based varnish (WBV). Pendulum hardness (s) and pull-off adhesion (MPa) tests were performed after weathering. According to the results, in the untreated control group, hardness increased from 30 s to 45 s after 504 h of weathering, showing a 48% increase. In the samples treated at 190 °C, hardness increased from 25 s to 41 s after 504 h, showing a 61% increase. The highest increase was observed in the samples treated at 212 °C. Here, the hardness increased from 23 s to 44 s, representing a 91% increase after 504 h of weathering. The highest initial surface adhesion strength (5.30 MPa) was obtained in the unheated samples; however, this value decreased significantly after weathering. Although the initial adhesion strength was lower in the heat-treated samples, those treated at 212 °C for 2 h exhibited more stable weathering performance. The results show that the acceleration of weathering and the application of heat significantly affect the effectiveness of the varnish coating.