Abstract
The aim of this study was to investigate the effect of nano-silver treatment on some physical and mechanical properties of compressed low density wood species. Wood specimens were prepared from spruce (Picea abies), impregnated with water or nano-silver solution by empty cell process and compressed through radial direction in a hot press. The results showed that by nano-silver treatment, the spring back, bending strength (modulus of rupture) and impact load resistance were improved significantly. The best results for spring-back (0.04%) were seen in the nano-silver impregnated specimens that were compressed at 150°C for 4 hours. The modulus of rupture (MOR), modulus of elasticity (MOE) and impact load resistance in nano-silver impregnated densified specimens were gained for 53%, 41.2% and 175.7%, respectively (in comparison with controls). The maximum amounts of impact load resistance belonged to the nano-silver impregnated specimens which were compressed at press conditions of 150°C for 4 hours, showing the high ability of these specimens against high impact loads such as earthquake loads. An upcoming research (consisting of durability tests) will be done for evaluating the suitability of nano-silver impregnated densified spruce wood for exterior uses.
Zusammenfassung
Ziel dieser Studie war es, den Einfluss einer Imprägnierung mit Nanosilber auf physikalische und mechanische Eigenschaften von Pressholz aus Holzarten mit geringer Dichte zu untersuchen. Aus Fichtenholz (Picea abies) wurden Prüfkörper hergestellt, mit Wasser- oder Nanosilberlösung mittels Leerzellverfahren imprägniert und in radialer Richtung in einer Heißpresse verdichtet. Die Ergebnisse zeigten, dass mittels Nanosilberimprägnierung die Rückverformung, die Biegefestigkeit und die Schlagbiegefestigkeit signifikant verbessert wurden. Die geringste Rückverformung (0,04 %) und die höchste Schlagbiegefestigkeit ergaben sich bei mit Nanosilber imprägnierten Prüfkörpern, die bei 150°C für eine Dauer von 4 Stunden verdichtet wurden. Die Biegefestigkeit von mit Nanosilber imprägnierten Pressholzprüfkörpern nahm im Vergleich zu den Kontrollproben um 53 % zu, der Elastizitätsmodul um 41,2 % und die Schlagbiegefestigkeit um 175,7 %. Dies zeigt das große Potential, das so behandeltes Holz bei hohen Stoßbelastungen, z. B. Erdbebenlasten, hat. Weitere Untersuchungen (Dauerhaftigkeitsprüfungen) sind geplant, um die Eignung von mit Nanosilber imprägniertem Fichtenpressholz für Anwendungen im Außenbereich zu untersuchen.
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The financial support provided by the Shahid Rajaee Teacher Training University is gratefully acknowledged.
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Conflict of interest: Authors (except the 2nd and the last) are academic members of Shahid Rajaee Teacher Training University and have a financial relationship with this organization.
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Rassam, G., Ghofrani, M., Taghiyari, H.R. et al. Mechanical performance and dimensional stability of nano-silver impregnated densified spruce wood. Eur. J. Wood Prod. 70, 595–600 (2012). https://doi.org/10.1007/s00107-011-0590-7
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DOI: https://doi.org/10.1007/s00107-011-0590-7