Investigation of the Impact of Micro-Structuring on the Bonding Performance of Beechwood (Fagus Sylvatica L.)
2022 (English)In: Forests, E-ISSN 1999-4907, Vol. 13, no 1, article id 113
Article in journal (Refereed) Published
Abstract [en]
Although glueing softwood is well mastered by the industry, predicting and controlling bond quality for hardwood is still challenging after years of research. Parameters such as the adhesive type, resin–hardener ratio, and the penetration behaviour of the wood are determinants for the bond quality. The aim of this work was to assess to what extent the glueing behaviour of beechwood can be improved by using structural planing. The different surfacing methods were characterised by their roughness. The bond strength of the micro-structured surfaces was determined according to EN 302-1, and the delamination resistance was tested as indicated by EN 302-2 for type I adhesives. Micro-structured surfaces were compared with different surfaces (generated by surfacing methods such as dull/sharp planing and sanding). In dry test conditions, all surfacing methods gave satisfying results. In the wet stage, the bond strength on the finer micro-structured surface slightly outperformed the coarse structure surface. For the delamination resistance, a clear improvement could be observed for melamine-formaldehyde-bonded specimens since, when using the recommended amount of adhesive, micro-structured surfaces fulfilled the requirements. Nevertheless, structural planing cannot lead to a reduction in the applied grammage since no sample with a smaller amount fulfilled EN 302-2 requirements even by observing the recommended closed assembly waiting time. Adhesion area enlargement of the micro-structuring is minor. The good delamination performance without waiting time (CAT) is not caused by surface enlargement, since finer micro-structured surface with negligible area increase and delivered even better delamination resistance. Subsurface analysis should be carried out to thoroughly investigate this phenomenon.
Place, publisher, year, edition, pages
MDPI, 2022. Vol. 13, no 1, article id 113
Keywords [en]
Hardwood bonding, Machining method, Micro-structured, Planing, Roughness, Sanding, Structural planing, Surfacing method
National Category
Wood Science
Research subject
Wood Science and Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-89023DOI: 10.3390/f13010113ISI: 000747636500001Scopus ID: 2-s2.0-85123194661OAI: oai:DiVA.org:ltu-89023DiVA, id: diva2:1642482
Note
Validerad;2022;Nivå 2;2022-03-07 (johcin)
2022-03-072022-03-072024-07-04Bibliographically approved