Parameter interactions in two-block welding and the wood nail concept in wood dowel welding

Thermo-hydro and thermo-hydro-mechanical wood processing: An opportunity for future environmentally friendly wood products

“…Some of the research results are given by Gfeller et al (2003), Pizzi et al (2004), Leban et al (2004Leban et al ( , 2005, Ganne-Chédeville et al (2005, 2006a,b, 2007, Stamm (2005), Stamm et al (2005a,b,c), , Stamm et al (2006). Most of the wood welded by friction is Norway spruce (Picea abies (L.) Karst.)…”

“…They concluded that reactions between furfural and other furan derivatives with lignin are the main reactions in the friction zone leading to cross-linking of the 'melted' contact material. This material has also been examined by Gfeller et al (2004), Ganne-Chédeville et al (2005) and Kanazawa et al (2005) and it has been shown that the essential chemical modifications involving the polymeric constituents of wood in friction welding occur in the first five to six seconds and that they slow down or even stop afterwards. Analysis by FTIR and CP-MAS 13 C NMR of the welded area of wood has shown dehydration and an apparent increase in the crystallinity of the cellulose.…”

“…After six seconds of welding, the wood begins to carbonize, and an increase in cross-linking of the lignin network is observed. Ganne-Chédeville et al (2005) have suggested that to produce the frictional energy necessary for the reaction between furfural and other furan derivatives with lignin and to achive good adhesion between the two wood pieces, the variation in temperature at the interface has to be monitored (Ganne-Chédeville et al 2006a,b). During the welding process, the interface of the wood heats up and creates a 'melted' material.…”

Parameters of wood welding: A study with infrared thermography

“…In the tangential direction, this ratio is lower than in the radial direction. It was previously demonstrated that in the case of rotational wood-dowel welding, interfacial densification is greater in regions where the wood had a higher density (Ganne-Ché deville et al 2005). In linear vibration welding, the phenomenon might be similar, which means that at lower wood density the resistance of the joint is also lower.…”

Influence of the moisture content on the fracture characteristics of welded wood joint. Part 1: Mode I fracture

“…The adhesion is generated in the interface from the thin layer of molten wood substances after solidification (Gfeller et al 2003). The mechanical performance of the process is frequently investigated by varying the parameters, such as welding time and pressure, amplitude of vibration, and surface quality, and by submitting the welded specimens to shear test according to DIN-EN (2003) 205 (Gfeller et al 2003(Gfeller et al , 2004Ganne-Chédeville et al 2005;Ganne-Chédeville 2008). Ganne-Chédeville et al (2008) observed the behavior of double cantilever beam (DCB) specimens and measured the critical energy release rate (G Ic ) of a welded joint.…”