Corrosion of materials used as cutting tools of wood

According to the wood species and the type of metallic materials, the wear of woodcutting tools is very different. The metallic nature of cutting tools, the water and water-soluble components in the wood result in an electrochemical mechanism of corrosion. Of course, both a mechanical wear and an electrochemical action are responsible of the total wear of metallic tools. The objective of this study is to characterise the electrochemical action of the wood medium on the corrosion of the woodcutting tool materials. To carry out the corrosion tests, a corrosive medium is obtained by infusing wood shavings into water to obtain a juice of wood. In a second step, we have selected several metallic materials used in woodcutting and a wood specie, namely oak. Electrochemical measurements (R-p, E-corr and i =f(E) curve) were carried out during 24 h in a medium containing a water-soluble extract of oak (=an oak juice). The electrochemical behaviour of each metallic material was characterised and the morphology of the corroded surface was observed by SEM. It is shown that the electrochemical corrosion is not negligible and can be very important on cutting materials. Further experiments are in progress to characterise the effect of the mechanical wear by tribocorrosion measurements. (c) 2006 Elsevier B.V. All rights reserved.