Measurement and Analysis of Three-Dimensional Surface Topography of Sawn Timber Based on Scanning Probe Method

Abstract

In order to explore the characteristics of the three-dimensional surface morphology of sawn timber, a threedimensional wood surface morphology tester based on the scanning probe method and the principle of atomic force microscope was used to test the three-dimensional surface morphology of three kinds of sawn timber and calculate its surface roughness. This study also analyzed the reasonable plan for the value of wood surface roughness and the advantages of the three-dimensional shape tester, as well as the influence of tree species, three sections, air-dry density and other factors on the surface roughness of the specimen after mechanical processing. The results have shown that it is a more appropriate method to select the calculated values of Sa and Sq as the evaluation of the surface roughness of wood with random surface characteristics. The three-dimensional wood surface topography tester can efficiently, conveniently and accurately display the three-dimensional topography of wood at a micron-level resolution, and is characterized by high efficiency and good durability. The three-dimensional surface morphology characteristics of the three sawn woods correspond to their roughness. The surface roughness of woods is arranged as follows: Sitka spruce > Larch > Beech. For the same tree species, the roughness of the corresponding section after sawing is as follows: chordwise section > crosswise section > radial section. The radial section has lower roughness than the other surfaces. The surface roughness of the wood after sawing is mainly related to its air-dry density. The above is intended to provide a useful reference for the application of measuring and evaluating the surface roughness of sawn timber using the three-dimensional surface topography test method.