Evaluation of moisture content distribution in wood by soft X-ray imaging
- 258 Downloads
A technique for nondestructive evaluation of moisture content distribution in Japanese cedar (sugi) during drying using a newly developed soft X-ray digital microscope was investigated. Radial, tangential, and cross-sectional samples measuring 100 × 100 × 10 mm were cut from green sugi wood. Each sample was dried in several steps in an oven and upon completion of each step, the mass was recorded and a soft X-ray image was taken. The relationship between moisture content and the average grayscale value of the soft X-ray image at each step was linear. In addition, the linear regressions overlapped each other regardless of the sample sections. These results showed that soft X-ray images could accurately estimate the moisture content. Applying this relationship to a small section of each sample, the moisture content distribution was estimated from the image differential between the soft X-ray pictures obtained from the sample in question and the same sample in the oven-dried condition. Moisture content profi les for 10-mm-wide parts at the centers of the samples were also obtained. The shapes of the profiles supported the evaluation method used in this study.
Key wordsNondestructive evaluation Soft X-ray Moisture content distribution Drying Sugi
Unable to display preview. Download preview PDF.
- 4.Davis J, Ilic J, Wells P (1993) Moisture content in drying wood using direct scanning gamma-ray densitometry. Wood Fiber Sci 25:153–162Google Scholar
- 6.Simpson WT (1998) Relationship between speed of sound and moisture content of red oak and hard maple during drying. Wood Fiber Sci 30:405–413Google Scholar