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Official Journal of the Japan Wood Research Society

Vibrational properties of heat-treated green wood


To investigate the influence of water on heat treatment, green wood was heat-treated. Sitka spruce (Picea sitchensis Carr.) with about 60% moisture content (MC) was used. Young's modulus and loss tangent were measured by the free-free flexural vibration test. The specimens were heated in nitrogen at 160°C for 0.5h. The results were as follows. (1) Recognizing that the effects of heat treatment are mild and that the same specimens cannot be used for both heat treatment and as controls, it was necessary to investigate the effects of the heat treatment based on the variations of properties in the whole of the test lumber. (2) Young's modulus increased and the loss tangent decreased due to heat treatment. When the vibrational properties were measured at various MCs, the MCs at the maximum value of Young's modulus and the minimum value of the loss tangent were lower in heat-treated specimens than in controls. The effects of heat treatment in green wood were similar to those in air-dried wood. (3) The loss tangents of heat-treated specimens were smaller than those of controls at about 0% MC but were larger than those of controls at about 10% MC. We thought that this resulted from the decreased MC at the minimum loss tangent after the heat treatment mentioned above. (4) The properties measured at several MCs were more useful than those at only one moisture content for investigating the effects of heat treatment.


  1. Kubojima Y, Okano T, Ohta M (1998) Vibrational properties of sitka spruce heat treated in nitrogen gas. J Wood Sci 44:73–77

    Article  Google Scholar 

  2. Isogai A, Akishima Y, Onabe F, Usuda M (1991) Structural changes of amorphous cellulose by thermal and hydrothermal treatments. J Soc Fiber Sci Technol Jpn 47:T573-T579

    Google Scholar 

  3. Carrington H (1922) The elastic constants of spruce as influenced by moisture. Aeronaut J 26:462–471

    Google Scholar 

  4. Suzuki M, Nakato K (1963) Effect of water-sorption on dynamic viscoelastic and dielectric properties of heat-treated wood (in Japanese). Mokuzai Gakkaishi 9:211–216

    Google Scholar 

  5. James WL (1961) Internal friction and speed of sound in douglas-fir. For Prod J 11:383–390

    Google Scholar 

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Correspondence to Yoshitaka Kubojima.

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Kubojima, Y., Okano, T. & Ohta, M. Vibrational properties of heat-treated green wood. J Wood Sci 46, 63–67 (2000).

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Key words

  • Green wood
  • Heat treatment
  • Vibrational properties
  • Variation in wood
  • Moisture content