Dimensional stability and creep behavior of heat-treated exterior medium density fiberboard


Ayrilmis N. , LAUFENBERG T. L. , WINANDY J. E.

EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS, cilt.67, ss.287-295, 2009 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 67 Konu: 3
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1007/s00107-009-0311-7
  • Dergi Adı: EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS
  • Sayfa Sayıları: ss.287-295

Özet

A series of commercial phenol-formaldehyde bonded MDF panels were exposed to a post-manufacture heat-treatment at various temperatures and durations using a hot press and just enough pressure to ensure firm contact between the panel and the press platens. Physical properties and static flexural strengths of the post heat-treated MDF panels were evaluated according to ASTM D 1037 (2002). The results indicated that the post-manufacture heat-treatment of the exterior MDF panels resulted in improvement of thickness swelling. Water absorption and linear expansion properties were adversely affected by the heat-treatment. Modulus of rupture and modulus of elasticity values of the heat-treated panels decreased with increasing treatment temperature. A series of three 12-week creep tests were performed in climatic chambers conditioned at 65% RH, 90% RH, and cyclic 65-90% RH, all at a steady temperature of 20 A degrees C. The creep tests generally followed procedures as specified in ASTM D 6815-02a (2002). Creep deflections of the panels increased with increasing temperature of the post heat-treatment.