Surface changes in wood submitted to thermomechanical densification


  • Douglas Edson Carvalho Universidade Federal do Sul da Bahia. Centro de Formação em Ciências Agroflorestais. Ilhéus
  • Márcio Pereira da Rocha Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba, Paraná, Brasil
  • Ricardo Jorge Klitzke Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba, Paraná, Brasil
  • Pedro Henrique Gonzalez de Cademartori Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba



Surface roughness, densification, hydrophobicity, thermos-mechanical treatment, wettability, wood chemistry, wood morphology


Ideal thermomechanical treatment conditions that reduce roughness and increase hydrophobicity of the wood surface require further investigation. In this study, a thermo-mechanical densification process was applied to Gmelina arborea (gamhar) wood. Three temperatures were used (140 °C, 160 °C and 180 °C) and two compaction rates (20 % and 40 %), applied for 30 minutes in a hot hydraulic press with final pressure of 2,5 MPa. Chemical changes, wettability and surface roughness of control and densified samples were investigated, as well as morphological changes. Densification partially degraded the hemicelluloses. Consequently, the wettability of the tangential surface of the densified wood decreased, with a more hydrophobic surface. Similarly, densification reduced surface roughness, especially when filtering was used for natural wood structures, with morphological changes on the surface of the densified samples. Densification with the highest temperature (180 °C) and 20 % compaction created the most hydrophobic surface (>90 °). In contrast, densification with the lowest temperature (140 °C) and compaction of 40 % provided the best results of the roughness parameters, with significant reductions, making it an applicable technique to minimize the roughness of wood in general and improve surface quality.


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Author Biographies

Douglas Edson Carvalho, Universidade Federal do Sul da Bahia. Centro de Formação em Ciências Agroflorestais. Ilhéus


Márcio Pereira da Rocha, Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba, Paraná, Brasil


Ricardo Jorge Klitzke, Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba, Paraná, Brasil


Pedro Henrique Gonzalez de Cademartori, Universidade Federal do Paraná. Departamento de Engenharia e Tecnologia Florestal. Curitiba



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How to Cite

Carvalho, D. E., Pereira da Rocha, M. ., Klitzke, R. . J. ., & Gonzalez de Cademartori, P. H. . (2024). Surface changes in wood submitted to thermomechanical densification . Maderas. Ciencia Y Tecnología, 26.




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