Abstract
Balsa wood is one of the preferred core materials in structural sandwich panels, in applications ranging from wind turbine blades to boats and aircraft. Here, we investigate the mechanical behavior of balsa as a function of density, which varies from roughly 60 to 380 kg/m3. In axial compression, bending, and torsion, the elastic modulus and strength increase linearly with density while in radial compression, the modulus and strength vary nonlinearly. Models relating the mechanical properties to the cellular structure and to the density, based on deformation and failure mechanisms, are described. Finally, wood cell-wall properties are determined by extrapolating the mechanical data for balsa, and are compared with the reduced modulus and hardness of the cell wall measured by nanoindentation.
Original language | English |
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Pages (from-to) | 75-90 |
Journal | Mechanics of Materials |
Volume | 84 |
DOIs | |
Publication status | Published - May 2015 |
MoE publication type | A1 Journal article-refereed |
Funding
Funding provided by BASF through the North American Center for Research on Advanced Materials (Program Manager Dr. Marc Schroeder; Dr. Holger Ruckdaeschel and Dr. Rene Arbter) is gratefully acknowledged. The Hobby Shop in MIT is thanked for their help in preparing the balsa wood specimens for mechanical testing. Mike Tarkanian (MIT) is thanked for his help in planning the torsion tests. Dr. Alan Schwartzman (MIT) is thanked for his kind support with the nanoindentation experiments. Patrick Dixon (MIT) is thanked for his help in conducting the mechanical tests and discussing the results.
Keywords
- Balsa
- Failure
- Mechanical properties
- Nanoindentation
- SEM