# Medium Density Fiberboard (MDF)

MDF is a wood-based material. It has the highest density among wood-based materials. In addition, it has the lowest ductility and the highest thermal conductivity. The graph bars on the material properties cards below compare MDF to other wood-based materials (top) and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

## Mechanical Properties

Compressive (Crushing) Strength

10 *MPa* 1.5 *x 10 ^{3} psi*

Elastic (Young's, Tensile) Modulus

4.0 *GPa* 0.58 *x 10 ^{6} psi*

Elongation at Break

0.5 *%*

Poisson's Ratio

0.25

Shear Modulus

2.5 *GPa* 0.36 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

18 *MPa* 2.6 *x 10 ^{3} psi*

## Thermal Properties

Specific Heat Capacity

1700 *J/kg-K* 0.41 *BTU/lb-°F*

Thermal Conductivity

0.3 *W/m-K* 0.17 *BTU/h-ft-°F*

Thermal Expansion

12 *µm/m-K*

## Other Material Properties

Density

0.75 *g/cm ^{3}* 47

*lb/ft*

^{3}Dielectric Strength (Breakdown Potential)

0.5 *kV/mm* 0.020 *V/mil*

## Common Calculations

Stiffness to Weight: Axial

3.0 *points*

Stiffness to Weight: Bending

71 *points*

Strength to Weight: Axial

6.7 *points*

Strength to Weight: Bending

20 *points*

Thermal Diffusivity

0.24 *mm ^{2}/s*

Thermal Shock Resistance

27 *points*

## Followup Questions

## Further Reading

Wood Handbook: Wood as an Engineering Material, Forest Products Laboratory, USDA Forest Service, 1999

CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015