Density board (MDF )material and density:
1. The fiber of wood is to show longitudinal arrangement along the trunk, the strength of vertical and horizontal direction, the performance such as expansion contraction has significant difference, less several times more than ten times.
2.The fiber arrangement of density board is arranged in longitudinal mode staggered direction. Although there is a little difference in strength in vertical and horizontal direction due to the forming way, the maximum difference is only about 10%, which is far less than wood.
3. Because the fiberboard’s anisotropic performance is equal, the material is dense and uniform, and the dimensional stability is very good, which is very convenient for construction and various mechanical processing. In use can not worry about material cracking, warping and deformation problems. The properties of fiberboard have a lot to do with density.
4. Fiberboard classification is generally based on density and there is a theoretical basis. Under the same conditions of raw materials and manufacturing process, the physical and mechanical properties of fiberboard, such as static flexural strength and tensile strength, have a linear relationship with density, and the higher the density, the better the physical and mechanical properties.
5. The water resistance of fiberboard is also the higher the density, the better its water resistance. After water absorption, the thickness expansion rate increases with the increase of density, but the linear expansion rate in the length direction has little relation with the change of density.
6. The thermal conductivity of fiberboard increases with density, and in particular, the thermal conductivity of fiberboard exceeding lg/cm3 is almost identical to that of wood. Soft fiberboard is a good insulation material because of its low density and poor thermal conductivity.