Artificial boxwood board expansion and contraction
Since the veneers are perpendicular to each other in the texture of the adjacent layers, when the moisture is absorbed or dried, the adjacent layers are mutually restrained, so that the dimensional shape stability is good. The hard fiberboard is treated at high temperature, and the fiber dimensional stability is improved compared with the general wood fiber. The equilibrium moisture content is lower than that of the wood at the same temperature, but due to the asymmetry of the two surfaces, the surface area of the mesh has a large surface area and expands. It is inconsistent with the contraction and is prone to deformation. The soft fiberboard has a small specific gravity, a large number of voids, and a fast moisture absorption. The equilibrium moisture content is larger than that of the hard fiberboard, and the deformation caused by expansion and contraction is small, but the water and moisture resistance is poor. The dimensional stability of the particleboard is related to the use of rubber, the amount of glue, the amount of water repellent, the hot pressing condition, the bulk density, etc. Under the same process conditions, its dimensional stability is inferior to that of plywood and fiberboard. The dimensional stability of the artificial boxwood not only affects its direct usability, but also affects the process and product quality of the surface decoration. When the moisture content of the artificial boxwood board changes, as the sheet shrinks and expands, the decorated sheet is repeatedly subjected to tensile stress or compressive stress, and corresponding stress is generated between the interface of the facing material and the artificial boxwood board, resulting in the facing material. Peeling, wrinkling or cracking. Therefore, in the artificial yellow box wood decoration, in addition to trying to improve the stability of the artificial boxwood substrate, the decorative material is also required to have a certain elasticity and toughness to compensate for the swelling and shrinkage of the artificial boxwood substrate.
Uneven thickness of artificial boxwood
The artificial boxwood boards are all made under hot pressing conditions, and the inconsistency in compression occurs due to uneven thickness of the substrate on the flat layer or uneven spreading. Thus, even if the surface of the substrate is sanded, the thickness is adjusted, but when it is swollen or dried, the unevenness of the surface may cause unevenness of the surface. Therefore, the thickness of the single veneer of the plywood should be as uniform as possible, and the particleboard and fiberboard paving should be as uniform as possible to minimize the thickness tolerance of the slab.
