Essential knowledge about wood panels: These are the terms you absolutely need to know!

Welcome to Zhoubao's Classroom! Zhoubao will be sharing interesting and practical knowledge about wood-based panels with you. Today is the third lesson in Zhoubao's Classroom, and we'll be discussing some professional terminology related to wood-based panels. Let's learn together!

Screw holding force

Screw-holding force refers to the frictional force between the board and the nail. When a nail is driven into the board, the fibers around the nail are compressed. Because the board is elastic, the compressed fibers exert pressure on the nail, creating a force that resists its removal. The magnitude of screw-holding force depends on the board's density, elasticity, moisture content, and grain direction. Strong screw-holding force is mainly reflected in the strong hold of the nail after it enters the board, making it less prone to loosening, allowing for repeated use of the nail hole, and giving the board the property of holding nails in place. Boards with good screw-holding force generally have higher hardness and density.

static bending strength and modulus of elasticity

Static bending strength and modulus of elasticity are the ratios of bending moment and section modulus of elasticity of a board material under maximum load, and are crucial properties that determine whether furniture will break during use. The static bending strength value we usually see for board products is the compressive strength that the board can withstand at fracture, expressed in MPa. The static bending strength and modulus of elasticity of a board are related to raw materials, processing technology, and other factors.

Internal bond strength

Internal bond strength refers to the ability of a board to resist failure when subjected to a tensile force perpendicular to its surface. Formerly known as "planar tensile strength," it is a crucial quality indicator for measuring the bonding strength between the raw materials within the board and a key indicator of the quality of the bonding between the fibers. Internal bond strength primarily depends on the board's density, adhesive application rate, and thickness. Increasing the core layer density enhances the board's internal bond strength. A directly proportional increase in adhesive application rate results in a larger area of ​​the board covered by adhesive, stronger fiber bonding, and a significant increase in internal bond strength. However, as the board thickness increases, its internal bond strength decreases.

Moisture content

Moisture content refers to the ratio of the mass of water contained in a material to its oven-dry mass. Excessive or insufficient moisture content can cause problems such as deformation and even cracking of the boards. Factors causing excessively high or low moisture content in boards mainly include the hot-pressing time, hot-pressing temperature, post-hot-pressing ventilation, and the moisture content of the raw materials. In addition, it is also related to the edge banding process after the boards are cut. It is recommended that when purchasing cabinets, you pay attention to whether the edge banding is flat, whether there is excess glue, and whether it is peeling off.

Bond strength

Bond strength refers to the firmness of the bond between the individual veneers, and is generally expressed as tensile shear strength. Inadequate bond strength can cause problems such as delamination, peeling, and other issues. There are many reasons for substandard bond strength, including excessive moisture content in the veneers, poor veneer quality, different veneer materials, insufficient glue application or uneven roller coating, poor flour quality during glue mixing, low hot-pressing temperature, short pressing time, insufficient pressure or improper pressure reduction process, blank spots in the glue application, veneer contamination, and foreign matter.

Impregnation and peeling

The immersion peel strength of engineered wood reflects the ability of the board to resist peeling deformation or the degree of peeling caused by the stress of the adhesive layer due to moisture expansion and shrinkage. It is also an indicator for evaluating the bonding performance of each adhesive layer in a product. When the board is used in the kitchen or bathroom, if it accidentally comes into contact with water, poor immersion peel strength may cause the board to delaminate and deform.

Ring ring, get out of class is over! That's all for today's lesson. Did everyone learn some of the technical terms related to wood-based panels? Hopefully, this will be helpful when you're buying wood-based panels.