The specifications for decorative laminates and the corresponding test methods are issued by NEMA. They include thickness, wear, scratches, impact, dimensional changes, resistance to boiling water, staining, heat and light. In addition to the NEMA test method, each laminate has a series of more or less specialized side inspection methods to set the others. These include application-related inspection methods such as tool wear and stress cracking.
When processing veneers (decorative laminates), the cutting tools must be sharp, otherwise the trimeric limbs will have burrs. Operators have experienced very different productivity caused by slow tooling when processing different batches of laminates. At the time, the production schedule was not completed due to excessive downtime caused by tool changes. The initial investigation was to use the pigment used for finishing paper as a suspect. Although the measures were taken to improve the use of less abrasive pigments, this problem (although not serious) remains unresolved. Later, attention was transferred to the sand in the core paper. An additional troublemaker was discovered. The detection of the core paper composition and the silicon content is useful in identifying the troubles that paper can cause. However, the correlation between these inspection sides and field performance is not very good.
Obviously, the size and composition of the mineral particles present is important to determine the rate at which the tool wears. Better correlation can be obtained by subjecting the finished laminate to a standardized cutting procedure. The actual amount of wear of the cutting tool can be estimated under the microscope.
Stress cracking was observed around the veneer cut. This rupture is caused by stress, which is caused by a large change in the relative humidity around. A common method for detecting the tendency of laminate damage in this case is to use a 1.2 m X 1.2 m sample. The sample is first set at high humidity and then attached to a dry plywood substrate. Open a 0.3 m square cut in the center of the composite panel. The plate is then placed in a dry box and the cracking at the corners of the cut is periodically observed. The longer the interval before the crack occurs, the less the tendency for stress to break. In recent years, a series of less complex and more mature detection methods have been developed to make detection easier to implement.
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