China’s stone composite panels have been used for nearly 30 years and have been widely used in architectural decoration projects. They have decorated a large number of buildings and saved a lot of stone resources. However, this is a special product that is completely different from stone products. Its processing technology is also completely different from that of traditional stone products. It has a specific processing technology, abides by its specific processing technology regulations, and implements its own quality standards.
If the processing is not strictly processed according to its standards, the quality of the processed products will not meet the requirements, which will lead to serious problems. Among them, hollowing is the most fatal problem of stone composite panels. Once it occurs, it may be returned by customers, and the company will suffer huge losses and face huge compensation. Even the processing company will be hit hard and go bankrupt. This is not alarmist. Some stone processing companies have indeed experienced such difficulties and setbacks.
The composition of composite panels
Simply put, stone composite panels are products composed of stone and another material bonded by adhesives.
Figure 1 is a stone-aluminum honeycomb composite panel. It can be seen from Figure 1 that the stone aluminum honeycomb composite panel is composed of a stone surface material and a base aluminum honeycomb. The two are bonded together with an adhesive.
Aluminum honeycomb composite panels are classified according to the type of base material:
(1) Stone-ceramic tile composite panel; (2) Stone-stone composite panel; (3) Stone-silicate composite panel; (4) Stone-aluminum-plastic composite panel; (5) Stone-aluminum honeycomb composite panel; (6) Stone-glass composite panel; (7) Stone-wood composite panel; (8) Stone-plastic composite panel; (9) Stone-metal composite panel(10) Stone-insulation material composite panel
Since the stone composite panel is made by bonding stone with other materials using an adhesive, if the bonding process is not strictly in accordance with the process flow and technical standards, the processed stone composite is very likely to have hollows. Figure 6 shows the surface of the aluminum honeycomb being roughly ground by hand to make the surface rough and more firmly bonded with the composite glue; Figure 7 shows the composite glue being scraped on the stone surface.
Fatal quality problems caused by hollowing of stone composite panels:
(1) The surface stone of the composite panel is separated from the substrate. If the stone composite panel is hollowed because there is a gap between the stone and the substrate, it will greatly affect the bonding force and strength between the stone and the substrate, resulting in the pull-out force not meeting the standard and the stone and the substrate being easily separated.
(2) Cracks in the surface material of the composite panel
If the stone composite panel is hollowed because there is a gap between the stone and the substrate, the adhesive will generate a lot of heat during the curing process, which will increase the tensile force on the stone, easily tear the stone thin plate, and crack the surface material of the composite panel. The cracking of the stone affects the appearance of the stone surface and can also cause the cracks on the stone surface to further expand the area of the stone surface cracks over time.
(3) Greatly reduce the strength of the stone surface. Hollowing occurs in the stone composite board, and the strength of the stone at the hollowing point is greatly reduced. Since the thickness of the stone in the stone composite board is mostly about 5 mm, some are even lower. Such thin stones have greatly reduced strength, and the hollowing will cause the stone to crack or break when slightly impacted by external force.
(4) Greatly reduce the thaw and freeze strength of the stone. Hollowing occurs in the exterior wall composite board, and the thaw and freeze strength of the stone will be greatly reduced. Under severe conditions of ice, snow or sunlight, the stone will be greatly damaged and broken.
(5) The waterproof performance of the stone is greatly reduced, thus affecting its mechanical properties. If hollowing occurs in the stone composite board of the exterior wall, rainwater will penetrate into the stone from the hollowing, greatly reducing the waterproof performance of the stone, thus affecting the mechanical properties, corroding the substrate, destroying the safety, and increasing the risk of the exterior wall.
(6) The composite board floor has a greatly increased breakage rate due to hollowing. Once the floor has hollowed out, it can be said that this composite board can only be scrapped and become a garbage product. After the floor is hollowed, it will break when it is impacted by a little external force. When high heels step on the hollow stone composite board, it will immediately crack. A well-known large-scale stone processing company in China once supplied hollow composite panels worth millions of yuan to foreign countries, which were returned by a large number of customers who claimed compensation. The company has since stopped production.
In the past two years, stone background walls have emerged in large numbers. Home decoration pursues a more luxurious and atmospheric style. The specifications of background wall products are getting bigger and bigger. In order to reduce the price of background wall products, many stone processing companies make background products into composite boards. Stone composite boards are currently showing an upward trend.
To ensure the quality and safety of stone composite panels, stone processing companies must strictly follow the process flow of stone composite panels, strictly control the hollowing problem of stone composite panels, and ensure that the processed stone composite panels have no hollowing. Otherwise, once the processed stone composite panels have hollowed out, especially in batches, the stone composite panel processing companies may suffer a “catastrophe”!
