Applications of ground fiberglass
Ground glass fiber is made by grinding glass fiber raw strands using crushing equipment such as a hammer mill or ball mill. The average length of the fiber is 30 to 100 microns. When observed under a microscope, its cross-sectional area is cylindrical. Ground glass fiber in my country is usually calibrated by fiber length and fiber diameter. For example, EMF-200 refers to ground fibers with an average diameter of 7.5 microns and an average length of 80 to 110 microns.
At present, ground glass fiber is mainly used as high-performance friction material in my country. The traditional filler of friction materials is asbestos. However, it has been reported abroad that asbestos is a carcinogen. The international market has boycotted friction materials containing asbestos in recent years, providing a broad market for grinding glass fibers.
The ground glass fiber used as friction material undergoes surface chemical treatment to accelerate the penetration of resin and meet special molding performance and product performance requirements. Its specifications include EMF-200, EMF-250 and EMF-300, and the corresponding fiber length fluctuation ranges are 110-80 microns, 80-50 microns and 50-30 microns.
The friction material added with ground glass fiber not only has a high friction coefficient, but also has durability and thermal stability. When it comes into frictional contact with the close parts (such as the rotor), it only produces slight noise and causes wear of the rubbed parts. Volume is reduced to a minimum.
This high-performance friction material can be widely used as brake pads and clutch plates for automobiles, brake shoes for passenger and freight vehicles, railway locomotives and various drilling rigs, friction blocks for stamping equipment and engineering and mining machinery, and cones for lifting machinery. Shaped brake rings, etc.
Ground glass fiber can also be used as functional filler in ABS plastic to modify ABS plastic to meet the requirements of plastic processing and product application performance. When a factory was producing parts such as the program controller bottom plate and cover plate of a fully automatic washing machine, because they were made of pure ABS plastic, the bottom plate and cover plate were seriously warped and deformed, the dimensions of the parts were unstable, and the screw holes slipped. teeth, causing many finished products to be scrapped because they could not be assembled. Later, ground glass fiber was used to fill ABS plastic to modify the plastic: the shrinkage rate was reduced from the original 1% to 2% to 0.4% to 0.5%. When tightening self-tapping screws, the teeth will not slip or crack, and it will be manufactured at the same time. The board surface and parts are smooth, stiff and not warped, and the plastic processing performance is good. In addition, adding ground glass fiber to the laminate can improve the crack resistance and wear resistance of the laminate, reduce the shrinkage of the laminate, and improve the lamellar strength. At the same time, it also plays a certain role in improving the bending elastic modulus of laminates and compressing elastic molds. When the resin mixture with ground glass fiber is added to the mold, it can smooth the outer surface defects, round the edges and corners of the mold structure, and also round the reinforcing ribs covered with glass cloth that are pre-connected to the outside of the mold structure.
After the resin reinforced with ground glass fiber is cured, the hardness of the product is higher, and its thermal expansion performance is similar to that of hand lay-up FRP reinforced with glass cloth, so the product is less likely to crack.
The simultaneous use of surface-active components and ground glass fibers in the resin system can improve its wet strength performance, reduce water absorption, and increase the retention rate of wet strength.