What Are The Ingredients And Properties Of High Alkali Fiberglass?
High-alkali glass fiber compositions drawn from flat glass are known as A-glass fibers, which have a NazO+K〇 content of 14.5% or more. This glass composition also falls near the PQ phase boundary in the NazO-CaO-Si0,ternary system. The replacement of some of the NazO with KO is intended to improve the chemical stability of the glass. The introduction of a small amount of AlzO; substitution of SiO, and substitution of MgO for CaO is to improve the crystallization properties of the glass.AHapioxnHa's study pointed out that the upper temperature of crystallization increases sharply when MgO>4%; the best crystallization performance is achieved when MgO is at 3%~4%. In addition, the optimum ratio of CaO/MgO should change in the direction of MgO decrease when AO:increases.
A glass fiber forming temperature is only about 1100 ℃, far lower than the E glass and C glass, so you can also use non-platinum leakage plate to produce some low-grade products. A glass fiber is not resistant to water erosion, but also not resistant to atmospheric moisture erosion, the product quickly become brittle, loss of strength and can not be practical applications. A glass fiber has been determined by atmospheric moisture erosion before and after the brittleness of the determination method is to use the knot circle method, that is, the fiber into a knot circle, to the ends of the pull, the knot circle diameter gradually decreases, write down the minimum knot circle diameter until the fracture before the D. With the diameter of the fiber d in addition to the diameter of the knot circle D, D / d ratio as a measure of the brittleness of a measure. Obviously, the larger the ratio, the greater the brittleness. a glass fiber before erosion, D = 174, D / d = 22.8, after erosion, D = 228, D / d = 29.8. have also used the same method to determine the E glass, C glass and A glass of the three kinds of glass fibers before and after the treatment of 100 water vapor brittleness, the results are shown in Figure 1-12. the figure can be seen from the glass fibers, A glass fiber after 16h after treatment , the D/d ratio increases significantly, while the changes of E glass and C glass fiber are not so much.
A glass fiber is not resistant to water, but it is resistant to acid erosion 5000cm? surface area of the fiber in 0.25mol/LHSO: in the boil clear 3h, the weight loss of 38.8mg. C glass fiber in the same conditions, the weight loss of 49.2mg, while the weight loss of the E glass fiber for 1063.9mg. Because of its resistance to acid, it can be applied to the production of acid-resistant products, such as battery separator plating tank, acid Storage tanks, sulfuric acid plant mist or acidic gas filter material.
Internationally, the United Kingdom attaches more importance to the production of A glass fiber. A glass fiber can be produced with flat broken glass, low cost. However, it is not water resistant and has low strength. Restriction of use or the use of hydrophobic treatment or coupling agent treatment, to protect the surface of the fiber from the erosion of water, the A glass fiber still has some application value. However, it is not suitable for production with clay crucibles.
