The main component of silica bricks is silica, and polycrystalline transformation will occur during the production process, so the expansion coefficient of silica bricks is large.
The characteristics of silica bricks are high load softening temperature, but low thermal shock stability and lower refractoriness than general high-alumina bricks. Silica bricks have a volume expansion rate of 1.5~2.2% at a use temperature of 1450℃. Even when silica bricks are produced, the molds must be appropriately scaled according to the expansion coefficient. Leave space for expansion to make the size of silica bricks more accurate.
Rongsheng Silica Bricks for Sale
When silica bricks are produced, the transformation between quartz, tridymite, and cristobalite in the raw materials will destroy the original crystal structure and rearrange the structure. Because the activation performance is large during the firing process, the transformation temperature is high but slow, which produces a large volume expansion effect.
The silicon bricks have little solution formed at the firing temperature and are difficult to fire. A series of physical and chemical changes that occur during the firing process of silicon bricks will cause the size of silicon bricks to increase.
The temperature of silicon bricks changes greatly during the firing process: residual water is discharged from the bricks at 150°C, decomposition begins at 450°C, and dehydration is completed at 450~500°C. There will be a 0.82% volume expansion in the range of 550~650°C, and the solid phase reaction begins between 600~700°C, and the strength of the bricks increases. At 1100°C, the transformation rate of quartz increases, but the specific gravity of the bricks begins to decrease. At this time, the volume of the bricks increases due to the transformation of quartz into a low-specific gravity variant. Cracks will occur in silicon bricks in the range of 1100~1200°C.
The volume of silicon bricks changes during the heating process, at different temperature steps. The changes of silica are divided into 600°C, 600~1100°C, 1100~1250°C and above 1250°C. At 500~600℃, expansion occurs. At 700~800℃, there is micro-contraction. At 1000~1100℃, the contraction is greater. At 1200℃, the quartz transformation accelerates and the body begins to expand violently. The expansion range is different according to the expansion coefficient of different raw material types.
The biggest disadvantage of silica bricks is low thermal shock stability and low refractoriness, but high refractoriness under load. It is suitable for use in kiln linings in acidic atmospheres. To purchase high-quality silica bricks and zero-expansion silica bricks, please contact Rongsheng for free samples and quotes.
High alumina cement, also known as aluminate cement, has the advantages of high early strength, high-temperature resistance, and strong resistance to sulfate corrosion. In recent years, due to the rapid growth of the early strength of high alumina cement, early de-moulding, and tight construction schedules, the number of projects using high alumina cement to prepare concrete has continued to increase. However, the later strength of high alumina cement is unstable, and there is great controversy about its application in engineering. Studies have shown that the use of ultrafine powder as a mixture of high alumina cement can improve the later strength of high alumina cement.
Effect of Barite Powder on the Strength of High Alumina Cement
Baryte powder, commonly known as barite, is a naturally formed white inorganic salt and a neutral filler. Its relative density is 4.16, and it has the characteristics of light resistance and corrosion resistance, low oil absorption value, opaque to ultraviolet rays and X-rays, and radiation protection. Using natural mineral barite as an additive for aluminate cement can reduce the water requirement of the standard consistency of aluminate cement, improve the strength of cement, reduce the later strength regression, and not reduce the refractoriness of cement.
Adding an appropriate amount of barite powder admixture to high alumina cement can not only improve the early strength of high alumina cement but also inhibit the later strength shrinkage of high alumina cement. The appropriate amount of barite powder can promote the hydration of high alumina cement. The main reason why barite powder inhibits the later strength shrinkage of high alumina cement is that it inhibits the crystal transformation of CAH10 and C2AH8 to C3AH6 in the hydration products of high alumina cement. It should be noted that excessive addition of barite powder may cause the strength of high alumina cement to decrease. Therefore, in practical applications, it is necessary to make adjustments according to specific circumstances.
In general, the effect of barite powder on the strength of high-aluminum cement is a complex issue that requires comprehensive consideration of multiple factors. Future research can further explore the optimal addition amount of barite powder and the differences between different types of high-aluminum cement to better play the application value of barite powder in high-aluminum cement.
What is High-Temperature Resistant Cement? Aluminate, High Aluminum, Refractory
Rongsheng refractory cement sales. Rongsheng high-temperature cement, has many aliases, aluminate cement, high aluminum cement, high strength refractory high temperature resistant cement. It is a special cement that maintains good performance in high-temperature environment. It has high compressive strength, heat resistance, chemical corrosion resistance and low thermal expansion coefficient. It is suitable for engineering projects in harsh environments such as slag, high-temperature gas and chemically corrosive substances. Contact Rongsheng for a free quote.
Rongsheng Calcium Aluminate Cement – High Alumina Cement
High-temperature resistant cement is mainly used in high-temperature industrial fields such as metallurgy, petrochemical, and electric power. As well as the construction and maintenance of high temperature facilities such as furnaces, chimneys, smelting furnaces, and chemical equipment. Rongsheng high-temperature resistant cement, aluminate cement, refractory cement, high aluminum cement.
The main characteristics of high-temperature resistant cement are as follows:
High-temperature resistance. The sintering temperature of high-temperature resistant cement is as high as 1300-1600 degrees Celsius. It can maintain stable performance in a long-term high-temperature environment and is suitable for various high-temperature facilities and equipment.
High compressive strength. High-temperature cement has high compressive strength, can withstand large mechanical loads, and is suitable for high-strength and high-pressure engineering applications.
Good chemical corrosion resistance. High-temperature resistant cement has good corrosion resistance to a variety of acid, alkali, salt and other chemical media, and can maintain a long service life in harsh chemical environments.
Low thermal expansion coefficient. High-temperature-resistant cement has a low thermal expansion coefficient, can adapt to thermal expansion and contraction in high-temperature environments, and reduces the generation of cracks.
Excellent fire resistance. High temperature-resistant cement has good fire resistance, can effectively prevent the spread of fire, and improves the fire safety performance of buildings.
Detailed Explanation of Ingredients and Process of High-Strength Sulphoaluminate Cement
Take the production of 100 kg of high-strength sulphoaluminate cement as an example. Among them, sulphoaluminate cement clinker: 76 kg; silica fume: 9 kg; dihydrate gypsum: 10 kg; lithium carbonate 1 kg, calcium hydroxide 2 kg and aluminum sulfate 1.5 kg; retarder: 0.5 kg. Weigh the raw materials of each component according to the above mass percentage. After mixing evenly, grind them together to a fineness of 360m2/kg specific surface area to make a finished cement product.
Sulphoaluminate cement. The high-strength sulphoaluminate cement produced by this method has a simple production process, is easy to implement and has low cost. It can effectively adjust the setting time of sulphoaluminate cement to meet the construction requirements of actual projects.
Rongsheng High Alumina Cement Manufacturer
Rongsheng Refractory Material Manufacturer is a powerful manufacturer and seller of refractory materials. Rongsheng’s high alumina cement (CA50/CA60/CA70/CA80, etc.). High temperature resistance and excellent performance. Rongsheng’s refractory products have been sold to more than 120 countries around the world, such as South Africa, Chile, Egypt, Colombia, Uzbekistan, Italy, Indonesia, Ukraine, Hungary, Spain, Kenya, Syria, Zambia, Oman, Venezuela, India, Peru, the United States, Ethiopia, etc. Contact Rongsheng for more information on refractory lining materials.
