Related Understanding of Refractory Aggregates - Henan Refractory Brick Manufacturer
Regarding the relevant understanding of refractory aggregates - Analysis of Henan refractory brick manufacturers: Refractory aggregates are divided into clay, high alumina, corundum, silicon, magnesium, magnesium aluminum spinel refractory aggregates, etc. according to their materials.
According to porosity, it can be divided into dense aggregate (also known as heavy aggregate) and lightweight aggregate (also known as porous aggregate). Dense aggregate refers to aggregates with a porosity not exceeding 30%. Dense aggregates can also be divided into ultra-dense aggregates (with a porosity of ≤ 3%), high-density aggregates (with a porosity of 3-10%), and ordinary dense aggregates (with a porosity of 10-30%). Lightweight aggregate refers to aggregates with a porosity greater than 45%. Lightweight aggregates can also be divided into ordinary lightweight aggregates (with a porosity of 45% to 80%), ultra lightweight aggregates (with a porosity of 80%), and special lightweight aggregates (such as alumina and zirconia hollow spheres).
In the production of amorphous refractory materials based on particle size, refractory aggregates are generally divided into coarse particle aggregates, medium particle aggregates, and fine particle aggregates. The particle size range of coarse, medium, and fine aggregates is related to the critical particle size (i.e. larger particle size) of the aggregates. When the larger particle size of bone particles is 8mm, the coarse aggregate particle size range is 8-3mm, the medium aggregate particle size range is 3-1mm, and the fine aggregate particle size range is 1-0.088mm (or 0.074mm). Less than 0.088mm (or 0.074mm) is not referred to as aggregate, but rather as powder (or matrix). If the aggregate has a larger particle size of 3.5mm, the coarse aggregate particle size range is 3.5-1.5mm, the medium aggregate particle size is 1.5-0.5mm, and the fine aggregate particle size is 0.5-0.074mm. The ideal aggregate particle grading should be able to achieve a relatively tight stacking, where the gaps left by the coarse particles after mutual contact and stacking are filled by the medium particles, and the small gaps left by the medium particles after filling are filled by the fine particles, forming a skeleton, while the remaining gaps are filled by powder. However, due to the irregular particle shape of refractory aggregates, it is difficult to achieve ideal aggregate particle grading in actual production. The grading of aggregates is usually determined by experiments, and the ratio of coarse, medium, and fine aggregates is (35-45): (30-40): (15-25).
The shape and shape of most refractory aggregate particles are multiphase polycrystalline materials, so the shape of refractory aggregate particles is not only related to the crystal structure, crystallization habits, and impurity content of each phase of the material itself, but also to the processing method of the material. If mullite is obtained by the electric melting method, as it is mostly self formed crystals that precipitate from the melt, according to the crystallization habit of mullite, it mostly appears as columnar polycrystalline aggregates. When broken, it breaks along the grain boundary direction with poor bonding force, and the broken particles also appear as columnar polycrystalline particles. The mullite obtained by sintering method is restricted by the surrounding environment due to its crystal development and formation, which has needle like, columnar, plate like, and granular forms, and is irregularly interspersed with each other. Therefore, the broken particles have irregular forms, such as sheet like, needle columnar, and angular forms. On the other hand, the morphology of the crushed refractory aggregate particles is also related to the material itself