4results about How to "Improve high temperature flexural strength" patented technology

The invention relates to the technical field of precision casting of turbine blades, in particular to a ceramic core for a nickel-based superalloy isometric crystal hollow turbine blade and a preparation method of the ceramic core. The ceramic core is prepared by mixing refractory powder and a paraffin-based plasticizer and then sintering the mixture at a high temperature, and the mass ratio of the refractory powder to the paraffin-based plasticizer is (75-85): (15-25); the refractory powder is composed of quartz glass powder, alumina powder and natural crystalline flake graphite, and the mass ratio of the quartz glass powder to the alumina powder to the natural crystalline flake graphite is (72-77): (20-25): (0.5-3); the paraffin-based plasticizer is prepared from refined paraffin, beewax and low-density polyethylene, and the mass ratio of the refined paraffin to the beewax to the low-density polyethylene is (40-50): (40-50): (5-10). The natural flake graphite is creatively added into the raw materials of the ceramic core, so that the flowability of slurry is improved, the high-temperature bending strength of the ceramic core is improved, and the depoling performance of the mold core is improved.

A refractory material and its preparation method and application, belonging to the technical field of refractory materials, the refractory material uses plate-shaped corundum modified coarse aggregate, plate-shaped corundum fine aggregate, modified artificial graphite, antioxidant, anti-corrosion agent and adhesive as raw materials. Among them, the plate-shaped corundum coarse aggregate is modified by combining coal gangue purification powder and nano-grade carbon black, which has a smaller porosity, increased volume density and strength. The delayed petroleum coke powder is modified by using plate-shaped corundum powder and phenolic resin powder, and the modified artificial graphite is sintered to prepare the modified artificial graphite, which has a certain improvement in compressive strength, thermal shock resistance, creep rate, etc., and the graphite component is not exposed on the surface of the slide. The modified plate-shaped corundum coarse aggregate and the modified artificial graphite are used in combination, which can greatly improve the strength, good thermal shock stability, and low creep rate; each time the hole is expanded, the diameter is small, the erosion resistance and erosion resistance are good, the carbon content entering the molten steel is very low, and it will not greatly affect the carbon content of low-carbon molten steel, and can be used for the pouring of low-carbon molten steel.

The invention relates to the technical field of refractory materials, in particular to a low-chromium corundum brick and a preparation method and application thereof. The low-chromium corundum brick is prepared from raw materials comprising a component a and an additional binding agent, the component a comprises the following components in percentage by weight: 25 to 35 percent of low-chromium chromium corundum; 50 wt%-70 wt% of an aluminum-magnesium-carbon regenerated material; 10 wt% to 20 wt% of a premix; the sum of the dosages of all the components is 100%. In the low-chromium chromium corundum, the mass content of chromium oxide is less than 5%; meanwhile, the particle size ratio of the low-chromium chromium corundum and the aluminum-magnesium-carbon regenerated material is limited, and the components and content of the premix are limited; the additional binding agent is phenolic resin; and the external binding agent accounts for 2-3% of the mass of the component a. The low-chromium corundum brick provided by the invention can replace tabular corundum to serve as a molten steel tank bottom brick, and is equivalent and even better in use performance and lower in operation cost.

This invention relates to the field of green special refractory ceramics technology, and particularly to a green refractory thermal shock resistant converter slag-blocking sliding plate and its preparation method. The raw materials for the aforementioned green refractory thermal shock resistant converter slag-blocking sliding plate, by weight, include: 50-80 parts of tabular corundum particles, 10-20 parts of fine tabular corundum powder, 1-3 parts of α-alumina micro powder, 5-10 parts of zirconium mullite, 5-10 parts of dispersed graphite, 1-2 parts of carbon fiber, 1-2 parts of silica micro powder, 1-2 parts of titanium powder, 1-5 parts of boron nitride, 1-5 parts of boron carbide, and 1-3 parts of phenolic resin; the raw materials for the dispersed graphite include: flake graphite powder, ferric nitrate, urea, potassium nitrate, and surfactant; the mass ratio of flake graphite powder, ferric nitrate, urea, potassium nitrate, and surfactant is 5-10:1-3:1-3:1-2:1-2. The thermal shock resistance, compressive strength, and high-temperature flexural strength of the converter slag-blocking sliding plate obtained by this invention are simultaneously improved.