In order to improve the anti-explosion performance ofρ-Al_(2)O_(3) bonded corundum castables,H_(2)O_(2) was added(0,0.025%,0.050%,0.075%,0.100%and 0.125%,by mass)as the anti-explosion agent.After mixing and casting,s...In order to improve the anti-explosion performance ofρ-Al_(2)O_(3) bonded corundum castables,H_(2)O_(2) was added(0,0.025%,0.050%,0.075%,0.100%and 0.125%,by mass)as the anti-explosion agent.After mixing and casting,specimens were prepared.Some specimens were cured at room temperature for 12 h and demoulded for the anti-explosion performance test at different temperatures(450,500,550,600,650,700,750 and 800℃);the other specimens were cured,dried and fired,and tested in terms of the apparent porosity,the density,the cold mechanical properties,the air permeability and the pore size distribution.The results show that:(1)with the increase of the H_(2)O_(2) addition,the anti-explosion performance of castables increases gradually,the average pore size increases gradually,and the density and the strength decrease gradually;(2)by comprehensive consideration,the appropriate addition of H_(2)O_(2) shall be within 0.075%.展开更多
Inner vapor pressure and temperature of vulnerable explosive spalling positions in refractory castables during rapid drying were measured by embedding pressure transmitting pipes and thermocouples during casting. The ...Inner vapor pressure and temperature of vulnerable explosive spalling positions in refractory castables during rapid drying were measured by embedding pressure transmitting pipes and thermocouples during casting. The measured vapor pressure, temperature, and tensile strength of the castables were analyzed and discussed. A hollow sphere shell model was used to analyze the stress induced by the vapor pressure based on the structure of refractory castables. The mechanism of refractory castables explosive spalling caused by vapor-induced pore split was proposed. By comparing the vapor-induced stress and the tensile strength of the castables, the explosive spalling mechanism was validated quantitatively.展开更多
Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of alumi...Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of aluminum smelting furnaces and smelting processes,and the service conditions of refractories and the requirements for refractory lining were also described and discussed.展开更多
In this paper,an ideal structural model and a scientific and practical mathematical model of high temperature permeability testing technology were established based on the formula of gas permeability at room temperatu...In this paper,an ideal structural model and a scientific and practical mathematical model of high temperature permeability testing technology were established based on the formula of gas permeability at room temperature according to Darcy’s equation and Forchheimer equation and combined with the basic law of gas mechanics and the resistance loss of gas movement process at high temperatures.Through a gas heater,the safe heating of gas from room temperature to the test temperature was realized;the pressure sealing of high temperature permeability test technology was studied using high temperature resistant flexible material instead of silica gel material and combining preloading with system expansion and continuous loading.Based on the above research,a high temperature gas permeability tester for refractories has been developed and the test temperature can be up to 1000℃.The equipment was applied to research refractories,showing well using effects.展开更多
文摘In order to improve the anti-explosion performance ofρ-Al_(2)O_(3) bonded corundum castables,H_(2)O_(2) was added(0,0.025%,0.050%,0.075%,0.100%and 0.125%,by mass)as the anti-explosion agent.After mixing and casting,specimens were prepared.Some specimens were cured at room temperature for 12 h and demoulded for the anti-explosion performance test at different temperatures(450,500,550,600,650,700,750 and 800℃);the other specimens were cured,dried and fired,and tested in terms of the apparent porosity,the density,the cold mechanical properties,the air permeability and the pore size distribution.The results show that:(1)with the increase of the H_(2)O_(2) addition,the anti-explosion performance of castables increases gradually,the average pore size increases gradually,and the density and the strength decrease gradually;(2)by comprehensive consideration,the appropriate addition of H_(2)O_(2) shall be within 0.075%.
文摘Inner vapor pressure and temperature of vulnerable explosive spalling positions in refractory castables during rapid drying were measured by embedding pressure transmitting pipes and thermocouples during casting. The measured vapor pressure, temperature, and tensile strength of the castables were analyzed and discussed. A hollow sphere shell model was used to analyze the stress induced by the vapor pressure based on the structure of refractory castables. The mechanism of refractory castables explosive spalling caused by vapor-induced pore split was proposed. By comparing the vapor-induced stress and the tensile strength of the castables, the explosive spalling mechanism was validated quantitatively.
文摘Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of aluminum smelting furnaces and smelting processes,and the service conditions of refractories and the requirements for refractory lining were also described and discussed.
基金National Natural Science Foundation of China(General Program 51172215).
文摘In this paper,an ideal structural model and a scientific and practical mathematical model of high temperature permeability testing technology were established based on the formula of gas permeability at room temperature according to Darcy’s equation and Forchheimer equation and combined with the basic law of gas mechanics and the resistance loss of gas movement process at high temperatures.Through a gas heater,the safe heating of gas from room temperature to the test temperature was realized;the pressure sealing of high temperature permeability test technology was studied using high temperature resistant flexible material instead of silica gel material and combining preloading with system expansion and continuous loading.Based on the above research,a high temperature gas permeability tester for refractories has been developed and the test temperature can be up to 1000℃.The equipment was applied to research refractories,showing well using effects.
