The Performance Optimization Of Insulation Materials Made By Glass Hollowspheres

The insulation boards made by porous glass have the superiority on Nonflammable, low water absorption rates compared with the most popular insulation boards made by organic materials, but the traditional way to build the insulation boards made by porous glass have the disadvantage of high sintering temperature, uncontrolled size of pore and so on. In this passage, we use the way of sintering the stacked glass hollowsphere green bodies to make the insulation boards made by porous glass, and study on the changing of the glass hollowshpere green bodies during sintering, the influence of sintering systems, and try to find out the best system that could sinter the glass hollowshpere green bodies to get the most wonderful performance, and try to use DTA, SEM, XRD and conductivity meter and so on to perform the insulation boards made by glass hollowspheres.Glass hollowspheres start to connect other hollowspheres with connection necks when reaching the softening temperature, with the raise of the sintering temperature, connection neck gradually increases, until the boundaries between glass hollowspheres are not so clear.When the sintering temperature is at 660 ℃, boundaries between glass hollowspheres could not be seen clearly, and become a whole insulation boards with many much hollows in it. And then, as the temperature raises, the hollows are combined and becoming binger. And the appearance density goes down.Sintering between 660℃ and 780℃, with the raising of temperature, the appearance density will go down; as the temperature goes up, the viscosity of glass will go down, and could not hold the air in the body, the appearance density will go up. At 700℃, the glass will crystallized. As the temperature goes up, more crystal will come out. And the materials will be segregation and raise the rate of open hole. superiority;At 700℃, extended of insulation time will make gas phase materials in melting state glass grown up, reduced the samples of capacity heavy, not as in 780℃; but long time in high temperature state will caused glass into nuclear volume increased, led to samples in the analysis crystal of intensified; lower of capacity heavy means the insulation boards made by glass hollowsphere within stomatal more, or stomatal larger, can significantly reduced glass hollow micro beads of thermal conductivity coefficient; and the raising rate of opened hole will make the internal of gas circulation intensified, caused thermal conductivity coefficient raising.Improve sintering speed of warming rate can increased insulation boards made by glass hollowsphere material within gas phase material and melting state glass of temperature increases, gas phase material of thermal expansion and contraction of range also more big,can reduced glass hollow micro beads insulation material of capacity heavy, but reducedrange limited; while due to does not gives glass full of into nuclear time, and relative reduced has glass reached into nuclear temperature of time, on analysis Crystal volume of effects smaller.Determined by experiment, at sintering temperature of 780 ℃, heating rate 3℃/min holding time samples of 0.5h has the best overall performance, its density is 0.131g/cm3, 6.955%volume rate of water absorption, compressive strength of 1.275 MPa and measured the samples at 25℃(measured 23.06 ℃) thermal conductivity of 0.602W/(m · k).