Research On Borosilicate Foam Glass Used As Inorganic Floating Carrier

Foam glass materials have a wide field of application. This study aims toinvestigate the kind of foam glass that is suitable for artificial floating island carrier.And a close research was made about the basic formular of foam glass, the choice offoaming agents, multiple additives and their effects on the structure and properties offoam glass. The phase composition was obtained by analyzing the XRD pattern ofsample. Diameter, distribution, shape of the foams was observed by SEM.Coefficient of thermal expansion and chemical stability were tested. Thecompressive strength was tested by universal testing machine.Experiment results indicated a proper ratio of sample SiO2/H3BO3to be4.615,the softening point of basic glass formula was about700℃, and the highestcompressive strength was3.68MPa, the sample density was0.394g/cm3, and theaverage coefficient of thermal expansion was about11.1010-6/℃（Roomtemperature~100℃）. The water corrosion resistance was quite good.Multiple kinds of additives with different content were added into basic foamglass formula and results showed that2.00%MnO2, or1.00%CaCO3could wellcontribute to the foaming progress. Since both of the two additives produced gasthrough decomposition, many pores in the samples were through holes.ZnO could add to the crystallization of foam glass. When ZnO content reached6%or8%, the compressive strength was ideal and the density was much larger thanthose of the basic formula, the spray deposition uniformity of pores would be worse;samples compressive strength with4%polycrystalline mullite fibers (PMFs) reached5.5MPa, with low density of0.5g/cm3as well.K3PO4could be used as foam stabilizer in this experiment. Research involved theeffect of K3PO4content on foams and the results showed that0.75%K3PO4was ableto well improve the viscosity of glass melt at high temperatures, which is beneficialfor the foam stability.The chemical stability of foam glass was benign and experiment studied thereplacement of partial Na2CO3with Li2CO3to improve the water corrosion resistanceto certain extent. With1.50%Li2CO3, the weight lose of samples decreased and theion concentration test showed that the ion concentration in acid solution was much higher than that of water solution for the reason of different H+activity.Experiment about foam glass with multiple additives was conducted and resultsshowed that the optimization didn’t occur in a way of addition style. The reason maylay in the complicated function mechanism, thus deep and through research wasrequired.