Effect of type and amount of periclase and dispersing additive type on the properties of vibrocast noncement periclase siliceous mix and samples from it
Researches have been carried out, as well as a composition and technological parameters for obtaining of vibrocast noncement periclase siliceous mix and products based on it have been developed. The possibility of using scrap of periclase products along with fused and sintered periclase, the use of which ensures obtaining of high strength properties of samples fired at 1450 C was established. The possibility of using domestically produced powdered quartz as a silicacontaining additive, and as dispersing additives: a polymer based on polyethylene glycol; a silicacontaining material with a particle size of less than 2 microns and an activity index of hydrogen ions of a 10 % aqueous suspension pH = 6; a chemical phosphate binder was shown. The optimum firing temperature of products (~ 1450 C), as well as the possible application temperature of fired products ( 1580 C), were established.
The vibrocast noncement periclasesiliceous mix and samples from it are characterized, depending on the type of magnesia aggregate and dispersing additive, by the following indicators of physicochemical properties: mass. %: MgO — not less than 86 %, SiO2 — within 6—8 %, Fe2O3 — not more than 1.5 %; grain composition, mm — 6—0; cold crushing strength of samples from this mix after heat treatment at a temperature of 350 and 1450 C is 20—45 and 30—80 N/mm2, respectively; residual dimensional changes during heating (shrinkage) at a temperature of 1580 C (2 h) — not more than 1 %; refractoriness — > 1780 C.
The developed vibrocast noncement periclasesiliceous mix is recommended for vibrocast monolithic linings of hightemperature units of ferrous and nonferrous metallurgy, cement and other industries, as well as for the manufacture of vibrocast largesized products and products of complex configuration, both unburnt and burnt.