RESEARCH IN THE FIELD OF PREPARING MOLDED AND UNMOLDED REFRACTORIES BASED ON HIGH-ALUMINA HCBS. PART 7. SINTERING AND SECONDARY MULLITE FORMATION OF MATERIALS BASED ON COMPOSITE COMPOSITION HCBS DURING NONISOTHERMAL HEATING AND ISOTHERMAL FIRING

摘要

The effect of nonisothermal heating in a high-temperature dilatometer and isothermal heating in the range 900-1600 degrees C on sintering and secondary mullite formation for specimens based on composite composition HCBS, including with refractory clay additions, is studied. Maximum shrinkage values of 0.4-1.3% depending on composition are noted with nonisothermal heating up to 1200-1250 degrees C or after isothermal firing at 1100-1200 degrees C. Specimen growth index (up to 2.0-2.5%) after high-temperature firing depends on SiO2 content that indicates the volume of secondary mullite formed.