ZIRCAR Ceramics’ Bubble Alumina is a rigid, low-density, insulating refractory comprised of ZIRCAR Ceramics’ Alumina Bubble Types IB-100A and IB-100B bonded in high-purity Alumina Cement Type AL-CEM. While Bubble Alumina exhibits a bulk density twice that of a premium -grade alumina fiber insulator, Bubble Alumina’s structure consists primarily of closed air-filled thin-walled cells which combine to give it exceptional hot strength and low thermal conductivity. This makes Bubble Alumina an effective high-temperature thermal insulator in structural applications where insulating capabilities cannot be sacrificed, and appropriate for use at temperatures as high as 1825°C. It is pre-fired, contains no organics and exhibits high microwave and RF transparency. Its high alumina content makes it compatible with many extreme chemical environments. ZIRCAR Ceramics’ Bubble Alumina is manufactured on a custom basis and can be supplied in many complex shapes.