The alumina bubble produced by our company is a hollow spherulitic heat-insulating meterial, which is made by electrofused method. It is noted for its light-weight, heat-resistance, close pore. It is an ideal filler for high-temperatuerfurnaces and excellent aggregate of light weight castable refractory.it is also and ideal heat-insulating and energy-saving refractory.

Index Properties		Alumina Bubble
		Guarantee value	Typical Value
Chemical composition	Al2O3	≥98.5	99.2
	SiO2	≤0.2	0.18
	Fe2O3	≤0.15	0.10
	NaO	≤0.4	0.3
Packing density（g/cm3）		0.5-1.0	0.85
Damaged rate (%)		≤15	12
Refractoriness (℃)		1790
Grain Size: （mm）		0.25-5，0.2-1，1-3，3-5，