index	High alumina brick
item	RL-65	RL-55	RL-48
AL2O3 %≥	65	55	48
Refractoriness ℃≥	1780	1760	1740
0.2MPArefractoriness under load，，℃≥	1500	1470	1420
Permanent linear change after heating，，%1500℃*2h 1450℃*2h 1350℃*2h	0.1-0.4		-
	-		0.1-0.4
	-
Apparent porosity %≤	24	24	24
Cold Crushing Strength，MPA≥	49	44.1	39.2