Low-Cost Calcined. Aluminas... Key to Uniform.High. Quality
IDEAL ADDED R e y n o l d s C a l c i n e d Aluminas are prepared from aluminum hydroxide, heated a t between 1100° C and 1300° C. Calcined Alumina, a high purity compound produced in a combination Bayer-Sinter process, has only minimum traces of oxides of iron, silicon and titanium. Careful quality control a n d large volume production assures a high degree of purity a n d uniformity. Chemical Specifications TYPICAL CHEMICAL PROPERTIES OF R-2003 CALCINED (Analysis in Percent on Dry Basis)
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ALUMINA
Grade
AbCb
Na20
S1O2
Fe203
* Total Water
R-2001
99.1
0.40
0.035
0.020
R-2003
99.1
0.40
0.035
0.020
0.5 0.3
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TYPICAL SIEVE ANALYSIS—R-2001 AND R-2003 (Cumulative Analyses in Percent) Particle Size Classification
on 200 Mesh
Thru 325 Mesh
Medium
40 to 80
OtolO
1
SPECIFICATIONS FOR SHIPMENT (Analyses in Percent on Dry Basis) Na-,0 (Max.)
SiO, (Max.)
R-2001
0.50
0.04
Fe 2 0 3 (Max.) 0.03
R-2003
0.50
0.04
0.03
Grade
Total H2O* (Max.)
2.5 0.5
•Total water refers to the total of that actually present plus that which could possibly be adsorbed i n an atmosphere 50% saturated with moisture.
Low, c o n t r o l l e d adisorbfion is one of t h e most important characteristics of R-2003 Calcined Alurnina. Because it will adsorb only trace quantities of water, shrinkage is less t h a n t h a t of aluminas produced a t lower temperatures. Distortion of the finished product is a t a m i n i m u m because there is less water t o escape, and because about 9 0 % of t h e alumina i n R-2003 is crystalline aipha alumina. Re-crystallization is minimized. R-2003 Calcined Alumina is also highly resistant t o shock —both t h e r m a l and mechanical, a n d will imp a r t this characteristic t o the finished products. R-2003 can be ground t o its ultimate particle size — less than 10 microns —with low dust losses. Thus, i t dissolves quickly, with less power consumption, in electric furnace operations.
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Best Applications of R - 2 O 0 3 Calcined Alumincss:
Abrasives — R-2003 is treated t o t h e hardest form of alumina, corundum, with a hardness of nine o n itie Mohs scale. T h e resulting abrasive is ideal for cool precision grinding of hard metal alloys. Refractories — Where resistance t o extremely high temperatures is important, R-2003 fills a vital function, both i n production equipment and final product. Replacing more expensive and scarce compounds, R-2003 adds refractoriness to tank and furnace linirLgs for glass production. Toughness is added t o the fimal product in almost direct proportion. Glass — T h e toughest, hardest glass, with high luster — such as cookware, table crystal, drug ampules — contains alumina, often R-2003. Alumina improves t h e luster of glass, makes i t more resistant to c h e m ical attack, mechanical and thermal shock. Polishing, Buffing— Calcined Aluminas a r e used extensively i n compounds t o polish stainless steels and hard alloys, as well a s softer metals. Laboratory Ware — Calcined a l u m i n a m a k e s crxicibles, kiln furniture, laboratory glassware and oth*er laboratory equipment resistant t o chemical attack, usable with high temperatures. I t is also used For insulator bodies, ceramic glazes, tile bodies and saggeirs. Grinding Balls — Dense, hard grinding balls are rna
