Novel composition

Abstract

A composition with a Mohs hardness of at least 6.0, wherein said composition contains at least 30 weight percent of spinel crystals, at least 10 weight percent of glass, and less than 10 weight percent of ferrometalsilicate. The composition also contains particles with a particle size distribution such that at least about 95 weight percent of such particles are smaller than about 2.0 millimeters; at least about 70 weight percent of such particles have a particle shape that is either the blocky particle shape or the pyramidal particle shape. At least 20 weight percent of the spinel crystals are equiaxed spinel crystals; the weight/weight ratio of said spinel crystals to said glass is at least 1.2/1; the composition has a melting point in excess of 1440 degrees Celsius; and the composition has a density of from about 3.0 to about 4.5.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described by reference to the specification, to the claims, and to the drawings, in which like numerals refer to like elements, and wherein:

FIG. 1 is a schematic of one preferred process of the invention, and

FIG. 2 is a schematic of another preferred process of the invention.

Claims

1. A composition with a Mohs hardness of at least 6.0, wherein said composition is comprised of at least 30 weight percent of spinel crystals, at least 10 weight percent of glass, and less than about 10 weight percent of ferrometasilicate, wherein said composition comprises at least 95 weight percent of particles with a particle size smaller than about 2.0 millimeters, wherein at least about 70 weight percent of said particles have a particle shape selected from the group consisting of blocky particle shape, pyramidal particle shape, and mixtures thereof, and wherein: (a) at least 20 weight percent of said spinel crystals are equiaxed spinel crystals,(b) the weight/weight ratio of said spinel crystals to said glass is at least 1.2/1,(c) said composition has a melting point in excess of 1300 degrees Celsius, and(d) said composition has a density of from about 3.0 to 4.5.

2. The composition as recited in claim 1, wherein said composition is an abrasive composition.

3. The composition as recited in claim 1, wherein said composition is comprised of at least about 35 weight percent of spinel crystals.

4. The composition as recited in claim 1, wherein said composition is comprised of at least 25 weight percent of glass.

5. The composition as recited in claim 1, wherein said composition is comprised of less than 0.2 weight percent of crystalline silica.

6. The composition as recited in claim 1, wherein at least about 80 weight percent of said particles have a particle shape selected from the group consisting of blocky particle shape, pyramidal particle shape, and mixtures thereof.

7. The composition as recited in claim 1, wherein said spinel crystals are comprised of equiaxed spinel crystals and dendritic spinel crystals.

8. The composition as recited in claim 1, wherein said composition is comprised of at least about 40 weight percent of said equiaxed spinel crystals.

9. The composition as recited in claim 1, wherein said composition is comprised of from about 50 to about 80 weight percent of said spinel crystals and from about 20 to about 50 weight percent of said glass.

10. The composition as recited in claim 7, wherein at least about 20 weight percent of said spinel crystals are dendritic spinel crystals.

11. The composition as recited in claim 7, wherein the weight/weight ratio of said dendritic spinel crystals to said equiaxed spinel crystals is at least about 1/5.

12. The composition as recited in claim 1, wherein said equiaxed spinel crystals have a maximum dimension of from about 10 to about 70 microns.

13. The composition as recited in claim 1, wherein said spinel crystals are comprised of chromite crystals.

14. The composition as recited in claim 1, wherein said spinel crystals are comprised of iron.

15. The composition as recited in claim 14, wherein at least about 50 weight percent of said composition is comprised of iron-containing spinel crystals.

16. The composition as recited in claim 14, wherein at least about 60 weight percent of said composition is comprised of iron-containing spinel crystals.

17. The composition as recited in claim 1, wherein said composition is comprised of from about 1 to about 20 weight percent of a calcium iron silicate.

18. The composition as recited in claim 17, wherein said calcium iron silicate is crystalline calcium iron silicate.

19. The composition as recited in claim 1, wherein the weight/weight ratio of said spinel crystals to said glass is at least about 1.4/1.

20. The composition as recited in claim 1, wherein the weight/weight ratio of said spinel crystals to said glass is at least about 1.5/1.

21. The composition as recited in claim 1, wherein said composition is comprised of less than about 5 weight percent of ferrometasilicate.

22. The composition as recited in claim 1, wherein said composition is comprised of less than about 1 weight percent of ferrometasilicate.

23. The composition as recited in claim 1, wherein said composition has a Mohs hardness of from about 6 to about 9.

24. The composition as recited in claim 1, wherein said composition has a Mohs hardness of from about 6 to about 8.

25. The composition as recited in claim 1, wherein said composition is prepared by a process in which from about 40 to about 80 weight percent of electric arc furnace dust is mixed with from about 10 to about 40 weight percent of glass in a ratio of from about 2/1 to about 4.5/1 to prepare a mixture, and wherein said mixture is melted at a temperature of less than about 1430 degrees Celsius.

26. The composition as recited in claim 25, wherein said mixture is melted at a temperature of from about 1260 to about 1320 degrees Celsius.

27. The composition as recited in claim 1, wherein said composition is comprised of less than about 10 weight percent of particles smaller than 125 microns.

28. The composition as recited in claim 1, wherein said composition is comprised of at least about 50 weight percent of particles ranging in size from about 45 to about 125 microns.

29. The composition as recited in claim 1, wherein said composition has a density of from about 3.0 to about 4.1 grams per cubic centimeter.

30. The composition as recited in claim 1, wherein said composition is comprised of from about 20 to about 40 weight percent of an iron compound selected from the group consisting of ferrous oxide, ferric oxide, iron-containing spinel, calcium iron silicate, and mixtures thereof.

31. The composition as recited in claim 1, wherein said composition is comprised of less than about 75 weight percent of crystalline material.

32. A composition with a Mohs hardness of at least 6.0, wherein said composition is comprised of at least 30 weight percent of spinel crystals, at least 10 weight percent of glass, and less than about 10 weight percent of ferrometasilicate, wherein said composition comprises at least 95 weight percent of particles with a particle size smaller than about 2.0 millimeters, wherein at least about 70 weight percent of said particles have a particle shape selected from the group consisting of blocky particle shape, pyramidal particle shape, and mixtures thereof, and wherein: (a) at least 20 weight percent of said spinel crystals are dendritic spinel crystals,(b) the weight/weight ratio of said spinel crystals to said glass is at least 1.2/1,(c) said composition has a melting point in excess of 1300 degrees Celsius; and(d) said composition has a density of from about 3.0 to 4.5.

33. The composition as recited in claim 7, wherein the weight/weight ratio of said dendritic spinel crystals to said equiaxed spinel crystals is from about 1/1 to about 3/1.