Abrasive grain including manganese oxide therein are provided. The inclusion of manganese oxide can be utilized to reduce the transition temperature of transitional alumina(s) to alpha alumina(s), during the formation of the abrasive grain. Further, manganese oxide presence can be utilized to generate sintered abrasive grain having a submicrometer, faceted microstructure. The abrasive grain are useful in abrasive articles such as coated abrasives, three-dimensional, low density abrasives, and bonded abrasives.
This is a continuation of U.S. Ser. No. 08/459,548, filed Jun. 2, 1995, now U.S. Pat. No. 5,690,707, which is a continuation of U.S. Ser. No. 08/248,042, filed Aug. 1, 1994, now abandoned, which is a continuation of U.S. Ser. No. 08/173,401, filed Dec. 21, 1993, now abandoned, which in turn is a continuation-in-part of U.S. Ser. No. 07/995,964, filed Dec. 23, 1992, now abandoned.
A method for making a polymeric blast media, and a product of this method. The first step involves blending a melamine compound with a cellulosic material and compression molding said first blend to produce a compression molded first blend. This first blend is then cooled and then ground. In the next step of this method, a urea compound is blended with a nano-clay material to produce a second blend and compression molded. This compression molded second blend is then ground to produce a particulate second blend. The particulate first blend is then blended with the particulate second blend. A blast media product of this method is also disclosed.
Sintered alpha alumina-based abrasive particles comprising alpha alumina, Gd.sub.2 O.sub.3, and ZnO, and methods of making the same. The abrasive particles can be incorporated, for example, into a variety of abrasive articles, including bonded abrasives, coated abrasives, nonwoven abrasives, and abrasive brushes.
