Spray drying methods of making agglomerate abrasive grains and abrasive articles

A method for making a plurality of agglomerate abrasive grains, the method comprising:

• spray drying a slurry using a spray-dryer to provide a plurality of precursor agglomerate abrasive grains, the slurry comprising:
• first mineral particles having a Moh's hardness of greater than or equal to about 5;
• glass frit;
• solvent;
• and
• at least one of solvent-dispersible binder material or solvent-soluble binder material,
• said spray-dryer having an inlet temperature of about 90° C. to about 400° C. and an outlet temperature of about 40° C. to about 250° C.;
• mixing said plurality of precursor agglomerate abrasive grains with second mineral particles;
• and
• heating the mixture of said plurality of precursor agglomerate abrasive grains and said second mineral particles to at least one temperature such that the glass frit at least partially fuses to provide a plurality of agglomerate abrasive grains each comprised of said first mineral particles bonded together via glass binder material,
• wherein the glass frit has a softening point and the first mineral particles have at least one of a softening point, melting point, or decomposition temperature and wherein the lower of the at least one of a softening point, melting point, or decomposition temperature of the first mineral particles is greater than the softening point of the glass frit.

A method for making a plurality of agglomerate abrasive grains, the method comprising:

• spray drying a slurry using a spray-dryer to provide a plurality of precursor agglomerate abrasive grains, the slurry comprising:
• first mineral particles having a Moh's hardness of greater than or equal to about 5;
• glass frit;
• solvent;
• and
• at least one of solvent-dispersible binder material or solvent-soluble binder material,
• said spray-dryer having an inlet temperature of about 90° C. to about 400° C. and an outlet temperature of about 40° C. to about 250° C.;
• mixing said plurality of precursor agglomerate abrasive grains with second mineral particles;
• and
• heating the mixture of said plurality of precursor agglomerate abrasive grains and said second mineral particles to at least one temperature such that the glass frit at least partially fuses to provide a plurality of agglomerate abrasive grains each comprised of said first mineral particles and said second mineral particles bonded together via glass binder material,
• wherein the glass frit has a softening point and the first mineral particles have at least one of a softening point, melting point, or decomposition temperature and wherein the lower of the at least one of a softening point, melting point or decomposition temperature of the first mineral particles is greater than the softening point of the glass frit,
• wherein the glass frit has a softening point and the second mineral particles have at least one of a softening point, melting point, or decomposition temperature and wherein the lower of the at least one of a softening point, melting point, or decomposition temperature of the second mineral particles is greater than the softening point of the glass frit.

A method for making an abrasive article, the method comprising:

• spray drying a slurry to provide a plurality of precursor agglomerate abrasive grains, the slurry comprising:
• first mineral particles having a Moh's hardness of greater than or equal to about 5;
• glass frit;
• solvent;
• and
• at least one of solvent-dispersible binder material or solvent-soluble binder material;
• heating the plurality of precursor agglomerate abrasive grains to at least one temperature such that the glass frit at least partially fuses to provide a plurality of agglomerate abrasive grains each comprised of said first mineral particles bonded together via glass binder material;
• and
• combining at least a portion of the plurality of the agglomerate abrasive grains with abrasive article binder material to provide said abrasive article.

A method for making a coated abrasive article, the method comprising:

• spray drying a slurry to provide a plurality of precursor agglomerate abrasive grains, the slurry comprising:
• first mineral particles having a Moh's hardness of greater than or equal to about 5;
• glass frit;
• solvent;
• and
• at least one of solvent dispersible binder material or solvent-soluble binder material;
• heating the plurality of precursor agglomerate abrasive grains to at least one temperature such that the glass frit at least partially fuses to provide a plurality of agglomerate abrasive grains each comprised of said first mineral particles bonded together via glass binder material;
• and
• applying an abrasive layer comprising at least a portion of the plurality of agglomerate abrasive grains dispersed within abrasive article binder material to a major surface of a backing to provide said coated abrasive article.