A fused grain having the following chemical composition in percent by weight in relation to the oxides: ZrO.sub.2: 16% to 30%, provided that HfO.sub.2<2%, Al.sub.2O.sub.3: percentage needed to bring the total to 100%, Cr.sub.2O.sub.3: ≥0.2%, TiO.sub.2: ≥0.5%, Cr.sub.2O.sub.3+TiO.sub.2: <7%, other elements: <3%, provided that SiO.sub.2+CaO+MgO<1.5%.

The present disclosure provides methods of making a vitreous bond abrasive article and a metal bond abrasive article. The methods include sequential steps. Step a) includes a subprocess including sequentially: i) depositing a layer of loose powder particles in a confined region; and ii) selectively applying heat via conduction or irradiation, to heat treat an area of the layer of loose powder particles. The loose powder particles include abrasive particles and organic compound particles, as well as vitreous bond precursor particles or metal particles. The layer of loose powder particles has substantially uniform thickness. Step b) includes independently carrying out step a) a number of times to generate an abrasive article preform comprising the bonded powder particles and remaining loose powder particles. Step c) includes separating remaining loose powder particles from the abrasive article preform. Step d) includes heating the abrasive article preform to provide the vitreous bond abrasive article comprising the abrasive particles retained in a vitreous bond material, or to provide the metal bond abrasive article. A method of making a metal bond abrasive optionally includes infusing an abrasive article preform with a molten lower melting metal and solidifying the molten lower melting metal to provide the metal bond abrasive article. The present disclosure further provides a vitreous bond abrasive article precursor and a metal bond abrasive article precursor.

The present disclosure provides methods of making a vitreous bond abrasive article and a metal bond abrasive article. The methods include sequential steps. Step a) includes a subprocess including sequentially: i) depositing a layer of loose powder particles in a confined region; and ii) selectively applying heat via conduction or irradiation, to heat treat an area of the layer of loose powder particles. The loose powder particles include abrasive particles and organic compound particles, as well as vitreous bond precursor particles or metal particles. The layer of loose powder particles has substantially uniform thickness. Step b) includes independently carrying out step a) a number of times to generate an abrasive article preform comprising the bonded powder particles and remaining loose powder particles. Step c) includes separating remaining loose powder particles from the abrasive article preform. Step d) includes heating the abrasive article preform to provide the vitreous bond abrasive article comprising the abrasive particles retained in a vitreous bond material, or to provide the metal bond abrasive article. A method of making a metal bond abrasive optionally includes infusing an abrasive article preform with a molten lower melting metal and solidifying the molten lower melting metal to provide the metal bond abrasive article. The present disclosure further provides a vitreous bond abrasive article precursor and a metal bond abrasive article precursor.

The present disclosure provides methods of making a vitreous bond abrasive article and a metal bond abrasive article. An abrasive article preform is produced by an additive manufacturing sub-process comprising the deposition of a layer of loose powder particles in a confined region and selective heating via conduction or irradiation to heat treat an area of the layer of loose powder particles. The loose powder particles include abrasive particles and organic compound particles, as well as vitreous bond precursor particles or metal particles. The abrasive article preform produced by additive manufacturing is subsequently heated to provide the vitreous bond abrasive article comprising the abrasive particles retained in a vitreous bond material, or to provide the metal bond abrasive article. Also, the methods include receiving, by an additive manufacturing device having a processor, a digital object specifying data for an abrasive article, and generating the abrasive article with the manufacturing device.

The present disclosure provides methods of making a vitreous bond abrasive article and a metal bond abrasive article. An abrasive article preform is produced by an additive manufacturing sub-process comprising the deposition of a layer of loose powder particles in a confined region and selective heating via conduction or irradiation to heat treat an area of the layer of loose powder particles. The loose powder particles include abrasive particles and organic compound particles, as well as vitreous bond precursor particles or metal particles. The abrasive article preform produced by additive manufacturing is subsequently heated to provide the vitreous bond abrasive article comprising the abrasive particles retained in a vitreous bond material, or to provide the metal bond abrasive article. Also, the methods include receiving, by an additive manufacturing device having a processor, a digital object specifying data for an abrasive article, and generating the abrasive article with the manufacturing device.

A polycrystalline abrasive grain includes: a plurality of cBN particles; and a binder that binds the plurality of cBN particles, wherein the binder includes at least one of nitride, carbide, and carbonitride of one selected from a group consisting of a group 4a metal, a group 5a metal, and a group 6a metal in a periodic table, and a content of the binder in the polycrystalline abrasive grain is more than or equal to 5 volume % and less than or equal to 50 volume %.

A polycrystalline abrasive grain includes: a plurality of cBN particles; and a binder that binds the plurality of cBN particles, wherein the binder includes at least one of nitride, carbide, and carbonitride of one selected from a group consisting of a group 4a metal, a group 5a metal, and a group 6a metal in a periodic table, and a content of the binder in the polycrystalline abrasive grain is more than or equal to 5 volume % and less than or equal to 50 volume %.

A shaped abrasive particle including a body comprising a first major surface, a second major surface, and a side surface extending between the first major surface and the second major surface, the body comprising a sharpness-shape-strength factor (3SF) within a range between about 0.7 and about 1.7 and a Shape Index within a range between at least about 0.01 and not greater than about 0.49.

A shaped abrasive particle including a body comprising a first major surface, a second major surface, and a side surface extending between the first major surface and the second major surface, the body comprising a sharpness-shape-strength factor (3SF) within a range between about 0.7 and about 1.7 and a Shape Index within a range between at least about 0.01 and not greater than about 0.49.

The purpose of the present invention is to provide a grinding material which has a superior grinding rate and planarizing accuracy, with the grinding rate being less likely to be reduced over a relatively long period of time. The present invention is directed to a grinding material including a base, a grinding layer overlaid on a front face side of the base and including grinding grains and a binder for the grinding grains, and an adhesion layer overlaid on a back face side of the base, in which the grinding grains are diamond grinding grains, a wear quantity of the grinding layer as determined by a Taber abrasion test is no less than 0.03 g and no greater than 0.18 g, and, an Asker D hardness measured from a front face side of the grinding layer is no less than 80° and no greater than 98°.