An abrasive grain is disclosed and may include a body. The body may define a length (l), a height (h), and a width (w). In a particular aspect, the length is greater than or equal to the height and the height is greater than or equal to the width. Further, in a particular aspect, the body may include a primary aspect ratio defined by the ratio of length:height of at least about 2:1. The body may also include an upright orientation probability of at least about 50%.

A precursor of an alumina sintered compact including aluminum, yttrium, and at least one metal selected from iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium. The aluminum content is 98.0% by mass or more as an oxide (Al2O3) in 100% by mass of the precursor of an alumina sintered compact; the yttrium content is 0.01 to 1.35 parts by mass as an oxide (Y2O3) based on 100 parts by mass of the content of the aluminum as an oxide; the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as an oxide based on 100 parts by mass of the content of aluminum as an oxide; and the aluminum is contained as α-alumina. Also disclosed is an alumina sintered compact, and a method for producing an alumina sintered compact and for producing abrasive grains.

A method for producing abrasive particles includes: i) providing a starting mixture which contains at least aluminum hydroxide and which can be converted at least into aluminum oxide by a heat treatment, ii) extruding the starting mixture in order to form an extrudate, iii) separating the extrudate into intermediate particles, and iv) heat-treating the intermediate particles. The intermediate particles are converted into abrasive particles which contain aluminum oxide, and the starting mixture is pressed through at least one nozzle element with a plurality of substantially parallel nozzle channels. The nozzle channels are preferably arranged in a mutually spaced manner over the course of the extrusion process, and the extrudate has a spiral or hollow cylindrical shape at least in some sections.

A method for forming an abrasive article via an additive manufacturing technique including forming a layer of powder material comprising a precursor bond material and abrasive particles, compacting at least a portion of the layer to form a compacted layer, binding at least a portion of the compacted layer, and repeating the steps of forming, compacting, and binding to form a green body abrasive article.

A method of making elongated abrasive particles includes five steps. Step 1) includes providing a mold having parallel linear grooves, partially interrupted at predetermined intervals by transverse obstructions. Step 2) includes filling the parallel linear grooves with a flowable abrasive particle precursor composition. Step 3) includes at least partially drying the flowable abrasive particle precursor composition to form an at least partially dried abrasive particle precursor composition. Step 4) includes separating that composition from the mold, thereby forming elongated precursor abrasive particles having a shape corresponding to portions of the parallel linear grooves disposed between the transverse obstructions. At least one of the first and second opposite ends of the elongated precursor abrasive particles comprises both a molded portion and a fractured portion. Step 5) converts the elongated precursor abrasive particles into elongated abrasive particles. Elongated abrasive particles preparable by the method and abrasive articles containing them are also disclosed.

A process for solid lubricant filler powder used in abradable coating manufacture comprising mixing a bentonite clay and a hexagonal boron nitride powder to form a mixture of the bentonite clay and the hexagonal boron nitride powder; consolidating the bentonite clay and the hexagonal boron nitride powder to form a composite material; heat treating the composite material to at least 500 degrees centigrade; breaking up the composite material into a variety of sizes; and segregating the composite material to produce a final product of free flowing, low dust powder of composite hexagonal boron nitride and calcined bentonite.

The invention relates to a method for producing an alumina based abrasive particle (1), comprising at least the following steps: forming a sol as a solution or dispersion of alumina particles, gelling the sol by adding gelling agents, forming shaped bodies from the gel using an additive procedure, drying and firing the shaped bodies while retaining the previously achieved geometry of the abrasive particles. Hereby, it is provided that an optically binding binder is added to the sol and/or the gel, the gel is applied additively layer by layer and the binder is set using electromagnetic radiation so as to form the shaped bodies. The produced abrasive particle may be formed, in particular, by six intersecting or overlapping triangular volume regions.

An abrasive grain is disclosed and may include a body. The body may define a length (l), a height (h), and a width (w). In a particular aspect, the length is greater than or equal to the height and the height is greater than or equal to the width. Further, in a particular aspect, the body may include a primary aspect ratio defined by the ratio of length:height of at least about 2:1. The body may also include an upright orientation probability of at least about 50%.

A structured abrasive article comprises a backing having first and second opposed major surfaces and an abrasive layer securely bonded to the first major surface of the backing. The abrasive layer comprises shaped abrasive composites. Each shaped abrasive composite has four sides, a height, and abase that faces the first major surface of the backing. The shaped abrasive composites have an average height of 410 to 650 microns and an average side length at the base of 550 to 1450 microns. The shaped abrasive composites comprise non-magnetizable shaped abrasive platelets that have an average side length of 150 to 350 microns and an average thickness of 40 to 120 microns. Methods of making and using are also disclosed.

An abrasive article comprises elongated abrasive particles retained in at least one binder. The elongated abrasive particles comprise a ceramic body bounded by at least two longitudinally-oriented contiguous surfaces and first and second ends separated by the at least two longitudinally-oriented surfaces. At least one of the first and second ends comprises both a molded portion and a fractured portion.