An abrasive is a material, usually granulated, that is used to abrade or polish, by friction, hard substances such as metals, glass, etc. lapping, sandblasting, grinding, scraping, refining, or cutting. These materials must have a high hardness (7 or more on the Mohs scale) to be able to perform these functions. They are used in all types of processes: industrial and artisanal. From the point of view of tribology, they are distinguished from corrosive materials in that they do not require mechanical force to produce wear or reduction of the material.
In industrial use, polishing machines, belt sanders, grinders, grinders, miter saws or circular saws that use cutting or grinding discs are used.
History
The lithic manufacture of axes and other stone instruments already required us to compare and know the relative hardness of this type of materials. There is reason to think that some device for polishing and sawing stones was used as early as 4,000 BC. C. in Egypt, although the real expansion of the use of abrasives coincided with the beginning of metallurgy in the Middle East around 2000 BC. C. The first confirmed use of abrasives to grind metal is dated to 1,500 BC. C., when a steel dagger was found next to a whetstone.[3].
Classes
Abrasives can be natural (diamonds, sandstone, garnet, white or brown corundum, pumice or pumice, novaculite, silica sand or silica / quartz, not recommended because it produces silicosis, chert, flint, diatomite, micronized tripoli, also called rotten stone or rotten stone, etc.)[4] and artificial (borazon, glass microspheres, ceramic shot, plastic shot, vegetable abrasive -almond and/or walnut shell-, steel shot and stainless steel shot, synthetic diamonds, emery or colundite wheels, bands, crowns and abrasive discs...).
Coated abrasives include abrasive grains cemented onto a cloth, polyester or vulcanized fiber paper, in very diverse formats: sandpaper sheets or strips, cloth sheets or emery rolls, sponges and sanding fans...
Bonded abrasives use fine-grained materials, such as corundum or silicon carbide. They are vitrified grinding wheels, sharpening stones or resin, rubber or shellac wheels.
Loose grain abrasives are mainly used in the manufacture of polishing products, cleaners or brighteners. Garnet, flint, pumice, feldspar or quartz sand, for example.
abrasive stones
Introduction
An abrasive is a material, usually granulated, that is used to abrade or polish, by friction, hard substances such as metals, glass, etc. lapping, sandblasting, grinding, scraping, refining, or cutting. These materials must have a high hardness (7 or more on the Mohs scale) to be able to perform these functions. They are used in all types of processes: industrial and artisanal. From the point of view of tribology, they are distinguished from corrosive materials in that they do not require mechanical force to produce wear or reduction of the material.
In industrial use, polishing machines, belt sanders, grinders, grinders, miter saws or circular saws that use cutting or grinding discs are used.
History
The lithic manufacture of axes and other stone instruments already required us to compare and know the relative hardness of this type of materials. There is reason to think that some device for polishing and sawing stones was used as early as 4,000 BC. C. in Egypt, although the real expansion of the use of abrasives coincided with the beginning of metallurgy in the Middle East around 2000 BC. C. The first confirmed use of abrasives to grind metal is dated to 1,500 BC. C., when a steel dagger was found next to a whetstone.[3].
Classes
Abrasives can be natural (diamonds, sandstone, garnet, white or brown corundum, pumice or pumice, novaculite, silica sand or silica / quartz, not recommended because it produces silicosis, chert, flint, diatomite, micronized tripoli, also called rotten stone or rotten stone, etc.)[4] and artificial (borazon, glass microspheres, ceramic shot, plastic shot, vegetable abrasive -almond and/or walnut shell-, steel shot and stainless steel shot, synthetic diamonds, emery or colundite wheels, bands, crowns and abrasive discs...).
Coated abrasives include abrasive grains cemented onto a cloth, polyester or vulcanized fiber paper, in very diverse formats: sandpaper sheets or strips, cloth sheets or emery rolls, sponges and sanding fans...
Abrasive discs allow higher performance with minimal investment. They are composed of cutting material (abrasive grain) that covers the surface of the disc, a binder for them and a reinforced mesh, generally made of fiberglass.[5].
They are also classified by their greater or lesser hardness. To do this, they are assessed according to various scales, the most used of which is the Mohs scale, established in 1820 by the German mineralogist Friedrich Mohs. Another factor, important if it is grinding wheels or sharpening wheels), is its granulometry, preferably high. For its application, the abrasive grain must be fixed with a binder on a flexible or semi-flexible support, or concentrated on sharpening wheels.
Among the best performing abrasive materials are aluminum oxide (alumina), well suited to sanding hard materials such as steel, carbon, alloy steels, bronze and hard woods; sand, silicon carbide (also called carburindon) ideal for sanding non-ferrous metals (aluminum, brass, magnesium, titanium, etc.), rubber, glass, plastics, fibrous woods, enamels and other relatively soft materials, due to its ability to penetrate and cut quickly with low pressure; borazon (cubic boron nitride) and diamond. Other materials are cerium oxide, tin oxide, boron carbide, tungsten carbide and other crystalline substances of an inorganic nature.
Another example of an abrasive is emery, composed mostly of aluminum oxide. It is used to make sandpaper and for high-pressure water cutting processes. The basic elements to consider in the cutting operation and performance of emery wheels are the type and size of the grain, sandpaper or binder, its hardness and its structure.[6].
Abrasives are used to make lenses in optics, in gem jewelry, in stonemasonry to work stone, granite and marble, in metallurgy to sand metals, and in carpentry to sand hard and soft woods. Also to achieve the surface finish or improvement in adhesion of metal surfaces, for deburring and matting of glass, for sandblasting" of parts (removal of rust, scale and scale on metal surfaces, discolorations and pressure cleaning of surfaces), preparation of surfaces for painting, anodizing or galvanizing and after heat treatments, aesthetic chrome plating and coatings, anti-corrosion treatments, shot peening*...
Cost reduction
Having the right abrasive is not enough. It is also necessary to perfectly adjust all the components involved in the sanding process, because a cost reduction of up to 40% has been shown to be a realistic goal. It can be achieved by reducing the number of rejects, cycle times and machine downtime.
All process indices or parameters (such as contact pulley, feed speed, cutting speed and lubricant) can be optimized to improve the performance of the abrasive in use. Only by taking all these factors into account can a sustainable cost reduction be achieved.
Grain
The grit&action=edit&redlink=1 "Grit (abrasive) (not yet written)") is the element that does the cutting and grinding work. To know how to choose a grain, it is important to consider its size (fine or large) and its type. There are natural and manufactured grains, among the natural ones are diamonds, emery stones, sandstones, corundum and quartz. They generally contain large percentages of impurities which could make the cutting and grinding action difficult. Manufactured grains are made by controllable methods in electric arc furnaces since the quality and characteristics of a wheel must meet certain grinding requirements. Materials such as aluminum oxide, silicon carbide, zirconium and ceramic materials are used.
Since the grain is the primary element of the abrasive, it is important to consider the size that will be used. This is determined by the number of mesh per linear inch of the sieve through which the grain in question passes.
The use of coarse grain abrasives is used for soft materials, for quick grinding, when the finish is not important and to cover large contact areas.
On the contrary, fine grain is used for hard, brittle and brittle materials such as steels, cemented carbides and glass, for fine finishes, for small contact areas and to maintain small profiles.
sandpaper
The sandpaper or binder is the backing material that holds the grain attached to the abrasive material. Various types of binders are used, from gypsum or ceramic in some abrasive stones, to synthetic materials. It is important to consider the hardness of the material; This is the limit of strength with which the bonding material holds the grains in the shape of a wheel. It is also a measure of the strength of the compound stress of the bond material and grains with the stresses of grinding. This can be indicated by letters, starting with A, B, C, D, etc. as the softest and ending with X, Y, Z as the hardest.
Find more "abrasive stones" in the following countries:
[1] ↑ ASALE, RAE-. «abrasivo, abrasiva (acepción 2) | Diccionario de la lengua española». «Diccionario de la lengua española» - Edición del Tricentenario. Consultado el 8 de diciembre de 2024.: https://dle.rae.es/abrasivo
[4] ↑ Maldonado, Yandri (2021). «Materiales abrasivos: Tipos, propiedades, características y usos». Geología web. Consultado el 21 de diciembre de 2021.: https://geologiaweb.com/materiales/abrasivos/
Bonded abrasives use fine-grained materials, such as corundum or silicon carbide. They are vitrified grinding wheels, sharpening stones or resin, rubber or shellac wheels.
Loose grain abrasives are mainly used in the manufacture of polishing products, cleaners or brighteners. Garnet, flint, pumice, feldspar or quartz sand, for example.
Abrasive discs allow higher performance with minimal investment. They are composed of cutting material (abrasive grain) that covers the surface of the disc, a binder for them and a reinforced mesh, generally made of fiberglass.[5].
They are also classified by their greater or lesser hardness. To do this, they are assessed according to various scales, the most used of which is the Mohs scale, established in 1820 by the German mineralogist Friedrich Mohs. Another factor, important if it is grinding wheels or sharpening wheels), is its granulometry, preferably high. For its application, the abrasive grain must be fixed with a binder on a flexible or semi-flexible support, or concentrated on sharpening wheels.
Among the best performing abrasive materials are aluminum oxide (alumina), well suited to sanding hard materials such as steel, carbon, alloy steels, bronze and hard woods; sand, silicon carbide (also called carburindon) ideal for sanding non-ferrous metals (aluminum, brass, magnesium, titanium, etc.), rubber, glass, plastics, fibrous woods, enamels and other relatively soft materials, due to its ability to penetrate and cut quickly with low pressure; borazon (cubic boron nitride) and diamond. Other materials are cerium oxide, tin oxide, boron carbide, tungsten carbide and other crystalline substances of an inorganic nature.
Another example of an abrasive is emery, composed mostly of aluminum oxide. It is used to make sandpaper and for high-pressure water cutting processes. The basic elements to consider in the cutting operation and performance of emery wheels are the type and size of the grain, sandpaper or binder, its hardness and its structure.[6].
Abrasives are used to make lenses in optics, in gem jewelry, in stonemasonry to work stone, granite and marble, in metallurgy to sand metals, and in carpentry to sand hard and soft woods. Also to achieve the surface finish or improvement in adhesion of metal surfaces, for deburring and matting of glass, for sandblasting" of parts (removal of rust, scale and scale on metal surfaces, discolorations and pressure cleaning of surfaces), preparation of surfaces for painting, anodizing or galvanizing and after heat treatments, aesthetic chrome plating and coatings, anti-corrosion treatments, shot peening*...
Cost reduction
Having the right abrasive is not enough. It is also necessary to perfectly adjust all the components involved in the sanding process, because a cost reduction of up to 40% has been shown to be a realistic goal. It can be achieved by reducing the number of rejects, cycle times and machine downtime.
All process indices or parameters (such as contact pulley, feed speed, cutting speed and lubricant) can be optimized to improve the performance of the abrasive in use. Only by taking all these factors into account can a sustainable cost reduction be achieved.
Grain
The grit&action=edit&redlink=1 "Grit (abrasive) (not yet written)") is the element that does the cutting and grinding work. To know how to choose a grain, it is important to consider its size (fine or large) and its type. There are natural and manufactured grains, among the natural ones are diamonds, emery stones, sandstones, corundum and quartz. They generally contain large percentages of impurities which could make the cutting and grinding action difficult. Manufactured grains are made by controllable methods in electric arc furnaces since the quality and characteristics of a wheel must meet certain grinding requirements. Materials such as aluminum oxide, silicon carbide, zirconium and ceramic materials are used.
Since the grain is the primary element of the abrasive, it is important to consider the size that will be used. This is determined by the number of mesh per linear inch of the sieve through which the grain in question passes.
The use of coarse grain abrasives is used for soft materials, for quick grinding, when the finish is not important and to cover large contact areas.
On the contrary, fine grain is used for hard, brittle and brittle materials such as steels, cemented carbides and glass, for fine finishes, for small contact areas and to maintain small profiles.
sandpaper
The sandpaper or binder is the backing material that holds the grain attached to the abrasive material. Various types of binders are used, from gypsum or ceramic in some abrasive stones, to synthetic materials. It is important to consider the hardness of the material; This is the limit of strength with which the bonding material holds the grains in the shape of a wheel. It is also a measure of the strength of the compound stress of the bond material and grains with the stresses of grinding. This can be indicated by letters, starting with A, B, C, D, etc. as the softest and ending with X, Y, Z as the hardest.
Find more "abrasive stones" in the following countries:
[1] ↑ ASALE, RAE-. «abrasivo, abrasiva (acepción 2) | Diccionario de la lengua española». «Diccionario de la lengua española» - Edición del Tricentenario. Consultado el 8 de diciembre de 2024.: https://dle.rae.es/abrasivo
[4] ↑ Maldonado, Yandri (2021). «Materiales abrasivos: Tipos, propiedades, características y usos». Geología web. Consultado el 21 de diciembre de 2021.: https://geologiaweb.com/materiales/abrasivos/