Abrasives can be broadly classified into natural and synthetic abrasives based on their origin and composition. Natural abrasives are obtained directly from nature whereas synthetic abrasives are manufactured through industrial processes.
Natural Abrasives
Some common examples of natural abrasives include sand, emery, corundum, diamond, garnet and others. Sand is one of the most abundantly available natural abrasives found mainly in desert areas. Abrasives has been used for applications like grinding, smoothing, polishing etc. for centuries. Emery is a naturally occurring opaque black rock that consists of corundum mixed with magnetite and other iron compounds. Due to its hardness, it is used for precision grinding applications. Corundum, an aluminum oxide mineral form of which is ruby and sapphire, has greater hardness than emery and is used for grinding and polishing of hard materials. Diamond, being the hardest natural material, finds application in drilling, sawing andprecision machining of abrasion resistant materials. Garnet, a family of silicate minerals, is also used as an effective abrasive.
Synthetic Abrasives
When natural abrasives cannot meet industrial production demands due to shortage or limited properties, synthetic abrasives are produced. Common synthetic abrasives include aluminum oxide, silicon carbide, tungsten carbide, cubic boron nitride, diamond (synthetic), corundum (synthetic) and more.
Aluminum oxide, also known as corundum or emery, is one of the most widely used synthetic abrasives owing to its hardness, durability and reasonable cost. It is commercially produced through electrofusion or fused aluminum oxide process. Silicon carbide possesses high hardness and strength even at elevated temperatures making it suitable as an abrasive for non-ferrous metals, plastics and composites. Tungsten carbide, with hardness second only to diamond, is primarily used for machining hard ferrous alloys and cast irons. Synthetic diamond and cubic boron nitride share properties similar to their natural counterparts and are utilized where high hardness and heat resistance are critical.
Classification Based on Form
Abrasives can be classified according to their physical form as primary abrasives and bonded abrasives.
Primary Abrasives
Primary abrasives such as natural garnet sand, aluminum oxide grit and silicon carbide are used in their raw, unbonded form. Due to the lack of binding, they provide the flexibility to change the grade and type easily. However, ensuring an even cut and controlling the pressure can be difficult.
Bonded Abrasives
Bonded abrasives comprise of abrasive grains that are bonded together using a bonding medium like resin, clay or glass to form different shapes such as belts, discs, cups, sticks etc. This bonding confers strength to the abrasive and also helps in uniform abrasive action. The bonds can be either vitrified (heat-treated) or resinoid (room temperature cured plastic resin). Vitrified bonds are heat resistant while resinoid bonds can dress intricate surfaces. Common bonded abrasive tools include grinding wheels, sandpapers, honing stones etc.
Applications of Abrasives
The versatile properties of abrasives have made them indispensable in a wide range of applications from simple polishing to precision grinding. Here are some of their major applications:
- Surface finishing: Abrasives are extensively used for finishing operations like deburring, smoothing, buffing, polishing in virtually all manufacturing industries.
- Machining: Grinding is the main abrasive machining process employed for high precision shaping and finishing of metallic and non-metallic workpieces. Abrasives are also used for scrubbing, sharpening, cutting and cleaning in various sub-processes.
- Abrasive jet machining: High pressure abrasive waterjets or abrasive airjets are used to cut hard and brittle materials like ceramics, glass and composites.
- Abrasive blasting: Projected abrasive particles helps effective surface cleaning and surface preparation works like peening and deburring. It also aids in non-slip paint application and texturing.
- Drilling and cutting: Diamond and CBN wheels are important for drilling and cutting hard and heat sensitive materials like stone, glass and carbides.
- Woodworking: Abrasive papers and discs are essential for wood polishing, finishingwood furniture and flooring works.
- Other industries: Abrasives play a crucial role in metal casting, electronics, ceramics, plastics, automotive, shipbuilding and healthcare sectors as well.
This brings to an end the 1150 word article on Abrasives covering its major types, classification and applications in industries. Abrasives have become a fundamental material for diverse machining and finishing processes due to their hardness, wear resistance and versatile application range. Their continuous development expands the boundaries of precision manufacturing.
Get this report in Japanese Language-研磨剤
Get this report in Korean Language-연마제
About Author-
Money Singh is a seasoned content writer with over four years of experience in the market research sector. Known for her strong SEO background, she skillfully blends SEO strategies with insightful content. Her expertise spans various industries, including food and beverages, biotechnology, chemical and materials, defense and aerospace, consumer goods, etc. (https://www.linkedin.com/in/money-singh-590844163)
