Overview of Coated Abrasives and Application Advantages and Disadvantages

Coated abrasives are tools made by bonding abrasives to flexible materials like cloth or paper using adhesives?(glues), making them suitable for grinding and polishing.

These include various forms such as rolls, sheets, belts, discs, and customized-shaped products. These can be made from substrates like cloth, paper,?or?non-woven fabric,

They are used extensively in metal, wood, ceramics, plastics, leather, rubber, and non-metallic materials like paint and putty for grinding, polishing, and sanding.

Components of Coated Abrasives

Coated abrasives comprise three main elements: the substrate, the abrasive, and?the adhesive.

1. Substrate: This forms the carrier for the abrasive and adhesive and is the primary determinant of the abrasive's flexibility. Substrate materials for coated abrasives include paper, cloth, steel paper, composite substrates, non-woven fabric, polyester films, and more. These substrates must undergo specialized treatment to enhance their physical and mechanical properties, ensuring they meet the requirements for adhesive bonding and grinding processes. Substrate treatments can be categorized into non-water-resistant and water-resistant treatments, with further variations like soft treatment, high-permeability treatment, oil-resistance treatment, and anti-static?treatment based on the specific grinding requirements.

2. Abrasive: The abrasive is a material with high hardness and strength, essential for manufacturing abrasive tools or direct grinding and polishing. Abrasives can be categorized into two main types: natural and synthetic. Abrasives must possess certain essential properties such as adequate hardness, strength, suitable fracturing characteristics, self-sharpening ability, and chemical or thermal stability.

3. Adhesive: The adhesive bonds?the abrasive to the substrate, providing the abrasive tool with its shape and strength. Adhesives in coated abrasives typically consist of substrate treatment agents, base adhesives, and additional adhesives.

- Substrate Treatment Agents: These agents aim to improve the physical and mechanical properties of the substrate, ensuring proper adhesive bonding and grinding performance. Depending on the specific requirements of the product, substrate treatment can be?either water-resistant?or non-water-resistant and the treatment agents should be aligned?accordingly.

- Base Adhesives: Base adhesives form the coating that bonds abrasives to the substrate.

- Additional Adhesives: Additional adhesives are applied over the already?bonded abrasive grains to further enhance their bonding strength, ensuring the abrasive grains withstand the pressures and impacts during grinding without detaching from the substrate.

Common Varieties of Abrasives Used in Coated Abrasives

1. Brown Fused Alumina (A, WA): Composed primarily of α-Al2O3, brown fused alumina exhibits a brown or brownish-red appearance. It boasts high hardness, good toughness, and the ability to withstand substantial pressure. Its important features include resistance to high temperatures?and?corrosion, while also having excellent chemical stability. Brown fused alumina is widely used in the grinding of high-tensile-strength metals like carbon steel, hard bronze, alloy steel, and malleable cast iron.

2. White Fused Alumina (A, WA): White fused alumina, also primarily composed of α-Al2O3, but appears white in color. It possesses higher hardness?than brown fused alumina but is more brittle with better sharpness. It is mainly used for fine and precision grinding of hardened steel, and alloy steel, as well as for thread and gear grinding. It also finds applications?in precision casting and advanced refractories.

3. Silicon Carbide (C, GC): Silicon carbide comes in two main varieties: black and green. It primarily consists of SiC and appears black?in color. It is characterized by high hardness, brittleness, and excellent sharpness. Silicon carbide does not react with acidic substances but can be decomposed by alkaline oxide melts. Black silicon carbide, with its higher hardness and greater brittleness compared to brown fused alumina, is suitable for processing low?tensile?strength metals and nonmetallic materials like gray cast iron, brass, lead, and aluminum, as well as hard, brittle nonmetallic materials such as glass and ceramics.

Green silicon carbide, which is purer, harder, and more brittle than black silicon carbide, is suitable for machining hard and brittle materials like hard alloys, optical glass, and agate, and is widely used for precision grinding of gauges, cutting tools, and molds, as well as for honing various cylinders.

4.?Zirconia Alumina (ZA): Zirconia alumina consists mainly of α-Al2O3 and AI2O3-Zr eutectic crystals. It appears grayish?white or grayish?brown and exhibits excellent toughness and wear resistance. It is suitable for high-speed heavy-load grinding and the machining of difficult-to-machine metal materials such as cast steels and alloy steels and is particularly well?suited for the grinding of titanium alloys, heat-resistant alloys, and stainless steel.

Learn More:https://www.kamel.com.cn/?p=22165

#kamel #Abrasives #manufacturer #Grinding #Flap #wholesaler