Coated Abrasives: Types, Components, and Uses

December 23, 2020

Coated Abrasives: Types, Components, & Uses 

Coated Abrasives Types

Coated abrasive is produced by bonding abrasive grains to backing material or flexible substrate using adhesives. Paper, fabric, vulcanized fiber, and plastic films are widely used as a backing material.

What is Coated Abrasive?

A coated abrasive is an abrasive tool made up of a thin film of abrasive grain attached to a substrate such as paper, fabric, etc. Coated abrasives develop in various shapes such as sheets, discs, rolls, specialties, or belts.

“Coated abrasives are sometimes referred to as "sandpaper," but they are not made with sand and are not backed by paper.“

Applications of Coated Abrasive

In today’s markets such as furniture, lumber, cabinet, boat, automobile, welding, foundry, jewelry, and do-it-yourself markets, The coated abrasives are produced in "jumbo" rolls and then cut into various shapes such as belts, discs, rolls, and sheets for surface treatment and polishing applications.

Sanding rolls and sanding belts, typically for non-precision operation, are commonly coated abrasives for physical applications. These two styles are known as symbolic coated abrasives by the general public.

Other coated abrasives include sanding sheets, sanding discs, flap discs, flap wheels, cross pads, deburring wheels, and many more.

Components of Coated Abrasives 

“Natural gumming + Abrasive grains = Coated abrasive.”

Natural gluing and synthetic abrasive grains are coated abrasive main components. In which abrasive grains contain aluminum oxide, silicon carbide, zirconia alumina, garnet, and emery. While paper, fabric, fiber, and polyester film are common backing materials.

Let’s know each component of coated abrasive in details: 

Abrasive Grains

Coated abrasives are produced using synthetic abrasive grains.  The primary abrasive grains are aluminum oxide, zirconium, ceramic, silicon carbide, and garnet. With the help of calibrated panels, the crude grains are crushed and sorted into grit sizes. 

Then these grains are bound to a backing material by applying several bonding methods. 

Most Popular Abrasive Grains

The most popular abrasive grains structure and uses are given below:

  • Ceramic 

    Ceramic high-density grains are uniform and durable for longer life and sharp cutting. It is a synthetic abrasive material with high performance.

    • Aluminum Oxide

    A rough structure synthetic grain used for high-speed grinding and finishing of metals, wood, and other high tensile strength materials without unnecessary fracturing or shedding.

    • Zirconium

    Zirconium gains are excellent, thick, crystalline & synthetic. Zirconium is a very dense material with a unique self-sharpening feature that gives it a long life in excessive stock removal.

    • Silicon Carbide

    Silicon carbide a rough & sharp synthetic abrasive suitable for non-ferrous materials and non-metallic materials such as concrete, marble, and glass. Silicon carbide cuts faster than any other grain used in coated abrasives.

    • Garnet

    Garnet is an almost sharp but weak bonding structure abrasive grain made of natural aluminum oxide. Its primary use in the wood industry for the finishing of furniture as garnet dulls too quickly.

    What are the different types of backings used in coated abrasives?

    Below are the four significant types of backing materials:

  • Paper: For coated abrasives, highly technical papers are used as substrates. The letters reflecting weight and versatility define them: "A and "B" weights are lightweight and extremely flexible. "C,” "D,” "E,” "F" weights with more strength and less versatility are medium to heavyweight.
  • Cloth: Cloth backings are more reliable than paper backings. Cotton, polyester, and polyester-cotton combinations are significant types of cloth backings. Weight and versatility determine cloth backings. Cloth backing is ideal for applications of heavy-duty grinding and deburring. It provides excellent stability on edge.
  • Fiber: A rigid vulcanized material made from rag stock is fiber backing. For abrasive fiber discs, this backing is commonly used.
  • The mixture’s backing is laminated paper and fabric and is very solid and resistant to shock. For a wide variety of grits and mounting methods, combination backings are usually used.
  • Other Backing Materials: There is also a range of different substrates coated for particular uses, such as nylon fiber or screens. Another substrate that can be used for drying, polishing, or mixing is non-woven nylon impregnated with abrasive grains.

  • Types of Coated Abrasives

    In today's market there are wide collection of coated abrasives available for your product finishing and polishing. It includes a large variety of rolls, discs, flap wheels, and belts. The option that you make should always be based on your needs.

    Below are some of the standard options that you will find for coated abrasives:

    • Cartridge rolls: 

    Cartridge rolls are abrasive coated rolls that are suitable for sanding and finishing spaces that are difficult to access. The cartridge rolls are used on inside surfaces and inside corners where other abrasives can not hit high-speed grinders. 

    Cartridge rolls have an aluminum oxide-coated material that can provide a versatile method of hand sanding, especially in metalwork.

    • Cross pads: 

    Cross pads are used for small channel polishing, end deburring, and workpiece finishing. The Cross Pads provide greater flexibility and make it easier for users to see through the contact region. 

    These cross pads are perfect for fast grinding on channels, corners, or spotting on flat surfaces.

    • Deburring Wheels: 

    Deburring wheels are used to wash, blend, deburring, finish, and polish metals and glass. For light to heavy precision mixing, deburring, and washing, these deburring wheels are ideal. 

    Deburring wheels provide uniform finishing to components and quickly and easily deburr the workpiece than hand finishing.

    • Flap Discs: 

    With a product that can grind and finish in one single action, Flap Discs offer precise angle grinding flexibility. It is ideal for most ferrous & non-ferrous materials for sanding and finishing of welds, deburring, rust reduction, and snagging.

    • Flap Wheels: 

    For most applications, from grinding to polishing, Flap Wheels are used. These flap wheels are usually used on ferrous alloy, high tensile materials, and a workpiece to finish complex shapes and tight contours. 

    The versatility of the wheel helps the wheels to navigate places that are hard to reach. On grinders, drills, impact wrenches, or handheld rotary tools, flap wheels connect.

    • Sanding Belts: 

    Sanding Belts are used for deburring, grinding, blending, finishing, and polishing. These belts are back with cloth, paper, or film.

    • Surface Conditioning: 

    Surface Conditioning Discs come in an all-inclusive range of grades and sizes and are an ideal first-step for washing, mixing, deburring, and finishing.

    Storage and Handling of Coated Abrasives

    Abrasives’ performance can be affected by improper storage of coated abrasives. Both types of backings are subject to temperature and humidity fluctuations during storage:

    • Keep the storage area at steady humidity (35-50 percent) and temperature (60-80 °F) levels.
    • Keep cartons away from damp or cold walls and floors where moisture can be absorbed.
    • Store coated abrasives away from any source of heat.
    • Fiber discs withdrawn from the original packaging should be placed in an appropriate disc holder and held under pressure.
    • On shelves or pallets, shop bulk rolls flat, not on the side.
    • Belts removed from the packing case should be rolled up and on a clean shelf standing on the edge. They can be drawn over a vast cylinder, but a belt can never be suspended from a nail or peg (the backing will crease, and the abrasive coat will crack)
    • It is preconditioning for optimum performance of the coated abrasive products in humidity and temperature-controlled setting before to use.