Bonded Abrasives Vs Coated Abrasives
Although they are essential for many industrial and precision finishing applications, abrasive grains are not a one-size-fits-all material. They can be further separated by material type, grain size, use, and other factors. Coated and bonded abrasives, however, are the two most widely used platforms for abrasive applications. We shall examine these two uses of abrasive grains in further detail in this post.
BONDED ABRASIVES
In order to remove stock, grind materials, blend welds, cut, bevel, and sharpen materials, as well as provide precision finishes, bonded abrasives combine abrasive grain, filler, and bonding agents. The selectable grits range from ultra-fine to extremely coarse. Bonded abrasives are used in a variety of products, such as but not restricted to:
- Cones
- Mounted Points
- Chop saw blades
- Plugs
- Grinding discs
- Hand held grinders
- Cut-off wheels
HOW BONDED ABRASIVES ARE MADE
A variety of substances can be employed both alone and in conjunction with other bonding agents to help bond raw materials. The following bonding materials are most frequently used:
- Resin
- Rubber
- Adhesive
A variety of grains are offered for bonded abrasives. These consist of:
- CBN
- Silicon Carbide
- Diamonds
- Ceramics
- Aluminum Oxide
- Zirconia
- Combinations of grain materials
Specialty abrasive formulas are sometimes used to solve particular problems, such as grinding wheels for aluminum.
Grain is placed after glue has been applied to a backing sheet. The abrasive sheets are sliced into various sizes, shapes, and applications when the glue hardens. The new product helps finish a variety of workpieces in a number of applications.
FUNCTIONS OF BONDED ABRASIVES
Fast cuts, or soft bonding, rapidly erode the surface grains. Long-life connections, which are more challenging, have a longer lifespan. Contamination-free abrasives (including bonding free of contaminants) can be used in applications involving stainless steel.
The surface of a working substance gets worn down or removed while an abrasive works. This procedure keeps going until the workpiece is polished and shaped and the abrasives have removed the ideal quantity of material.
BONDED ABRASIVES: ADVANTAGES AND DISADVANTAGES
Bonded abrasives are engineered and designed to perform exceptionally effectively with particular tools. You may experience problems, like the bonded abrasive backing falling apart, if you attempt to use a bonded abrasive on tools designed for coated abrasives. Nonetheless, bonded abrasives have very few disadvantages when used as intended.
Regarding limits, bonded abrasives are typically not very successful at prep work, especially final prep work prior to a finish being applied, aside from equipment that is expressly intended for these types of abrasives.
Furthermore, a lot of bonded abrasive items are not shaped in a way that allows them to cover an object completely. Most bonded abrasive materials have a hard surface that prevents them from getting into objects with bends or dips. You can learn more about bonded abrasives by following the link.
COATED ABRASIVES
As the name suggests, coated abrasives are sealed in adhesive-secured abrasive particles by a top coating of resin. The process of adhering the abrasive to a product's backing is what gives coated abrasives their "coated" appearance. In particular, the resin serves as a protective layer that gives the final product protection, stability, and sturdiness.
Coated abrasives work well with a variety of products. The coated abrasives are supplied by the producer in large rolls for each variant. After that, the roll is sent through cutting equipment that creates abrasive goods for:
- Sanding belts
- Spiral Bands
- Cartridge rolls
- Drums
- Abrasive sheets (sandpaper).
- Quick change discs
- Flap discs
- Sanding discs
- Sanding rolls
- PSA sanding discs
To prevent heat damage to the abrasives, certain coatings, for instance, offer heat-resistant protection. Additionally, a unique coating that acts as an anti-static is applied in order to prevent the accumulation of stearate. It is only possible to manipulate the abrasives once each layer has dried.
HOW COATED ABRASIVES ARE MADE
Any flexible material capable of accepting adhesive can be used as a coated abrasive backing. Paper, film, vulcanized rubber, cotton, and polyester fabric are examples of this. Abrasive is applied to the backing, which serves as the basis.
On the backing, a base coat of adhesive—typically resin—is applied. An abrasive substance, or grain, is electrostatically added to the base coat after it has set but not cured. The abrasive is disseminated widely and evenly across the backing using the electrostatic approach, and the abrasive grain is oriented correctly.
The abrasives are attached to the backing when the glue has set, and then a resin layer is put on top of them. The abrasives are held in place, and the dried resin offers some wear and tear resistance.
COATED ABRASIVE GRAINS
Graining a coated adhesive is achieved by using multiple components. Although certain adhesives are suitable for many applications, most coated adhesives are designed for a particular use. Sometimes, specialty abrasives made to handle different kinds of work material are utilized as grains.
Frequently utilized grains include, but are not restricted to:
- Silicon carbide
- Aluminum Oxide
- Ceramic
- Zirconia
- Diamonds (used in specialized applications)
FUNCTIONS OF COATED ABRASIVES
There are many grit sizes for abrasives. Their grit size determines the abrasives' ideal function. For stock removal, for instance, greater grit grits (24 to 60) work best. For deburring, larger grit grits work best as well.
Applications such as surface preparation, mixing, and graining call for grits between 80 and 220. Ultra-fine grits, which come in sizes between 280 and 3000, are used as a pre-polish smoothing agent or on smooth surfaces.
COATED ABRASIVES: ADVANTAGES AND DISADVANTAGES
Coated abrasives have the same advantages as bonded abrasives in that they perform remarkably well when used as instructed. When utilizing one for basic tasks, even beginners can pick it up quickly. The same restrictions apply to coated abrasives as to bonded abrasives. Furthermore, the operator benefits instantly from specialty-coated abrasives.
For instance, a coated abrasive product will last longer if it has an additional coat to assist in preventing wear and tear. This results in material savings for the operator. The same holds for specific abrasives that stop the accumulation of stearate.
The primary disadvantage is that, although some are made specifically for that use, the majority of coated abrasives need help to do the soft task of non-woven abrasives. A workpiece that requires a precise finish is much more difficult because it needs that sensitive touch. Controlling the amount and depth of coated abrasives' penetration can be difficult because they tend to eat into their work. You can learn more about coated abrasives by following the link.
A COMPARISON BETWEEN BONDED AND COATED ABRASIVES
Compared to bonded abrasives, coated abrasives are manufactured using a different method. While bonded abrasives are made of abrasive grains kept together by a bonding agent, coated abrasives are made of a backing material covered with abrasive grains. Additionally, the range of applications for each abrasive varies. While bonded abrasives are more appropriate for precise grinding and cutting, coated abrasives are perfect for sanding, grinding, and polishing workpieces. Precision work benefits significantly from the more consistent finish that bonded abrasives offer in terms of performance. Coated abrasives, on the other hand, are more adaptable and suitable for use in small areas. Finally, bonded abrasives are more durable than coated abrasives, which are typically more economical.
CONCLUSION
To sum up, selecting the appropriate abrasives for your purpose is essential to getting the best outcomes. It's crucial to take into account elements, including the kind of material, the necessary surface finish, and the techniques and equipment being utilized.