No matter if it is used for grinding off rust off metal or prepping for welding, an abrasive wheel is sure to make the task go more efficiently. When selecting your wheel it is important to consider factors like grain size, grit and bond type.
Abrasive wheels are constructed using powdered abrasive grains held together by resin or aluminum oxide glue binders, with sharp abrasive grains cutting into surfaces as they pass over them.
Types
Arguably the most essential material in any application, abrasives are indispensable. Each application calls for different kinds of abrasives; metal grinding wheels require aluminum oxide abrasives which are capable of sanding high tensile materials like steel and high tensile bronze alloys; while for other purposes softer materials like silicon carbide may be more suitable.
The type of abrasive you choose determines its cutting capacity, processing adaptability and required grit size when grinding or cutting material. Furthermore, physical and chemical properties of workpiece materials must also be taken into consideration before selecting an abrasive type.
Aluminum oxide and silicon carbide are among the most frequently used abrasives, with silicon carbide often coming in two varieties – black and green. Black silicon carbide boasts higher hardness and brittleness than corundum artificial abrasives, making it suitable for grinding cast irons, nonferrous metals with low tensile strength as well as harder metals and nonmetals with higher tensile strengths such as die-fine grinding or engine cylinder honing applications. Green silicon carbide has more friability than its black counterpart, making it suitable for processing harder metals or nonmetals with higher tensile strengths such as die-fine grinding or engine cylinder hone. Abrasive grains mixed with bonding agents then pressed into wheels which then get heated in an oven or similar device which vitrifies their bond and holds together securely all at once.
Anvendelser
Silicon carbide abrasive wheels can be used to grind materials such as aluminum, cast iron and non-ferrous metals as well as ceramics and stone. Furthermore, these wheels make an excellent solution for soft materials like wood and paint as they produce minimal heat output while producing high quality finishes with minimal waste produced.
Grit of an abrasive is an integral factor when selecting a wheel. Grits range from coarse to fine; higher numbers indicate finer grains. Furthermore, depending on what material is being ground (such as aluminum oxide or zirconia alumina grains which work better on metals with higher tensile strengths vs green silicon carbide grains which work on harder or brittle materials), some wheels require different kinds of abrasives than others.
Unitized wheels differ from other forms of bonded abrasives in that they combine non-woven fiber strands and an abrasive mineral with a tough resin bond to form an extremely durable wheel, capable of withstanding heavy pressure. Available in various densities – from soft 2 density for conformability applications up to hard 8 density for increased edge durability – unitized wheels offer unparalleled durability when it comes to resisting wear and tear.
Grit
Grit size on a grinding wheel label indicates how fine or coarse its grains are; larger grit sizes take larger chips out of metal surfaces with greater force, leaving rough surfaces behind, while smaller grit sizes produce smoother finishes at faster rates with reduced force consumption. A hard grade bond works best on harder materials like carbide or hard tool steels that withstand higher temperatures; soft grade bonds erode slower to expose new grains that work well on softer metals such as aluminum bronze or iron.
Aluminum oxide is the go-to abrasive for metal wheels, as it works on various materials and metals. If you require longer lasting rough cutting abrasives for carbon and alloy steels as well as hard metals like copper and titanium, zirconia alumina could be worth considering as it withstands higher temperatures than aluminum oxide while self-sharpening itself over time.
Bonds
Bond and abrasive material selection determines a wheel’s performance. For maximum cutting results, its grains must be hard enough to cut through workpiece materials while its bond must hold together during cutting operations. Different bonds and abrasive materials have unique characteristics designed to meet specific applications.
Aluminium oxide wheels are often recommended for grinding soft metals and cast iron, while zirconia alumina excels at grinding steels and alloys. Diamond or cubic boron nitride (CBN) wheels may also be utilized when working on extremely hard materials or high strength steel alloys.
Abrasive grains and the bonding material are mixed in a bowl before being blended, then compressed and sintered into wheels with an abrasive surface for cutting the workpiece, as well as an indication of how densely packed together they are. Wheels with higher structure numbers tend to produce faster cutting rates; ones with lower structures numbers require more power/amps for driving them and result in poorer finishes. A vitrified bond holds together these grains and provides consistent cut rates by continuously exposing new particles as older ones wear away over time.
Unitized Wheels
Silicon carbide comes in various formulations to meet the demands of various applications. Blends combining silicon carbide and aluminum oxide allow metal grinding with extended lifespan on soft alloys.
Vitrified bonds, similar to glass, offer rigid and strong grinding solutions that are resistant to high temperatures and grinding pressures without reacting with water, acids or oils.
Unitized wheels are perfect for metal deburring and cleaning, featuring several layers of non-woven abrasive material impregnated with resin that produces an exceptionally durable product, ideal for light material removal while imparting an attractive finish without altering workpiece shape.
These non-woven wheels are specially designed for general metal cleaning, deburring, and polishing applications. Ideal for use on various metals to remove rust, discoloration from welds and minor pits or scratches as well as coatings overspray from resins and adhesives overspray. Run smoothly on multiple machines while being easy to maintain; great for finishing preparation!