Selecting an abrasive wheel depends on both the material being ground down and its grinding process, so understanding their interaction will enable you to select an optimal abrasive for your job.
Aluminum oxide abrasive is an ideal choice for rough sanding materials with low tensile strengths such as stainless steel, bronze and aluminum alloys. Furthermore, you can combine this abrasive with green silicon carbide for soft metal grinding applications.
Sharpness
A silicon carbide abrasive wheel’s sharpness is determined by its grain size and type. These grains cut through material being ground into chips that break off more efficiently over time; but over time their cutting points wear down and become blunt, leading to less efficient cutting as less of the grains penetrate material easily and friction builds up heat that fractures or disintegrates bond bridges holding them together.
Alumina (al2O3) and silica sand are two popular abrasives used in grinding wheels, with aluminum oxide being best suited to materials with higher tensile strengths and silicon carbide more suited for nonmetallic materials with lower tensile strengths like glass or ceramic. Silicon carbide also offers finer abrasive action than aluminum oxide making it suitable for applications requiring precision surface finishes like aerospace workpieces.
Σκληρότητα
Hardness of an abrasive determines its ability to cut materials. Silicon carbide wheels come equipped with grains ranging from brown corundum (A grade) to green silicon carbide (GC grade). A harder grain works best on tougher materials while softer grains work better with soft metals.
Abrasive grains come in various sizes that determine their roughness. Aluminum oxide (A grade) works well with steel and iron while zirconia alumina grains tend to be more durable for use on non-ferrous metals with lower tensile strengths.
Black silicon carbide features higher hardness and brittleness than white corundum, making it the ideal material for grinding gray cast iron, brass and aluminum. Additionally, its processing glass, stone, refractory materials as well as cemented carbide and other hard alloy grinding makes this type of silicon carbide less suitable for wet sanding applications; green silicon carbide offers harder yet purer cutting action at increased brittleness than regular black silicon carbide.
Ανθεκτικότητα
Silicon carbide abrasive wheels have proven essential in many applications that demand rigorous finishing work, particularly those involving hard metals, ceramics and fused quartz without damaging their substrate or introducing contaminants into the finished product. Furthermore, this material boasts low impurity levels for accurate cutting performance as well as good thermal conductivity and an impressive melting point.
Different abrasives are available depending on the material being ground; aluminum oxide works best when grinding ferrous materials and high-tensile metals, while zirconia alumina works better on cast irons and nonmetallic low-tensile metals such as non-ferrous alloys like cast iron. Silicon carbide works for nonferrous metals, stone and glass materials.
Standard Abrasives’ Quick Change Silicon Carbide 700 Series Unitized Wheels combine soft density, sharp-cutting silicon carbide mineral with a tough resin bond to form an affordable yet effective abrasive product that effectively smoothes, deburrs and finishes parts. Their conformability allows them to meet tight tolerances such as polishing jet blade fillet areas prior to coating process or soft metals such as soft metals for optimum results.
Safety
Safety should always be top of mind when operating any abrasive wheel. Hazards that could arise include particles ejected from either the wheel or workpiece, contact between wheel and work piece and trapped fingers in spindle, etc. All abrasive wheels should only be used on machinery equipped with appropriate guards and flanges and only at recommended speeds; operators of such wheels must receive training in understanding risks effectively managing them.
Each abrasive wheel consists of two primary elements – the cutting grains that perform cutting action, and their support via bond. Different grains and bonds provide distinct cutting characteristics: aluminum oxide is popularly used to grind metals such as iron; however, its cut rate and durability often fall short of other grains like silicon carbide which have sharper, harder and more rigid grains to easily cut glass, plastic and medium density fiberboard with ease.