While it’s true both tools are abrasive, diamond grinders and abrasive grinders use different material builds. True, both equipment types utilize fast-spinning discs, so that abrasive strength is available as soon as the rotating disc surface gets up to speed. Looking deeper, though, right at the blade grain, the physical differences become clear. Unlike a diamond blade’s steel core and sinter-bonded crystals, abrasive grinders rely on scratchy metal oxides.
A Different Bonding Structure
Let’s depower an abrasive grinder and make it safe. By holding it up to the light, it’s clear the tool uses a different physical build. The blade is rough and made of a resinous substance, which has been bonded to a metal disc. The abrasive particles are married to the bonding material, so they spread uniformly throughout the resin. And that resin isn’t necessarily the only bonding agent used here, not by a long shot. There are vitrified clays, which melt like glass. Special rubbers and mesh layers also find their way into the mix.
Silicon Carbide Abrasiveness
The biggest difference is seen in the abrasive particles locked inside the bonding disc. There’s not a single diamond to be found inside a conventional abrasive blade. No, this is a mass of evenly interspersed aluminium oxide particles. And this family features an extensive range of gritty substitutes, among which zirconia alumina and ceramic aluminium oxide rank highly as steel alloy grinding materials. Silicon carbide is another member of the abrasive grinding family, but this material does add a major hurdle to a tool operator’s workflow.
Revisiting the Diamond Differences
Up there with cubic boron nitride (CBN) blades, nothing known to man can cut as effectively. Diamonds are also sintered to steel cores, which won’t wear or break, not like a vitrified blade. Take note, though, some “welded” steel diamond blades have been known to fracture and break. However, generally speaking, those glassy/resin-like abrasive discs do wear out faster, and they do incur more damage. Worse yet, aluminium oxide grit produces a long stream of sparks, so it adds a fire risk to the work. Ultimately, and maybe most importantly, abrasive discs can kick out silicon carbide fibres. Let’s be candid, for lives are on the line, those fibres can have serious long-term effects on an operator’s health, so always wear breathing apparatus when using this tool type.
The name of that ailment is pneumoconiosis. Long-term exposure to silicon carbide does cause lung damage. There’s even some evidence that suggests a lung cancer connection. Apart from such health risks, aluminium oxides and vitrified bonding agents wear faster than steel cores and their sintered diamonds. Diamond blades are generally safer to use, they’re more fatigue resistant, and they can cut the hardest, most challenging materials.
