Separating fact from fable, today’s post is on the lookout for diamond cutting specifics. How do diamond coated tools work? Sure, we’ve identified the blade types. They’re segmented, continuously formed or fitted with turbo-rimmed edges. That’s all well and good, but it doesn’t answer the big question. How do they work? Strangely enough, to be absolutely honest, they don’t cut. Diamond coated blades grind.
Exposed Diamonds Grind
Caught in a metal matrix, a form made possible by special metal bonding techniques, sinter-mounted crystals are exposed. As the grinding disc gets up to speed, the abrasive particles grind their way through a given material. The scratching effect gains momentum, and the tool carves out a sharp-edged incision, which goes deeper and deeper.
Possesses Self-Sharpening Features
As the exposed diamonds wear and crack, the abrasive action forces them away. The old layer of diamonds is eroded out of existence, but they’re immediately replaced by a new layer, which was in a state of repose below the top layer. The process repeats. Every time a layer of diamonds wears away, the bonding agent and destroyed crystals erode, and a new layer is exposed.
Intelligently Selected P.C.D
PolyCrystalline Diamonds are industrial diamonds, not the multi-faceted variants that are found mounted on sparkling engagement rings. Formed from tiny particles, the fine crystals are compacted and bonded to a steel core. A special bonding agent completes the sintering process. The abrasive crystals are badly flawed. They’re never going to make it to a jewellery showroom. However, the crystals have a rated friability rating. They chip and fracture in a predictable manner.
Performance-Tuned Cutting Attributes
The polycrystalline particles are sized and graded. They’re coarsely or finely faced, and they’re friable. Bond hardness is the next variable of importance. A softer bond helps the broken crystals fall away. That’s a feature that’s desirable when grinding harder material substrates. Inversely, harder bonds cut through softer materials. Next, on returning to grain coarseness, the mesh size of the diamonds needs to be determined. High mesh numbers, in excess of 240, assure a smooth grind. Below 60, the grinding experience made possible by a diamond cutting tool is much coarser.
So there’s a list of facts acting as a grinding framework here. Perhaps they’re tidily printed on a datasheet. Sure, rim geometry is important. We want a continuous rim or a segmented cutting edge. Going deeper than rim shapes, though, there are the characteristics of the sintered/bonded polycrystalline diamonds to establish. They need to be fine or coarse, as determined by a mesh number. The bond hardness enters the selection mix, too, as does the friability of the grinding edges.