[tsomctl]

How about a plasma cutter? I know a plasma cutter will cut through normal silica. (I cut through some steel plate laying right on top of large gravel.) Silicon dioxides melting point is 1700 C, and aluminum oxide is 2100 C, a little higher.

[kbenson]

Isn't a plasma cutter actually melting an area out of a material and not actually cutting it?

[sk5t]

It does both!

[kbenson]

My point is that if you look at that definition of "cut", it's not just rendering one item into two pieces, other wise tearing or cracking something would be cutting it, and those aren't cutting either.

I doubt this material is impervious to shear force, or being lowered in temperature until it's brittle and cracked. But those aren't methods of cutting.

[catalogia]

I mean, this material is only resistant to drilling and grinding. Saying you "cut" something with an angle grinder is a fair use of the term, yet grinding away at something probably isn't the first thought people have when you just say "cut". I'd say the truest form of cutting is shearing, as with shears.

[Brian_K_White]

I don't see the distinction. Everything but shears removes material at the cut. A plasma cut is no different in that respect from a saw, grinder, water-jet, laser, torch.

[kbenson]

Cutting something with scissors, or in the case of thicker metal a press with a bit, doesn't remove material. Tearing something in two doesn't remove material. But you're right, any sawing type cut, as with a grinder, does remove material.

What I was really getting at though is that if you look at the definition of "cut" you'll see in most (all?) sources it defines it has being achieved through a sharp object or tool. I understand that's not often how it's used colloquially though.