Is there a type of hardened steel that is resistant to grinding?

[Yorpheus]

I want to use a length of steel as a straight edge for working with Aluminum that is resistant to grinding with a Dremel and/or filing.

I was thinking D2 but wondered if anyone here had other suggestions.

 

[micdavis]

Yeah. All of it.

Of course it's resistant to grinding. That's why you have to grind it. And it throws all those pretty sparks when you do it.

Seriously if you are going steel against, aluminum the AL will naturally give way before the steel. It's a matter of pressure. Press hard enough to hit the AL but not so hard to grind the steel.

 

[Serafino]

When gunsmiths want a guide to file down to in final fitting something they sometimes use hardened carbon steel (probably more than file-hard).

Since you want to buy something that's ready to use, just find the material with the highest Rc rating in its current form. Something like an M-series High Speed Steel would probably be about as good as you can get for reasonable $.

 

[Sidewinder]

A standard stainless steel metal ruler should do as they are generally Martensitic Stainless which is a cutlery grade and have high hardness. The 'Rc' (sic) mentioned above is Rockwell Hardness 'C' (HRC) a type of test to determine hardness by a particular type of testing rig.

SAS

 

[Crimsonnaire]

One should bear caution when using Rockwell hardness to judge a material's wear resistance.

Rockwell scales measure plastic deformation, not to be confused with abrasion properties.

 

[Sidewinder]

The Rockwell test measures hardness, higher hardness = more abrasion resistance.

SAS

 

[Crimsonnaire]

There are different forms of hardness, each with corresponding scales.

For scratch/abrasion properties, you want to go by the Mohs scale. The Rockwell scale isn't one that measures wear resistance.

 

[acerocket]

You could try to find a tungsten flatbar. Or even better would be a carbide bar. There is a reason most metal cutting inserts (like those for CNC mills and lathes) are made from carbide. I had to cut down a 3/4" solid carbide boring bar once. Took about 2 hours to cut all the way through it with a diamond blade. Don't know if you could even find carbide flat bar, and if you did expect to pay $$$$$$.

 

[Sidewinder]

Hardness is hardness. There are different methods of testing it, that's all - Vickers Hardness is a better method (also uses an indenter).
Moh's scale is for minerals etc. not metals.

Wear resistance comes from the material's hardness.

SAS

There are different forms of hardness, each with corresponding scales.

For scratch/abrasion properties, you want to go by the Mohs scale. The Rockwell scale isn't one that measures wear resistance.