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Titanium/Teflon plating high speed steel

 

Alright, my interest is blades. I'm partial to high speed steel. I have seen sites that sell high speed steel drill bits with titanium coating, advertising a rockwell of 102. Now, I'm not hoping to achieve this, but I'm wondering if there's a way to plate the high speed steel knife blades I make with titanium ( 6-6-2 or better preferably though I understand that might not be possible) and ...( I know this is getting long) possible even place a Teflon coat on over the titanium ?

I have access to fairly complete shop. Would be deeply grateful for info on this.

Thanks,

Matthew Shorey
- Cumberland, Maine, USA

Hello Matthew!

The high speed drill bits are actually coated with Titanium Nitride, not titanium. You CAN sputter coat with titanium, but it is usually a stupid idea because it can give you a soft, easily galled layer without corrosion resistance, a bozo combination. I've only used it to satisfy some specsmanship issues on spacecraft applications.

You can certainly get the blades TiN coated, or CrN coated to provide a bit more corrosion resistance, or ZrN coated, to make it look golden, or combinations of those. These are all Physical Vapor Deposition (PVD) processes, done in a vacuum chamber. Richter Precision have done a fine job for me: give them a call, and they'll tell you all about what PVD can, and can't, do.

The Rockwell C reading of 102 is bogus, however; they've taken a microhardness reading of the coating and invalidly converted it to a Rockwell C, by incorrectly assuming a linear correlation. It ain't so. It is hard, harder than the Rockwell C scale goes, but still. . .

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York