Need formula for particular metal alloy, requirements inside

[Nutrient]

If you have a knife edge (dual sided at 45°, 1/8" thick, and you want as little deformation as possible under a 50 lb. load, what would be the ideal alloy?

Harden steel?
Tungsten?
High carbon steel?

Application: two point guitar tremolo, total tension being around 100 lbs.

Looking for low malleability, shatter resistance, high corrosion resistance to salt, and no oxidation to air.

Second point of contact, second type of alloy needed:

Looking for least friction possible, slightly higher malleability.

This is metal on metal contact, with no lubrication to help.

 

[Baluncore]

Tool steel would be a good choice because it is low cost and widely available in 1/8” thick rectangular sections.
Slightly more expensive, but with the least possible deflection would be carbide, as before, widely available in 1/8” section as tool stock. The manufacturers of carbide can provide knife edge sections or you can grind it yourself with a diamond dressing wheel. Avoid the dust as it contains cobalt.

There are many suppliers, here is just one example...
http://www.use-enco.com/1/1/87935-solid-carbide-rectangle-rectangular-carbide-blanks.html