Here is a Latrobe example, the ability to withstand abuse ranks S7 as good, H13 as exceptional, and D7 as poor, however the strength side the roles are reversed, with S7 being the median.


ASTM Grade Name Description Toughness
Wear Resistance

D7 LSS™ D7 An air-hardening tool steel 3
with maximum wear resistance for an ingot cast steel. Large, 6
hard carbides resist wear

S7 LSS™ S7 An air hardening, shock resistant 7
tool steel with better dimensional stability in heat 3
treatment.

H13 LSS™ H13 A 5% chromium hot work steel which 10
is often used in cold work tooling applications which need 2
high toughness but not high strength.

another comparison
[Linked Image from i540.photobucket.com]

in this example 3V is the winner for overall use here, while S7 has the ability to take repeated poundings..(lets use a press for example)...the strength isn't great enough to keep going, A2 would wear out shortly after, followed by D2, but replacing S7 with either the D or A2 steels means your more prone to breaking, so 3V offers the alternative, a little easier to understand might be , I have an equal razor edge on both SR77 and SR101,
both with exceptional heat treatments,

I might be able to whack the 77 a few more times with a sledge hammer on the spine,but its edge will fail(or roll) long before the 101,

I can resharpen them both, but once again the 77 does not have the strength to hold its edge compared to the SR101...does that help?


JYD #98