While looking in Machinery?s Handbook for the ?difference? between W1
and 1095 steels, I realized that the ?Letter Symbol? AISI/SAE
classification system for tool steels didn?t appear until its
nineteenth edition, 1971. So, if you want to look up W or O or H series
tool steels, you will have to have a 19th or later edition.
For those who are interested, this classification system doesn?t
appear to introduce any new steels, it just collected data on the ?tool
steel? usages of existing AISI and or SAE types.
----Oh--- what?s the difference between W1 and 1095? Nothing, maybe,
but W1?s carbon content can be as low as 0.6 % and still meet the
description of the class. Usually, though, W1 seems to be sold as
?Carbon = 0.95% - 1.05.? It has no significant alloying elements.
The difference is in the fine print. ;)
Both are AISI/SAE specifications and the steel's ability and/or
quality to match them.
The tool steel W1 is an electric furnace steel and maybe even
vaccuum-electric-arc re-melted. The cances of a vaccuum re-melt
increases with the higher alloyed steels like A2, D2 and M2.
Copper content on 1095 is .60% maximum and silicon content is the
same .60%Si-max, even tho you won't see it listed either.
Maximum copper content on all tool steels except the W series is
.25% and .20%Cu-max on the W series. In practice it's much lower!
Stainless steel is understood to have .35% to .65%Cu unless
otherwise stated (it oozes out into and protects the grain boundries
when the alloying is so high, especially when Cr is present).
HSLA (high strength low alloy) steels are strengthened by copper's
solid solution with iron which is alot like nickel that way. But
for me, as a knife-knut, copper is an impurity.
I don't know the business-end or politics of these designations...
I had some 50100-B spectrographed and it would easiy fit inside the
specifications for W7 tool steel. (composition-wise) But they don't
call it "W7 tool steel"...
Is it because the steel would have to be submitted to AISI and/or
SAE to be approved? If so, what would that cost? What might they
be doing or not doing in the production of the 50100-B that would
disqualify them, and would that cost more money to correct? What
would it gain them to call it W7 anyway?
"Carbon and Alloy Steels" are listed in one section and the "Tool
Steels" are listed in another section for lots of reasons. ;)
"Carbon and Alloy Steels" are used for "machine parts".
If you want to get the best steel to be had to cut something, look
in the "Tool Steel" section. ;)
Alvin in AZ