: > Can someone point me to a web page or other resource that explains the
: > characteristics of the various steels used in knives? I have found
: several
: > web pages that describe steels that are available for folks who are making
: > knives, but none that cover all or most of the steels used in factory
: > knives. Specifically, I have not been able to find anything in 420 or
: 18/8,
: > both I have seen used in commercial knives.
: > Thanks, Gary
I'll be updating this soon.
rec.knives Steel FAQ
Author: Joe Talmadge j...@cup.hp.com
Last Updated: September 1999
Let me start with my bibliography. I got the knowledge for this FAQ
from my own experience as a collector and amateur knifemaker, and from
countless conversations with custom makers. I've also read countless
articles on steels, but here are the ones that I actually had in front
of me:
Bob Engnath's Blades and Stuff Catalog. Bob's catalog is a
must-see for everyone, even for just collectors, as it contains
a wealth of information on all kinds of great knife subjects.
There is a section on knife steels. Bob passed away in 1998,
but if you can find an old copy of his catalog, grab it.
"The Secrets of Steel," by Butch Winter, _Tactical
Knives_, Spring 1995.
"What Alloys Do For Blade Steel," by Wayne Goddard, _Blade_,
June 1994.
Email conversation with Wayne Goddard, February 1998.
Don Fogg's article on damascus steels from his website
www.dfoggknives.com (information used by permission)
"Inside Steel: What the Alloying Elements Do For Your
Blade", by Ed Severson with Steve Shackleford, _Blade, August 1999.
Also worth reading:
# A great steel comparison page
http://www.shreve.net/~primos/steelcmp.htm
# Principal Metals vast database of steel properties & terms
http://www.principalmetals.com
# Crucible's Steel Pages, loaded with info on composition/selection/etc.
http://www.crucibleservice.com/cscd/crumain2.htm
# Suppliers Online huge database of steel info
http://www.suppliersonline.com
#A.G. Russell's FAQ Pages
http://agrussell.com/faq/index.html
#Spyderco's Steel Page
http://www.spyderco.com/spyderco_products.cfm#steelchart
# Malex's Steel Data Chart for Knifemaking
http://www.online.ru/people/malex/
# Knives.com entire site is interesting, but hit "Tech", then "Steel"
http://www.knives.com
# Metal Mart's dictionary of metallurgical terms
http://www.metal-mart.com/dictlist.htm
# Kevin Wilkins small Steel Crossreference Chart (US/Germany/Japan)
http://www.wilkins-knives.com
# A list of metallurgical sites, schools, organizations, and journals
http://www.mlc.lib.mi.us/~stewarca/metallurgy.html
# Titanium Info
http://www.halperntitanium.com/
# Don Fogg's excellent info pages
www.dfoggknives.com
# A good steel chart
http://www.pizzini.at/steellist.htm
The State of Knife Steels Today (editorial):
There are some very interesting things going on in the knifemaking
world, steel-wise. In the non-stainless steel world, Benchmade's
offering of an AFCK with M-2 steel has set off a flurry of interest in
non-stainless steel, a very good trend in my opinion. EDI and Mission
Knives have both come out with A-2 folders, and Kabar with a line of
D-2 folders.
Stainless-wise, there are even more exciting things going on. ATS-34
has been on fire for the past 10 years or so, but the leading-edge
consumers and makers are already looking past it. BG-42 and VG-10 are
offering significant improvements over ATS-34 in edge-holding, and
improvement in toughness too. 440V and 420V leapfrog even those steels in
terms of edge-holding, with 420V having good toughness.
In the area of non-steel materials, the interesting titanium alloys
that came out a few years ago are joined by some promising ceramic
materials and cobalt alloys. Talonite offers the non-paralleled
(outside of ceramics) edge-holding and non-corrosiveness of the older
Stellite 6K cobalt alloy, but talonite is much cheaper and easier to
work, making it affordable enough to be an interesting material. Rob
Simonich, T.H. Rinaldi, and Kit Carson have been using talonite
recently. David Boye's BDC cobalt alloy, made with Boye's dendritic
process, is also promising. On the ceramic side, Kevin McClung's
ceramic composite shows that ceramics are available that are tough
enough to chop with (though still less tough than steel). This
ceramic holds an edge forever and is non-corrosive.
A well-informed, leading-edge knife buyer or maker should be looking
at these promising trends carefully. The use of new stainless steels
and cobalt alloys and ceramics, and the renewed interest in
high-performing non-stainless steels, are all very positive and
exciting trends in cutlery technology.
Introduction:
One thing to keep in mind is that there's more to knife performance
than the steel. The blade profile is also important (a tanto format
isn't the best choice to skin a deer, for example). But perhaps most
important is the heat treatment. A good solid heat treatment on a
lesser steel will often result in a blade that outperforms a better
steel with inferior heat treatment. Bad heat treatment can cause a
stainless steel to lose some of its stainless properties, or cause a
tough steel to become brittle, etc. Unfortunately, of the three most
important properties (blade profile, steel type, heat treatment), heat
treatment is the one that is impossible to assess by eye, and as a
result excessive attention is sometimes paid to the other two.
Remember also to keep your particular application in mind. 440A is
often scoffed at, but I'd rather have my salt water dive knife made of
440A than L-6. Properly heat treated 5160 is wonderfully tough, but
if my application is skinning deer, I'm probably more interested in
edge holding ala 52100. And on and on.
Steel Alloys:
At its most simple, steel is iron with carbon in it. Other alloys are
added to make the steel perform differently. Here are the important
steel alloys in alphabetical order, and some sample steels that
contain those alloys:
Carbon: Present in all steels, it is the most important hardening
element. Also increases the strength of the steel. We
usually want knife-grade steel to have >.5% carbon, which
makes it "high-carbon" steel.
Chromium: Added for wear resistance, hardenability, and (most
importantly) for corrosion resistance. A steel with at least
13% chromium is typically deemed "stainless" steel, though
another definition says the steel must have at least 11.5%
*free* chromium (as opposed to being tied up in carbides) to
be considered "stainless". Despite the name, all steel can
rust if not maintained properly.
Manganese: An important element, manganese aids the grain structure,
and contributes to hardenability. Also strength &
wear resistance. Improves the steel (e.g., deoxidizes) during
the steel's manufacturing (hot working and rolling). Present
in most cutlery steel except for A-2, L-6, and CPM 420V.
Molybdenum: A carbide former, prevents brittleness & maintains
the steel's strength at high temperatures. Present in
many steels, and air-hardening steels (e.g., A-2, ATS-34)
always have 1% or more molybdenum -- molybdenum is what gives
those steels the ability to harden in air.
Nickel: Used for hardenability, and toughness. Present in
L-6 and AUS-6 and AUS-8. Nickel is widely believed to
play a role in corrosion resistance as well, but this
is probably incorrect.
Phosphorus: Present in small amounts in most steels, phosphorus is
a essentially a contaminent which reduces toughness.
Silicon: Contributes to strength. Like manganese, it makes the steel
more sound while it's being manufactured.
Sulfur: Typically not desireable in cutlery steel, sulfur increases
machinability but decreases toughness.
Tungsten: A carbide former, it increases wear resistance. When
combined properly with chromium or molybdenum, tungsten will
make the steel to be a high-speed steel. The high-speed steel
M-2 has a high amount of tungsten. The strongest carbide
former behind vanadium.
Vanadium: Contributes to wear resistance and hardenability. A carbide
former that helps produce fine-grained steel. A number
of steels have vanadium, but M-2, Vascowear, and CPM T440V and
420V (in order of increasing amounts) have high amounts of
vanadium. BG-42's biggest difference with ATS-34 is the
addition of vanadium. Vanadium also refines the grain
structure, resulting in a tougher steel.
CARBON and alloy steels (non-stainless steels):
These steels are the steels most often forged. Stainless steels can
be forged (guys like Sean McWilliams do forge stainless), but it is
very difficult. In addition, carbon steels can be differentially
tempered, to give a hard edge-holding edge and a tough springy back.
Stainless steels are not differentially tempered. Of course, carbon
steels will rust faster than stainless steels, to varying degrees.
Carbon steels are also often a little bit less of a crap shoot than
stainless steels -- I believe all the steels named below are fine
performers when heat treated properly.
In the AISI steel designation system, 10xx is carbon steel, any other
steels are alloy steels. For example, the 50xx series are chromium
steels.
In the SAE designation system, steels with letter designations (e.g.,
W-2, A-2) are tool steels.
There is an ASM classification system as well, but it isn't seen often
in the discussion of cutlery steels, so I'll ignore it for now.
Often, the last numbers in the name of a steel are fairly close to the
steel's carbon content. So 1095 is ~.95% carbon. 52100 is ~1.0%
carbon. 5160 is ~.60% carbon.
O-1
This is a steel very popular with forgers, as it has the reputation
for being "forgiving". It is an excellent steel, that takes and holds
an edge superbly, and is very tough. It rusts easily, however.
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