Steel!
Ever wonder about the steel you use?
I've found that S-7(Sr-77) is a shock steel also known in the tool steel family.
SR-101 is 52100 modified. But HOW is it modified? Is it in the heat treatment or is something else added?
So we know that SR 77 and SR 101 started out as something else but what about INFI?
Where did this stuff come from? I know that early use in Busse Combat was done in tool steels, but was something added to the mix to make INFI? If so what???

From the fires of Mount Doom in the land or Mordor.

Here's a 2003 BladeForums post by Sal Glesser about H-1, which is Spyderco's nitrogenated steel where he mentions that X-15 and INFI include nitrogen. Also, here are a couple of pages that discuss the effects of elements added to knife steel:

Spydeco EDGE-U-CATION: Steel Element Information and
Swiss Army Knife Mall: Knife Steel.

There are no shortage of other references, and I'm sure that many are better. The main reason I included the Swiss Army Knife Mall page was that it stresses heat treatment as the #1 factor in blade performance, and that's where Bussekin knives excel. Now refer to Busse Combat's INFI information page. As noted at the bottom, INFI was not developed as a stainless steel, but it has strong corrosion resistance, probably in large part to the nitrogen. Though in the final analysis, INFI's legendary performance, along with that of SR101 and SR77, owe more to their heat treatment and quality control than to their steel formulation.

Awesome reply.

One knife to rule them all.

(Sorry, I had to do it.)

<img src="/ubbthreads/images/graemlins/laugh.gif" alt="" />

and in the sharpness bind them

my S5LE smells like bourbon

Well once you start looking at the "Riddle of Steel"....the truth is as strange as fiction....

The formula for Infi has been known for some time...it has been posted here often...it is close to other steels but not the same .... L8 is close .... L8 is used by Shiva Ki in knives which have a good reputation for their cutting ability and edge holding ... in both Infi and L8 by Shiva Ki the skill of the heat treatment outweighs the chemical components of the steel.

Dozier does a great heat treatment of D2....Paul Bos does a great treatment of S30V and CPM3 and CPM154 ... Jerry Hossum and Randy Lee both use Bos and their knives perform excellently ...

Shiva Ki has extensive Japanese Martial Art knowledge which includes steel forging...other Japanese masters of forging and heat treatment are Ichiro Hattori and his Cowry X damascus knives which are done by himself and Hiro Itou who does his own R2 damascus blades...these masters use damascus akin to the manner of a Japanese Sword...they sandwich the steel in layers of softer steel to give it greater strength and impact ability yet have the harder edge holding steel to give the blade it's cutting performance...

I have used them all except Shiva Ki ... once the heat treatment is accounted for in performance then for me it is the grind of the blade and specifically the edge...a convex appleseed "hamaguri ba" convex edge can come in different geometry features of thickness... Itou is thinner than Hattori... and this plays a part on performance as well in terms of cutting ability and durability of the edge...the best I have tried is Hattori ... he is also the oldest in terms of experience...and comes from a family of long established sword makers...so probably is the best versed in knowledge... Itou is a first generation maker...

Another master of grinding edges is Kiku Matsuda...he works in OU31 steel and I have'nt got round to his knives but I will one day...

At the top end of knives like this though the prices are pretty steep and the performance differences are judged in "nuances" when used in a normal fashion...basically it is how well they cut and for how long...for me Hattori has been the best...but for ease of sharpening in the field and price to performance... Dan's S5LE takes the crown IMO. His knife is a great user for the money...compare under $200 to over $1000 to even $2500 for the top end knife by Hattori...and you can see why I think the S5LE is such a good knife.

I am looking now at some damascus steels forged by top Scandanavian makers but they have not got a heritage of centuries developing the best grinds and experimenting like the Japanese did...although their handle designs are incredibly advanced for cold weather use...most japanese knives never got beyond the "weapon" aspect of stingray skin and cord which gives great grip when bloodied...however the Hattori knives in Sambar Antler which can be smoothed down make very comfortable "user" grips.

I doubt on my budget I will find a better knife than my Hattori...you would need to look back in time for Tanto's made from 13th Century Japanese swords which had had deep spine gouges taken out of them in battle and were re-cut to make Tanto blades...around that time the best Japanese swords were made... strange really that they peaked so early...but that is what chemical analysis has shown. The steel structure of these swords is reputed to have been used by Hitatchi and Diado when making the modern super steels...

The structure of the 13th Century blades was determined by the forging and folding process....and the quality of the minerals available...a bit like Wootz Damascus.... sometimes the quality of natural minerals was just tapped into at a given time and they found the best...only to be equalled in modern times when steel can be reduced to a powdered man made form.

The best Japanese Swordsmith for technical brilliance in his blades is widely accepted to be Masamune who worked in the Sagami province around 1288 AD.

If you look at the expense of Cold Steels San Mai range of knives...these were actually the cheapest of blades back then. An "Ori San Mai" blade had a bar of iron for the spine with an edge strip of steel welded between two bars of iron. For a "Shihozume" blade two plates were made from doubling and welding kataha bars 10 to 15 times. A thin bar of hard steel for the edge and iron for the back was then sandwiched between the laminated plates.

The best blades were made from laminated bars without a hardened steel strip inserted for the edge.Usually a kataha bar was folded and hammered 15 times,making a blade with over 32,000 layers.

Manasume would take four 32,000 layer bars, pile and weld, then fold and weld five times. These blades would be almost homogenous, with over four MILLION layers of Iron and Steel in less than one quarter of an inch of thickness!

This was only proven in the late 1970's when a Japanese bladesmith cut open a $60,000.00 Masamune blade ( now well over $200,000 ) and sent it off for special analysis. After this was done a whole new genre of super steels started to come out of Japan using powdered technology. Only in the 20thCentury did we finally catch up and understand the skills of the 13th Century...and even then it is only by reducing the steel to a component powdered form that they can approach the homogenous grain structure achieved with natural materials and forging skills back then.

It is always interesting to me that the very best steel in the world was made so long ago... <img src="/ubbthreads/images/graemlins/cool.gif" alt="" /> <img src="/ubbthreads/images/graemlins/thumbup.gif" alt="" />

Wow. That was unexpected. Great post Steelfan! Makes me want to learn more.

The very best blades seem to come about when a knife maker gets obsessed with perfecting their favorite steel to work with.
A good example mentioned earlier was the Onion D2. He has worked a basic tool steel into a virtual super steel. Before his stuff, I wouldn't have trusted a D2 blade that was much longer than 4.5 inches but I would trust him to make a machete out of it.
It is all about the heat treat.
Just like McDonalds and their chicken nuggets. Tough as a golf ball yet made from what was previously liquified chicken parts.

good answers! thanks guys!