Friction forging

[Raukodur]

Came across this, couldnt find any mention of it on these forums:

http://www.diamondbladeknives.com/frictionForging.aspx

And a review:

http://findarticles.com/p/articles/mi_m0BQY/is_8_54/ai_n27506035/

What do you guys think? Incredibly expensive blades, but if what they say is to be believed, than this seems to be the 21st century equivalent to a samurai sword, in a knife blade...

[Mike, Lord of the Spammers!]

I'll have to have a read of those when I'm a bit more awake mate

[J-sews]

Can't say as I'm familiar with that process Rauk. It sounds impressive, but then again we are bombarded with so many "superior" methods of making knives these days that I guess I've become generally skeptical.

Does anyone here have any first hand experience with these blades?

[Raukodur]

some of the info from the site for those too lazy to click 

This introduction to Friction Forging® will cover the technical aspects and terms of what makes a good blade and how we create a "Super Blade" through Friction Forging®. We will briefly discuss some time proven and tested methods that produce blades and edges that consistently out perform others. Our research has developed techniques and made technological advances that take manufactured knife-edge performance to the next level.

Friction Forging® does not involve a "mystery", or "secret steel". To the contrary, Friction Forging® involves metallurgical, chemical, and engineering facts gained from years of research performed at MegaDiamond, Advanced Metal Products, DiamondBlade, Knives of Alaska, universities and other companies. Performance advancements were built upon a metallurgical knowledge base from decades of research and practical knowledge in metallurgy, knife making, and general industrial uses of steel.


What is a Super Blade?

   1. STAYS SHARP LONGER: A blade that holds a "shaving sharp" edge significantly longer than any premium blade steels when comparing blades that have the same EXACT edge and overall profile geometry and when the other blade steels have been heat-treated, processed and sharpened to their maximum "best performance" characteristic.
   2. HAS FINEST GRAIN STRUCTURE: Measured with Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM) micrographs, Friction Forging® has been proven to create "nanosized" superfine grain structures. Finer grain structure equates to greater edge strength, toughness, and a longer lasting edge.
   3. DIFFERENTIALLY HARDENED BLADE: A knife that has a fine-grained, hard, tough edge for long-lasting sharpness yet the remainder of the blade is softer and slightly "springy" and very tough is one of the trademarks of a superior blade.
   4. CORROSION AND RUST RESISTANT EDGE: A blade edge is subject to chemical as well as abrasion deformation (dulling). A stainless edge reduces or eliminates this problem. Friction Forging® creates a super stainless edge by increasing the Chromium content in the ferrite.



Chemistry

A "Super Blade" steel must start with "the right stuff" in it before we attempt to make it better through Friction Forging®. Blade steel is mostly iron-ferrite. When controlled amounts of other elements, especially carbon, are added iron becomes steel. These added elements increase strength and toughness, machinability, and corrosion resistance and hardness for better edge retention. Vanadium (V), Chromium (Cr), Molybdenum (Mo), Carbon(C), Manganese (Mn), and other elements combine to bring desirable blade characteristics. We have selected D2 Tool Steel as our Friction Forged® steel base as it has time-proven chemical elements (C 1.5%, Cr 12%, Mo .8%, V .9%, Mn .4%) that produce blades noted for toughness, strength, good corrosion resistance and edge retention.



Forging, Heat Treating, and Grain Structure

What is forging? "Forging" is the technique of shaping steel, through pressure and heat by hammering, pressing, or rolling. Knife blades have been forged for thousands of years, using hand-held hammers, power hammer mills, or some other pressure exerting force. Steel exhibits polymorphism characteristics, that is, it can exist in different states from a fine-grained, super hard and brittle material, to one more ductile and coarse grained. When forging is performed in conjunction with the proper heat treatments termed thermocycling, the crystalline structures of steel, (grains), can be changed.

When blades are heated above the transformation temperature and held there for a period of time, the grain structures become finer, alloyed and chemically homogeneous with the desired elements. At these high temperatures, when the blade steel grain structures are transformed to a very fine state, it is referred to as austenite. The quench is a technique of cooling the blade in still air, circulated air, oil or other quenchant. When cooled slowly the grain structures will change to a softer, larger grain sized mixture termed pearlite and cementite, and the steel will be softer. If quenched from the transformation temperature quickly (less than 10 seconds), and under controlled temperature/time schedules, the pearlite transformation is "frozen" out, and the austenite becomes fine-grained, hard martensite. Friction Forging® provides rapid heating, deformation, grain refinement through dynamic crystal shearing, and rapid cooling to produce an outstanding microstructure. Gas nozzles create an argon gas "hood" over the processed zone to reduce oxidation and further assist the quenching process.

Visualize a steel blade as an object made up of a multitude of crystalline, multiple faced structures with distinct boundary regions between the different grains. It is accepted common knowledge and a metallurgical fact that the finer the grain, the stronger the metal. In other words, the steel is not as prone to develop cracks and chips in a mosaic of fine-grained as opposed to coarser grained material. This is especially the case when there are no "buffers", such as oxides between the grains that will be prone to allowing a crack to run between the grains in the oxide regions. In addition, the knife-edge is less prone to deform (dull) when that edge has a hard and fine-grain structure. Thus, the finest knives in the world will have a fine-grained and hard, but not brittle, edge and they stay sharp longer-much longer!
Differential Hardening and Tempering

Blades that are uniformly hard throughout are more brittle and will break rather than flex when significant transverse loads are exerted. Extreme examples are flint, ceramic and glass. If sharpened, all would have extremely sharp, hard edges but will not stand much transverse force. The same holds true for a steel blade. If it is uniformly hard, the blade is not very forgiving and will break more easily than a blade with a softer spine but hard edge. Thus another measure of a high performance blade is one that has a softer tough spine and a very hard edge that is not so brittle as to chip in normal use. Processes to obtain this characteristic are termed differential hardening. When done by a master blade smith, the edge is heated to the critical transformation temperature then quenched quickly, between 1 and 10 seconds for maximum hardness and then tempered. Tempering reduces brittleness from the pure martensite grain structures by relieving stresses developed in the rapid quench. Tempering for standard knife blades is accomplished by re-heating to a few hundred degrees for a specified time and that produces slightly softer steel to reduce brittleness but the trade off is that the edge holding ability is reduced.

Historically, the very best blades have the fine-grained, hard, superior edge holding characteristic that, through tempering, has removed the "brittleness" from the edge. The remainder of a high performance blade will be tempered differentially to obtain the softer, tougher steel that is resistant to breaking and will have a certain "spring" to it.
What is Friction Forging® a Knife Blade?

"Friction" Forging® is a localized forging process achieving high, transformation temperatures and high loads against a blade and then employing specialized techniques to achieve a rapid quench. The Friction Forging® is performed on the knife blade in the area that will eventually become the edge. Friction Forging® uses a specially designed tool made from Polycrystalline Cubic Boron Nitride (PCBN), a material second only to diamond in hardness. During forging, the PCBN tool penetrates the blade while rotating, which creates frictional heating. When the tool is fully engaged, it moves along the eventual blade edge, creating dynamic microstructure shearing and the high forging pressures that produce excellent blade microstructures. The speeds, heat and down forces are monitored and controlled by the process computer to ensure the creation of a high-quality blade.

The blade edge is brought up to the transformation temperature by the tool. As the tool moves, the blade material is continuously forged. The combination of thousands of pounds of forging force, tool rotation, and temperatures above the transformation temperature produces dramatic reductions in grain size. The grains are in effect torn apart and reduced in size by the combination of very high pressure and heat. Transmission Electron Micrographs indicate that the grain size is reduced due to Friction Forging from 5 microns in typical heat-treated D2 steel down to 0.5 microns, a superfine "nanograin" size. As the steel is brought up to transformation temperatures while Friction Forging®, the carbides dissolve and go into solution. Because the quench occurs so rapidly, some of the Chromium does not have enough time to reform as a Chromium carbide and is "frozen out" in the ferrite and a stainless zone is created where the Friction Forging® has occurred. This zone is so corrosion resistant that a 10% nitric acid etchant will not etch the processed zone.

The primary benefit of rapid cooling (quenching) is that the higher HRc values are obtained (65 to 68); yet because the grain size is so small and thus tougher and stronger, the brittleness normally observed in steel taken to these high HRc values does not occur. The higher the HRc values, the better the cutting performance and edge longevity-as long as the brittleness issue is managed as it is with Friction Forging®.

As Bob said, would be useful if we had some info from a first hand user...or anyone here tempted to spend $495 based on the info here?

one below looks particularly nice:

[Magnus]

well, reading through the horrible pseudo-science with with far too many ®'s.  It seems that someone has automated differential hardening, that is all.

[Raukodur]

From what I understand they have automated the same technique used by e.g. the Japanese to create samurai swords. And by automating it, they have been able to refine and improve it.

If this is the case, and what they say isnt all hype, than I can kind of understand the very high price.

One of the questions I have is what advantage does this blade have over other blades in everyday use, except staying sharp for longer (if it has that advantage like they claim). The thought comes to mind that the characteristics of a samurai sword or damascus sword are advantageous because of the very harsh conditions those items are used in, e.g. slicing through bone as you try and chop off someones head or limb, or clashing with another sword edge. Where on earth is a folding knife going to be used in such a setting, or its equivalent?

[yud]

I am reminded of a Canadian car show after the new car reviwe the guy would say "do you need a car like this? No. Do you want a car like this? Oh yeah."

Well do you need a steel like this? No. Do you want a steel like this? Oh yeah (I don't I am fine with SAK steel).

so I would say this from what I read on here in more the steel to show off to your frends

[Freudian Frog]

Ugh, at that price point I just don't care what they've done to it. =|

[Magnus]

From what I understand they have automated the same technique used by e.g. the Japanese to create samurai swords. And by automating it, they have been able to refine and improve it.

If this is the case, and what they say isnt all hype, than I can kind of understand the very high price.

couldn't you buy a hand-forged differentially hardened knife for about that?

[Raukodur]

I think they aren't marketing this the right way.

What they need is a series of videos of this knife being compared to other high end, expensive knives currently on the market for a whole range of extreme applications, and then SHOW the results in terms of damage to the knife blades, or decreased sharpness as a result.

They should finish with a video of two martial artists going at each other, one using this, and the other using the other knives, just for fun, to see how they compare in direct combat and contact.

Watching all of that would give all that they say about how awesome these blades are more credence.

[Raukodur]

Ok, so this article has some reviews by respected people who use knives daily, and know what they are talking about after having used the friction forged knives in real everyday conditions:

http://www.chuckhawks.com/diamondblade.htm

Hmm one thing to note, the prices mentioned at the bottom of that article are a LOT lower than the those mentioned on the current diamondknives website.

[Splat]

There's been a lot of debate about this particular way of making a knife being "forging". From what I've read it's creates a pretty impressive blade that holds an edge rivaling the top tool steels, such as M4 or D2. For my money I'd go with D2.

[Raukodur]

There's been a lot of debate about this particular way of making a knife being "forging". From what I've read it's creates a pretty impressive blade that holds an edge rivaling the top tool steels, such as M4 or D2. For my money I'd go with D2.

  it starts with D2...?

I was wrong about the pricing, there is actually a range from $295:

http://www.diamondbladeknives.com/productList.aspx

To $495.

Still exorbitantly expensive.

[Magnus]

I am going to have to stick with my assertion that it sounds quite dubious and pseudo-scientific until I see a proper explanation of how they are made, or better yet, a video.

I also did a patent search for the company behind this and could find nothing that relates to knives despite their assertion that the process is patented.

sorry to sound so negative, but the history of the knife industry is littered with people that make stupendous claims that turn out to mean bupkis.

[ryan1835]

friction forging sounds cool, i like friction welding myself

[Neil]

I'm with Magnus on this one.  I dislike reading a whole bunch of text like that without there being a whole bunch of references and peer reviews to go with it. 

Makes my spydie sense tingle .... 

[Raukodur]

Knives of Alaska Introduces DiamondBlade LLC and Friction Forged® "Super Blades"

Knives of Alaska Press Release

Tejon Ranch, California, USA - May 8, 2007: Knives of Alaska President, Charles E. Allen announced the formation of DiamondBlade LLC to manufacture extreme performance Friction Forged® "Super Blades." More than a dozen leading outdoor writers attended the initial product launch, held at the famed Tejon Ranch in California. This location was chosen because it provided an opportunity for the invitees to use one of these new "Super Blades" under actual field conditions - pursuit and field-dressing wild boar.

Research efforts, spanning the past decade, by Brigham Young University metallurgist and materials experts, Drs. Tracy Nelson and Carl Sorensen, with Friction Stir Processing (FSP) hard metals, laid the foundation for the new generation of Friction Forged® blades. According to Dr. Nelson, DiamondBlade's Friction Forged® blades are "probably the biggest legitimate improvement in the knife industry in over 40 years."

Drs. Nelson and Sorensen define a "Super Blade" as a knife blade that starts out sharper and stays sharp longer. Next the blade will have an extremely fine grain structure to offer enhanced resistance to abrasion (dulling). Additionally, the blade edge will withstand chemical erosion (rusting) even from strong acids and salt water. Finally, the blade will be differentially hardened, so that it withstands impact and structural stresses.

Extreme performance, Friction Forged® blades were conceived by Allen and Hobie Smith of Smith International in 2003, when formal blade and materials research efforts were begun. "Tests for evaluating blade performance characteristics were conducted using a CATRA (Cutlery Allied Trade Research Association) Razor Edge Sharpness Tester. Impact and edge strength, wear and abrasion, were also evaluated using machines designed specifically for those purposes. Edge resistance to corrosion was studied by coating the edge with 100 Nitric acid and immersion in salt water for several days. American Bladesmith Society's standards for their Journeyman knife forging test were also used," said Charles Allen. "Our goal was to construct a blade with a super sharp, long-lasting, corrosion proof edge that also had an extremely tough spine which makes breakage difficult. Simply put, we wanted to produce high performance blades that are superior to anything on the market."

Blade performance was described as "just unbelievable," by Durwood Hollis, a columnist for Tactical Knives and a regular contributor to Blade Magazine, after observing the laboratory and field tests first hand. "As a life-long hunter, I used literally hundreds of knives made from a wide range of materials, including all of the so-called "Premium Steels," and the Friction Forged® process develops an incredibly sharp, long-lasting cutting edge unlike any that I have ever seen or used," Hollis said. After using a Friction Forged® blade to field dress and skin several wild pigs, an animal with wire-like hair and grit-encrusted hide, Hollis was amazed that the blade would still shave hair like a razor. The performance characteristics of the Friction Forged® blade were truly revolutionary," Hollis added.

"Objective test results with hands-free equipment confirmed that the Friction Forged® blade edge lasts about 10 times longer than a standard (best processed) D2 steel blade," said. The key to the blade's extremely sharp and long-lasting edge characteristics result from the very fine, hard grain structures created within the steel by controlled frictional heat and extreme forging pressures. The Patented process exerts tons of downward force on the blade edge by means of a rotating Polycrystalline Cubic Boron Nitride (PCBN) tool, which creates frictional heating that "plasticizes" the D2 tool steel and then induces rapid quenching (cooling) temperatures.

Friction Forging®, through dynamic molecular shearing, "creates steel grain structure so fine, that it can only be seen with the aid of a Scanning Electron Microscope at 80,000 magnification," said Dr. Sorensen with BYU's Mechanical Engineering Department. "Normally, heat-treated and tempered blade steel grain structure can easily be seen with a standard 1,000 power microscope, but after undergoing the Friction Forging® process, the grain structures cannot be seen unless an electron microscope is employed." Sorensen went on to say.

Dr Tracy Nelson added, "Another benefit of the Friction Forging® process is the creation of a stainless edge zone that resists rust and even acid etching. D2 tool steel is high carbon steel containing enough Chromium to be stain resistant, but it is not classified as stainless steel. As the PCBN tool's frictional heat and pressure stirs and plasticizes the D2 steel, the Carbon, Chromium, Molybdenum, Vanadium and other elements within the steel go into solution. When the rapid quench occurs, some chromium is "frozen" out of solution, before it can all reform into Chromium carbides, thereby creating an observable stainless zone that is a trademark and proof that the blade has been Friction Forged®," Nelson said. Obviously, fine steel grain structure, a corrosion-resistant edge zone, higher edge hardness (65-68 measured on a Rockwell "C" scale) and differentially tempered (softer) blade spine are the keys to superior blade performance.

Chuck Karwan, a former U. S. Army Special Forces officer and West Point graduate, who has used all manner of knives for both combat and hunting, and who now writes for Tactical Knives and other publications, was stunned by a cutting performance demonstration he observed. "We tested the Friction Forged® blade performance by cutting through a 1/2" inch manila rope over 300 times. Amazingly, after all of that, the blade would still shave hair-easily!

We also tested the toughness of the blade, as well as the sharpness by chopping completely through a 2"x 4" board twice, then cutting through a free hanging rope multiple times with one swipe. Once again, the blade still shaved hair like a razor," Karwan said.

According to Karwan, the most "unbelievable" part of the Friction Forged® blade test came next. Many of the very best custom-made knives, as well as hand-forged Japanese swords employ a technique known as differential hardening." This results in a blade with a very hard, long-last cutting edge and a flexible spine that is very tough and somewhat flexible. With the correct geometry, such blades are virtually impossible to break, even when bent to 90-degrees. Knife blades that exhibit these characteristics are historically handmade, rare and extremely difficult to produce.

The "unbelievable" part of the Friction Forged® testing process that Karwan referred to occurred when after all of the cutting and chopping tests, he watched Master Bladesmith Wayne Goddard place the blade in a vice and bend it to 115-degrees without any evidence of cracking or edge failure. "This, as well as all the other tests, was undeniable proofs of blade strength and performance never before available at any price," said Karwan.

DiamondBlade is initially offering four different Friction Forged® blade styles, which will be referred to as their "Signature Series." Hobie Smith, VP, Smith International, Inc signs the "Pinnacle I" knife certificate. Charles Allen, DiamondBlade's founder, designed and signs the Pinnacle II and Summit certificates. The Goddard Traditional Hunter was designed and is signed by Wayne Goddard, Master Blade Smith and author of the book, "The Wonder of Knifemaking."

All of the knives are serial numbered, housed in a presentation box with an oiled leather sheath, and come with the signed Certificate of Authenticity. Standard handle scales are genuine Stag or Presentation Grade Desert Ironwood, Olive Drab G-10 is available by special order.

Unless all of these reviewers are either lying or naive knife users, the above quoted article seems to have good things to say about friction forged knives.

[Sea Monster]

Friction Forging?

More like FICTION Forging!

Amirite!?




Sorry, just woke up. It seemed clever in my head.

[J-sews]

Friction Forging?

More like FICTION Forging!

Amirite!?


Sorry, just woke up. It seemed clever in my head.

I'd give it about a 7 out of 10

[Raukodur]

We also tested the toughness of the blade, as well as the sharpness by chopping completely through a 2"x 4" board twice, then cutting through a free hanging rope multiple times with one swipe. Once again, the blade still shaved hair like a razor," Karwan said.

this seems quite amazing, since if true, it means the knife has good chopping ability, as well as cutting.

[Magnus]

We also tested the toughness of the blade, as well as the sharpness by chopping completely through a 2"x 4" board twice, then cutting through a free hanging rope multiple times with one swipe. Once again, the blade still shaved hair like a razor," Karwan said.

this seems quite amazing, since if true, it means the knife has good chopping ability, as well as cutting.

Any well made differentially tempered knife can do that though.  In fact that is part of the ABS master smith test.

friction forging sounds cool, i like friction welding myself

Friction welding is technically a forging process, so perhaps the process is similar (if it actually exists, of course)

Unless all of these reviewers are either lying or naive knife users, the above quoted article seems to have good things to say about friction forged knives.

A few things with this.

"Objective test results with hands-free equipment confirmed that the Friction Forged® blade edge lasts about 10 times longer than a standard (best processed) D2 steel blade," said.

Why has the entire results of this test been released then?  Why no lab reports?  Why no articles published in peer reviewed journals?

Friction Forging®, through dynamic molecular shearing, "creates steel grain structure so fine, that it can only be seen with the aid of a Scanning Electron Microscope at 80,000 magnification," said Dr. Sorensen with BYU's Mechanical Engineering Department. "Normally, heat-treated and tempered blade steel grain structure can easily be seen with a standard 1,000 power microscope, but after undergoing the Friction Forging® process, the grain structures cannot be seen unless an electron microscope is employed." Sorensen went on to say.

Perhaps it comes this fine, however if this is true then the will be no conventional methods to sharpen the knife back to its original sharpness.

[Raukodur]

since I have now got some free time, I am going to start some Ebay trading to make money, see if I can raise the amount needed for one of these without then having to feel guilty about it (unfortunately I am enamoured by the most expensive version - the Elan)

[Raukodur]

Quote
Friction Forging®, through dynamic molecular shearing, "creates steel grain structure so fine, that it can only be seen with the aid of a Scanning Electron Microscope at 80,000 magnification," said Dr. Sorensen with BYU's Mechanical Engineering Department. "Normally, heat-treated and tempered blade steel grain structure can easily be seen with a standard 1,000 power microscope, but after undergoing the Friction Forging® process, the grain structures cannot be seen unless an electron microscope is employed." Sorensen went on to say.

Perhaps it comes this fine, however if this is true then the will be no conventional methods to sharpen the knife back to its original sharpness.

I dont see why this is true. There is no 'magic' about this process, all it does is make the blade edge of the knife harder than the spine. You sharpen up the hard knife edge to get a good cutting edge which holds its sharpness, while the less hard, more flexible spine allows the knife to take more punishment without breaking.

Sharpening the edge would just be like sharpening any other knife which had a similarly hard edge. Use a diamon file or whatever.

[collantjay]

A diamond blade is a saw blade which has diamonds fixed on its base for cutting hard or abrasive materials. There are many types of diamond blade, and they have many uses, including cutting stone, concrete, asphalt, bricks, coal balls, glass, and ceramics in the construction industry; cutting semiconductor materials in the IT industry; and cutting gemstones, including diamonds, in the gem industry.

Mods note: I removed the link but left the message intact.

[Mr. Whippy]

A diamond blade is a saw blade which has diamonds fixed on its base for cutting hard or abrasive materials. There are many types of diamond blade, and they have many uses, including cutting stone, concrete, asphalt, bricks, coal balls, glass, and ceramics in the construction industry; cutting semiconductor materials in the IT industry; and cutting gemstones, including diamonds, in the gem industry.

Mods note: I removed the link but left the message intact.

I haven't banned the user, but removed a link in this post.  I don't see how this pertains to the thread.  I'd like to hear how it applies before doing anything further.  Collantjay?

[jzmtl]

It's just random spam. This type seems to be more common lately, less blatant and post in thread with certain keywords (like the URL in OP), with links to whatever they are selling.

[Whoey]

SFS flagged the IP of the user... account rejected.