Trouble understanding D2 properties

adrock1978

adrock1978

Joined
May 30, 2009
Messages
2,538
I don't quite understand the described properties and benefits of D2 steel, versus something like 1095. I read this quote somewhere:

These are two very different steels, pretty much night and day in properties. D2 is an extremely high alloy steel with a huge wear resistance and low toughness, while 1095 is a plain carbon steel with a very high toughness and low wear resistance.
Click to expand...

How can a steel have wear resistance, but not be tough? I thought D2, being a tool steel, was tough. Don't they use D2 for jack hammer bits and such? Is SR101 similar to 1095 steel? If I can maintain a 1095 knife and don't mind sharpening often, would it's toughness be a benefit over a D2 blade which keeps a sharper edge, but isn't as tough?

...and lastly, How many licks does it take to get to the tootsie roll center of a tootsie pop?
 
adrock1978
Grab a bag of popcorn and take this one over to the Makers section:D
One is oil hardening 1095 one is Air Hardening D2, you don't want to make D2 into a big chopper because it can be brittle(break) unless run way below a usefull hardness. But it will take a good edge and hold it almost for ever but is a pain to sharpen without diamond stones. D2 is lamost stainless.
1095 (which I have heat treated) will more likely bend then break and is easier to put a very sharp edge on but it will dull quicker then D2.
For Big choppers 1095 wins for small slicers D2 does. If I harden a piece of 1095 without tempering it back it can shatter like glass brittle but if it is properly heat treated go chop a cinderblock:p
 
.

Stay away from my Tootsie Pop!!!
Oooops, thought I was posting in the Horton forum, nevermind..............

.
 
Last edited:
Think of toughness vs. wear resistence like this:
Take a clay cup before you fire it in your ceramic oven. It's very maleable, you can smash it and mash it and it will never chip, break or shatter. Thats the idea of toughness, but with a better ability to hold form. So take that same cup and heat it up so it holds it shape, but not enough that it's hard. It takes more force to get it to move, but it'll still move before it breaks. It's starting to become "tough". That said, it has terrible wear resistance, you take some sand paper to it and it'll come off like clay, because thats what it is. It'll wear away quickly.

Now fire it. It's become a porcelin like ceramic, you can break it like glass, it chips and it shatters. It's not tough. But it now has excellent wear resistance - take some sand paper to it and it reacts like a rock, it takes a long time to wear away the material. It now has high wear resistance, but no toughness.
 
http://www.bladeforums.com/forums/s...f-Hunter-Utility-Knives?p=2152304#post2152304


JenniferBusse said:
Why D-2?

Hi guys! Eric is on the road right now and I wanted to take this opportunity to address some of the questions that have been raised concerning our use of D-2 tool steel in our upcoming series of hunter and utility blades. D-2 has recently gained a lot of popularity in the knifemaking community. Not surprisingly, Jerry (my husband) had used D-2 for many years when he was a custom maker. Recently while clearing out his original shop he decided to inventory his stores of bar stock. As it turns out, he had amassed quite a bit of his favorite tool steels including many tons of A-2 and D-2 tool steel. He put over 41,000 pounds of D-2 tools steel on the “For Sale” boards at over 90% off of the regular selling price! One of the deterring factors to using D-2 is its high price. Normally a 1/8” thick x 1 ½” wide x 18” long bar of precision ground D-2 Tool Steel costs $40.34 per bar. You can only get two 9” OAL knives out of a single bar. That means your raw steel cost per blade is over $20.00! That is over 3 times more expensive than using some of the other grades of cutlery steel!

Eric, called and asked about using the D-2 Tool Steel stock for Swamp Rat. Don’t you just hate when a great idea is sitting under your nose and you don’t see it yourself? Keeping in mind that Swamp Rat is all about saving Rat lovers money on high performance bladeware, I just couldn’t say “no” to the idea. After consulting with our production team on advantages and disadvantages of D-2 tool steel, we moved in and purchased over 30,000 pounds of the stock from Busse Combat.

Jerry is a big fan of D-2 blades when everything is done right on the knife. We have taken his advice on design, heat-treat, edge geometry, etc… and, in concert, with our superior Resiprene C handles will bring the finest, highest performance D-2 Tool Steel blades to the market. I asked Jerry to answer some questions about D-2 and here are his responses.

Why not stick with SR-101? And how does D-2 compare to SR-101?




Jerry:

“In the performance arena, it is nearly impossible to match what Swamp Rat is getting out of SR-101 in certain areas. The combination of incredible edge holding and toughness are unparalleled in the industry (except for INFI . . Sorry, I had to throw that in ;) ) . D-2 has a much better resistance to the elements in an uncoated or satin finished format than does SR-101. D-2 rivals ATS-34 for stain resistance and in fact proves to be nearly identical in this area in our accelerated salt spray corrosion tests. Surprisingly, or maybe not so surprisingly, the heat treatment and finish of D-2 can have a major impact on its corrosion resistance. When done properly, a D-2 blade requires minimal maintenance. Cleaning and oiling are a good idea but simply wiping the blade off and keeping it fairly dry will usually be all that is required for proper care.

In edge holding D-2 is an excellent steel and easily surpasses SR-101 when cutting harder materials such as steel banding, bone, etc. . . In soft to medium materials they are very similar in edge holding. In chopping and high impact applications, SR-101 easily surpasses D-2. Because of this, I do not recommend that any D-2 blades be longer than 5”.

In extremely thin edges, such as are planned for the Hunter/Utility line, D-2 will prove to be a superior choice. The same qualities that make SR-101 a great steel for abuse, play against the house when it comes to extremely thin cross sections. Under contact (cutting not chopping) with harder materials such as metal banding, bone, rock, etc. . . SR-101 will roll whereas D-2 will prove to be the clear winner in these applications. However, if you do any heavy lateral stressing on a thin cross sectioned D-2 blade, you may be glad that your Swamp Rat D-2 blade is backed by the best no BS warranty in the industry! ;)

D-2 also has a much greater resistance to high heat applications. What does that mean to you? Well, for us, as manufacturers that means that very fine edges can be satin finished with little worry of affecting the temper along the edge. This is not the case with SR-101, or any other simple “high carbon” steels, where extremely thin sections along the edge can be greatly affected by the heat generated from polishing.

So, in summary, for an uncoated blade with extremely thin cross sections, where cutting is the only intended application and hard materials such as bone, metal banding, etc…will be in contact with the edge, D-2 will prove to be a superior steel in edge holding and resistance to the elements.

In more abusive applications where cutting is to be coupled with prying, lateral stressing, high impact, and overall toughness, SR-101 will prove to be far superior to D-2.” --- Jerry Busse





So, when looking at the properties of these 2 steels you can see why we chose D-2 for our thin edged, bare metal, slicers.

Swamp Rat D-2 Tool Steel blades will prove to some of your favorite Rats. They will also stand as the only D-2 blades on the market that are covered against any and all major damage. . . :cool:

Thanks! :D

Jennifer
Click to expand...
 
adrock1978 said:
I don't quite understand the described properties and benefits of D2 steel, versus something like 1095. I read this quote somewhere:
These are two very different steels, pretty much night and day in properties. D2 is an extremely high alloy steel with a huge wear resistance and low toughness, while 1095 is a plain carbon steel with a very high toughness and low wear resistance.
Click to expand...

How can a steel have wear resistance, but not be tough? I thought D2, being a tool steel, was tough. Don't they use D2 for jack hammer bits and such? Is SR101 similar to 1095 steel? If I can maintain a 1095 knife and don't mind sharpening often, would it's toughness be a benefit over a D2 blade which keeps a sharper edge, but isn't as tough?

...and lastly, How many licks does it take to get to the tootsie roll center of a tootsie pop?
Click to expand...


The wear resistance of D2 comes from the carbides that form. D2 has more carbon than can fit into the steel matrix (~0.77%). The excess carbon is available to react with Chromium, Vanadium, and Molybdenum. D2 forms a lot of large diameter carbides.

These carbides are harder than steel. Think of it as concrete with the carbides as aggregate and the steel as the cement. When you cut, the steel wears away, revealing the carbides. So you end up cutting with the extremely abrasion resistant carbides and you get greatly enhanced wear resistance.

By the same token, the carbides act as failure points when you stress the steel. They are discontinuities in the matrix. So the D2 is not as tough as 1095, though 1095 is not the toughest of alloys. 1095 does not have great wear resistance.

To my knowledge, D2 is not used for jackhammer bits.

I can't comment on SR-101. I don't know enough about it.

Whether you prefer the somewhat tougher 1095 and easy resharpening to the much better edge retention of D2 will partly depend on how you intend to use the knife. I know at least one hunter who insists on D2 because he can skin several elk and not resharpen. I know others who like to baton their blades through wood, who prefer 1095.

Toughness is out of my ken.
 
So according to what I'm hearing, my Vex would make a great hunting knife. Typically when a steel is "tough" it can resist breaking from lateral stress? Are there any knife steels that posses the wear resistance of D2 but also have tougher qualities?
 
adrock1978 said:
Are there any knife steels that posses the wear resistance of D2 but also have tougher qualities?
Click to expand...

M4 will be tougher and hold an edge longer than D2. It is less corrosion resistant, though. I believe 3V also fits into that camp, with better edge holding and significantly higher toughness than D2.
 
cpm 3v,but you will get less corrosion resistance than d2. If you look on crucible's website the have a chart that shows the wear resist/toughness comparisons of diff steels .
 
adrock1978 said:
So according to what I'm hearing, my Vex would make a great hunting knife. Typically when a steel is "tough" it can resist breaking from lateral stress? Are there any knife steels that posses the wear resistance of D2 but also have tougher qualities?
Click to expand...

Right - while having read all of the above before replying my answer to your OP was that D2 doesn't resist lateral stress like 1095 (and some others) in certain blade lengths. Jerry Busse gave a good answer and you've reached the correct conclusion - it's all about rugged edge holding at the tradeoff of being weaker to lateral stress. I love D2 folders like my BM 710 D2 and my Hinderer XM-18 with CTS-XHP which Carpenter steel and other makers claim is D2 on steroids. It's more stainless than D2. :)
 
adrock1978 said:
So according to what I'm hearing, my Vex would make a great hunting knife. Typically when a steel is "tough" it can resist breaking from lateral stress? Are there any knife steels that posses the wear resistance of D2 but also have tougher qualities?
Click to expand...

I believe A2 tool steel would fill that role, its a lot easier to sharpen too.
 
You can get a comparison of 1095 vs D2 by watching the knifetests.com "reviews" of the Kabar 1095 and the Kabar D2. The handle designs don't fair too well, but how the blades perform is interesting.
 
knifenut1013 said:
I believe A2 tool steel would fill that role, its a lot easier to sharpen too.
Click to expand...
Wouldn't that suggest its edge wears easier then? If its easier to remove metal?
shunsui said:
You can get a comparison of 1095 vs D2 by watching the knifetests.com "reviews" of the Kabar 1095 and the Kabar D2. The handle designs don't fair too well, but how the blades perform is interesting.
Click to expand...

Oh cool. I'll take a look.
 
No, it has the wear resistance but its a "carbon steel" so other propertys of the steel are different. A2 is not 1095 easy to sharpen but its not as hard to grind as D2.
 
You must log in or register to reply here.
Back
Top