D2 steel

[The Mastiff]

Jax, D2 bumped up in vanadium to the same amount as S30V's is called D7. They also had to add more carbon to get the vanadium carbides they wanted ( had to go up from 1.5% to 2.5% carbon to make those wear resistant vanadium carbides). Other than the Carbon and vanadium they pretty much look the same. You get a very wear resistant steel, but it's not tough at all due to the composition. Remember this isn't a PM steel with the benefits from that ( smaller grain and a bit tougher)

The D series steels, plus others: http://www.nsm-ny.com/index.cfm?fuseact ... page_id=28

Note: the graph above on that page has wear resistance and toughness of the steels talked about with the exception of S30V. The Graph has D2 to compare it with, D7 obviously, as well as other goodies like Cruwear, CPM 3V, CPM D2 ( powder steel D2), 10V ( A11, of which K390 is a modified form.) The website is excellent and has some great info. They purchase huge batches from the foundries ( like 80,000 lbs), roll the steel to sizes needed and sell it to lots of knifemakers,factories, amongst other industries. They are really good people. There are other graphs for CPM steels, high speed steels, common knife steels, etc.

There is one other company I know of that makes a powder D2 product under a different name. I have no information if any more CPM D2 is being made. I do know that Crucible finally did get a second heat made after having at least one whole heat fail during production. After that epic fail ( descriptions of it made it sound like it looked like the aftermath of an explosion :) , though it wasn't naturally, it was just a big , expensive mess) there was speculation about whether there would ever be more made. There was, though I don't know about current plans.

A heat of 81-83,000 lbs of steel can last a very long time in the knife industry if there are no other buyers. I have no idea if current production CPM D2 stock, or knives in production is from the second heat, or if there have been more. It's never really been a heavy use steel. In fact, Kershaw has used it for the spines of knives they make brazing two steels together into one blade. They have also used it for the edge, using 14C in the spine.

Joe

[Jax]

Good info,thanks joe!
To be honest I have been curious about D7 for awhile in relation to blade steel.
I noticed it when scouring through steel types,and it's composition jumped out at me,having ground D2 before I knew that D7 must be a beast.
Someone mentioned awhile back that steel like D7 is why the PM process was developed,to give a more homogenous structure that lent itself to easier grinding and working during production.
If I am not mistaken D7 would be harder to grind/mill ect.. Than any A11 class Pm steel despite the lower alloy content.
I have only seen one knife made of D7,and it was of course a full custom.
Agreed that d2 and some other's of the D family of air cooled tool and die steels aren't the toughest,and admit it's curious when i see it used in big choppers or survival/fighting knives,or as a blade spine in the composite kershaws you mentioned.
D2 must be tough enough for most knife applications (the low toughness is relative) because it can and does receive impact forces when being used in coining,shearing,stamping/die ect ect...
But having said that I would rather have my D2 at the cutting edge,and my 14c27at the spine :)

[gull wing]

Thank you, this knife is hard not to like.
Haven't tested it yet, but I guess will depend on my heat treat.

[Tabo]

*This is my own experience, your mileage may vary.* I never had any good times with D2. I could never get a razor sharp edge from it plus it would start to rust on me from sweating in the summer months when carried in the pocket. I try to stay away from it for blade steel, but if I really like the knife, I would let it slide.

[Pocket Lint]

Cool thread!

I would like to add my experience with D2 steel. I bought a Bob Dozier Buffalo River Hunter in D2 steel back in 2007. Since that time, I have brought it with me on canoe trips and even dunked it in the river. I have had no issues with D2 until recently. Back in March of 2013, I went on a winter camping trip as part of my school curriculum. During the 10 day camp, we did activities such as hunting, skinning, and butchering caribou. We also did other activities such as planning and conducting an aerial survey, setting a fish net under ice, radio telemetry, and a 2 night, 3 day winter survival course (temperatures dipped down to -40 Celcius!).

I skinned about 3 caribou with my D2 blade, and also killed a caribou by inserting my knife into the base of the skull. I noticed very quickly by the 8h day that my knife had developed spots of rust on the blade and also along the edge. The blade also had chipped all along the edge, with rust marks surrounding the chips. During the skinning process, I had also cut through thick bony leg joints, so I suspect that is how the edge chipped.

My initial thoughts on this steel are a bit disappointing. I had paid $215 dollars for this knife. The corrosive resistance is poorer in my experience compared to other steels that I have owned for longer (VG-10). Although the knife came with an extremely sharp edge, and held it fairly good considering the uses I put it through, I would rather have a tougher steel with better corrosive resistance.

Despite my initial disappointment with D2 steel, I still find it to be a good all around steel. I likely will not ever sell my Bob Dozier hunter because of the fact that I killed my first caribou with it and the sentimental value it holds. It is still a great knife, and handles very beautifully.

Link to knife

http://www.agrussell.com/dozier-buffalo ... hhh334GLM/

[Melektau]

I have a kabar d'eskabar that I bought to try out d2. I use norton india stones and can get a edge sharper on the d2 than any steel I have from 1095 to zdp 189. It sails through notebook paper so quietly that you cant hear a sound. Maybe you are not getting to the apex of the edge. What are you using to sharpen it with and to what angle? I go around fifteen degrees per side wirh no trouble.

[Melektau]

I would think when used in industrial applications, it would be used much thicker than the edge of your blade.

[RanCoWeAla]

I almost bought a DPX folder at the Blade Show that had D2 but I thought that overtravel screw needed some work so I passed it up. The overtravel screw is supposed to lock in place and make the knife like a fixed blade only the one I picked up wouldn't unlock and to unlock it requires a special tool which I wasn'too crazy about.

[Donut]

I thought the screw for tightening the rotoblock was just a hex.

[gull wing]

Well I tested my knife for long enough to know I like D2 (on this knife).
It's fairly easy to sharpen, gets very sharp(which is a MUST), and holds the edge well. I don't have a hardness tester but, followed the specs sheet to arrive (I think) at the hardness, 61-62. With little attention to rust, it looks great still. I do wipe it after use and sometimes touch it to my forehead(oil). That's all!

This is a good, low priced steel, with great qualities, will use it again.

I am well pleased!

[Doc Dan]

My favorite skinning knife is made from this steel. I also have a hard use folder from Benchmade made from this steel. I recommend it highly. A similar steel I have high hope for because it is a bit more rust resistant is CTS-XHP.

[gull wing]

Yes, I would like to get my hands on some CTS-XHP.

[SpyderNut]

^^^ Me too. Although I'd also like to try CPM S35VN on one of my folders.