What to expect from D2 steel? (Rant included)

[TC]

I have two Bark River Highland Specials in CPM-D2. Never seen any other knives in that variant, though, for whatever reasons. Because the user one (the other is still NIB) gets very, very sharp indeed, and I haven't had any corrosion issues so far.

 

[Deino]

There are a few issues here. First, the market isn't flooded with D2 as people sometimes understand it. The reputation for that steel was built by American or other knives using that steel with a reasonably good heat treatment. What has been flooding the market in recent years are mass-produced budget knives made with Chinese D2. There has been some question on the quality, purity, or consistency of that steel. In XRF testing, the vanadium content seems to vary more than it should and is often on the low side. There is also the issue of the mass-production heat treatment. Some companies do better than others but usually, the actual edge retention just won't live up to that reputation.

The latter issue also affects a lot of the 440C we see today. Yes, companies still use 440C. Sometimes, it is used in niche or custom knives that might get a good heat treatment. However, a lot of it gets used in very inexpensive budget knives from companies like Ganzo or QSP where it probably doesn't.

The market has moved up on the budget end but it depends on where you look. While the Chinese-made knives from Kershaw or CRKT might be stuck in the past on steel, lots of Chinese companies are offering better budget steels at competitive prices. Steels like 9Cr18Mov, 14C28N, and even Chinese D2 are usually a good step up from 8Cr13Mov, 5Cr15, 420, etc. There is more that can be said about that but I'll leave you with one other thing.

Toughness isn't just about how easy it is to break your blade. It can also affect your edge. Another issue is grain structure and that helps with steels like 12C27 and 14C28N. The following article may be helpful.

What is Edge Stability? - Knife Steel Nerds

Thanks to Keith Nix and Benaiah Brabant for becoming Knife Steel Nerds Patreon Supporters! The vote is still open on Patreon for what equipment will be purchased for future research. Edge Stability I got help directly from Roman Landes in writing this article (Thanks Roman!). The content below...

knifesteelnerds.com

That's exactly my point. If you go most retailer sites and sort by steels, you will see that D2 has a much wider offer than any steel nowadays by a significant margin. Hence I see that as a flood. And again, 440C started out as a reputed material that gets corner cut by Asian makers, to offer lower price, which hit both the reputation of the quality steel and the reputation of the quality product.

On one end, 5Cr15 is the composition name for a while range of 420HC alike, defined mainly by having over 0.45%C and around 14%Cr, including the German nomenclature range of 4116, 4110, 4034, which are still used widely used by European countries. On the other end, 9Cr18 is probably their 440C that people got and hated in the past, nothing new, but different name gives different impression, a rebranding of the "cheap 440C" phase nothing less. The end knife snobs awe at the steels then looks at better production but lesser steels "oh, they are collectible knives, not use knives". With the corner cutting in many productions, Chinese companies use better steel to make up to the abysmal production.

Also, I never talk about toughness about breaking the whole knife. As I said "tougher shape", in knife world could be thicker blade or grind, to avoid chipping issue, which is to maintain better toughness and edge stability, however you want to see it, though less sharp overall.

(Here is a reply email after I asked QSP through their website contact about their 440C)

 

[The Grendels]

Because D2 has become the "it" steel for budget knives trying to bridge the gap to higher quality knives, you're seeing a lot more variability in the quality of heat treatments from knife to knife and from what I've read there is more chance of variable heat treatments with a steel like D2 than something like Aus8.

When Andrew Demko or Benchmade put out a knife with D2 steel it's something to look forward to. If it's a budget knife being shoveled into a massive oven a thousand at a time, I'm a bit more apprehensive. With Buck knives I feel confident about the heat treatments of knives made in the US, but have no confidence in their oversight of the heat treatment process overseas. Any Boker Magnum (their budget line) or Boker Plus (intermediate) using 440 steel is a red flag for me, but I don't have as much of a problem with their D2. Spyderco can make a good knife anywhere and I have no concerns about their quality control or oversight issues, although they seem to be allergic to D2. A Cold Steel D2 knife, made before the GSM acquisition, is something to be interested in. I wouldn't feel the same about a new GSM release in D2. I'm not going to have any confidence in Gerber D2 blades no matter where they're made, even if they swear they're lovingly crafted by magical monks from Shangri La. Knife buying for me is always going to be a balance between steel and blade geometry, handle ergonomics, knife company and origin, and the knife designer.

 

[midnight flyer]

Because D2 has become the "it" steel for budget knives trying to bridge the gap to higher quality knives, you're seeing a lot more variability in the quality of heat treatments from knife to knife and from what I've read there is more chance of variable heat treatments with a steel like D2 than something like Aus8.

As with just about any other steel and any other maker. How do we know, I mean really know, which steel we get? Sure we read what they promise, but this argument about D2 has been going on for years. And the definitions are wide and varied. No doubt, it is the same way with other steels.

And how to account for human error?

"You know, I think that batch of XXXX super modified full race stainless steel of the day might be a touch soft. Should we use it?"

"Yeah, it falls within acceptable parameters. That was the day Phil was out and Mike was on the furnace. It should be OK."

Inquisitive eyes here on BF have even caught manufacturers ( Merkan, ones, too) switching steels. On purpose? Human error? Stuff happens?

Although this thread is pretty tame, I am always surprised at how belligerent the knife community is about steel knowledge, how it is handled, how that steel is treated by a manufacturer literally 10,000 miles away in a factory they have never visited. Sure, Google fu is now nearly an Olympic sport, but we are at best at the mercy of manufacturers of knives to give us what we were promised.

My experience with D2 is mixed. Since it was mentioned in this thread, 440C as well. But the thinking while I am typing my experience with almost all steels varies from manufacturer to manufacturer. I have 440A on old Kershaws that is harder than the S35 on my ZTs. And the D2 on my two Queen knives that have it is something I would buy above all other steels. It has a super fine edge when polished and holds it well. But even the D2 on my Kershaws is different from the two knives I have with it. To me, it is nearly the luck of the draw.

 

[Chronovore]

That's exactly my point. If you go most retailer sites and sort by steels, you will see that D2 has a much wider offer than any steel nowadays by a significant margin. Hence I see that as a flood. And again, 440C started out as a reputed material that gets corner cut by Asian makers, to offer lower price, which hit both the reputation of the quality steel and the reputation of the quality product.

On one end, 5Cr15 is the composition name for a while range of 420HC alike, defined mainly by having over 0.45%C and around 14%Cr, including the German nomenclature range of 4116, 4110, 4034, which are still used widely used by European countries. On the other end, 9Cr18 is probably their 440C that people got and hated in the past, nothing new, but different name gives different impression, a rebranding of the "cheap 440C" phase nothing less. The end knife snobs awe at the steels then looks at better production but lesser steels "oh, they are collectible knives, not use knives". With the corner cutting in many productions, Chinese companies use better steel to make up to the abysmal production.

Also, I never talk about toughness about breaking the whole knife. As I said "tougher shape", in knife world could be thicker blade or grind, to avoid chipping issue, which is to maintain better toughness and edge stability, however you want to see it, though less sharp overall.

(Here is a reply email after I asked QSP through their website contact about their 440C)

While there are some differences, 9Cr18Mov is at least similar to 440C. Of course, that also assumes a lot about whatever QSP (or whoever) is calling "440C". I've never seen any kind of controlled testing on their 440C but from my personal experiences, I wouldn't recommend it. Most of the 9Cr18Mov I've had lately has been noticeably better.

9Cr18Mov is a steel I actually used to "hate on". I'd had a couple of cheap knives in it from the likes of CRKT and I was not impressed. Since then, I've had a bunch of other knives in it and I've also seen a bunch of testing on it. It turns out that the current 9Cr18Mov from Real Steel or even Schrade is solidly "okay" (especially once past the factory edge). Meanwhile, the 9Cr18Mov coming from WE (Civivi, Sencut, Ferrum Forge) is in another class. They've perfected the heat treatment, much in the way that Buck has (via Bos) on 420HC but from a better starting point. The edge retention on WE's 9Cr18Mov tends to be better than Spyderco's VG-10.

The irony is that in perfecting the heat treatment on 9Cr18Mov for their budget knives, its edge retention becomes competitive with their higher end knives in "super steels" that get mediocre heat treatments. A lot of the S35VN and M390 we see in production knives just doesn't meet expectation. Starting with a known quantity on those steels, it definitely seems to be an issue of mass-production heat treatment.

While that issue affects a lot of Chinese production knives, it isn't exclusive to China. Lots of companies could do a better job on heat treatments. As far as other forms of quality, that definitely depends more on company than country. Generally, you'll see pretty good machining and actions from the Chinese companies with better reputations, such as Reate, WE, and Kizer.

 

[Deino]

While there are some differences, 9Cr18Mov is at least similar to 440C. Of course, that also assumes a lot about whatever QSP (or whoever) is calling "440C". I've never seen any kind of controlled testing on their 440C but from my personal experiences, I wouldn't recommend it. Most of the 9Cr18Mov I've had lately has been noticeably better.

9Cr18Mov is a steel I actually used to "hate on". I'd had a couple of cheap knives in it from the likes of CRKT and I was not impressed. Since then, I've had a bunch of other knives in it and I've also seen a bunch of testing on it. It turns out that the current 9Cr18Mov from Real Steel or even Schrade is solidly "okay" (especially once past the factory edge). Meanwhile, the 9Cr18Mov coming from WE (Civivi, Sencut, Ferrum Forge) is in another class. They've perfected the heat treatment, much in the way that Buck has (via Bos) on 420HC but from a better starting point. The edge retention on WE's 9Cr18Mov tends to be better than Spyderco's VG-10.

The irony is that in perfecting the heat treatment on 9Cr18Mov for their budget knives, its edge retention becomes competitive with their higher end knives in "super steels" that get mediocre heat treatments. A lot of the S35VN and M390 we see in production knives just doesn't meet expectation. Starting with a known quantity on those steels, it definitely seems to be an issue of mass-production heat treatment.

While that issue affects a lot of Chinese production knives, it isn't exclusive to China. Lots of companies could do a better job on heat treatments. As far as other forms of quality, that definitely depends more on company than country. Generally, you'll see pretty good machining and actions from the Chinese companies with better reputations, such as Reate, WE, and Kizer.

Thanks for your input on the 9Cr18Mov. My QSP wasn't even in their 440C/9CrMoV, but in D2.
Old steels are still being used under alternative nomenclature standard that the companies want market it as. Sometimes, it is simply because the popular name is tainted, so they switch to a different name. Though, I think about it, the misinformation from the past might associate with the fact that people don't have many way to share and discuss about the information/data, or the assumption of same steel name = same quality. With everything available on the internet nowadays, the incorrect info can be weeded out and therefore preserve the reputation of the the steel much better than before.

Cheer.

 

[Pacu0420]

I think title says it all.
Also, how hard is it to sharpen? Comparable to 3V?
(Yes, I have diamond sharpeners).
Feel free to skip the rants below if you're in a hurry.

I currently have 2 knives and I needed another one.
But, I am becoming a student, so price plays major role in my decision making.
I'm kinda late bloomer, but like my friend on here of similar age (almost same bday) I'm also paying my own education.
Now forgive me for unneecessary rants.

I was looking at budget knives and was cringing at 5Cr...8Cr...9Cr... 440...420... and AUS steels. I might be a steel snob but well.

So I was drawn to D2 (for some reason it's calling me for a long time). And I couldn't decide over Boker GoBag or Manly Patriot. So I just ordered both.

So Warcraft Tanto and Esee 3 are forrest/camping knives.

Manly Patriot and Boker GoBag are EDC. I opted for D2 because it's fairly stainless and holds a good edge (I like toothy edges) plus for some reason something is drawing me to D2.

Your opinions are greatly appreciated.

D2 is a good steel. It does take a bit longer to sharpen. I've found that is doesn't want to let go of the burr. I use the Work Sharp Precision Adjust with a strop to finish. And I sometimes feel like pulling my hair out while sharpening D2. Patience is the key. Which is something I lack. 154cm is a great alternative as I've found it to be a breeze to sharpen and usually doesn't cost too much more than D2. Just my opinion.