Alternate carbon steel?

wolffbite

wolffbite

Joined
May 7, 2010
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As a lot of you know, I've worked pretty much exclusively with O-1 since I started knife making earlier this year. I try to search and find answers as much as I can on my own without posting new topics... but I wanted some specific input for myself in this case.

I'm thinking of switching it up away from O-1, because I'm getting awfully frustrated with the pitiful corrosion resistance it has. I have fairly oily fingers, and I tend to stain all of my finishes during the final stages of a knife... and it is really a pain to carefully go back and lightly re-sand things to get rid of rusty fingerprints.

I still really like carbon steel however, and don't want to stop using it. So I'm looking for a more corrosion resistant alternative, and would like a few opinions.

Option 1: A-2

This option has roughly 5% Cr content, which is miles beyond O-1 already. And depending where I source my steel, the composition is roughly the same (Cr excluded)

Option 2: CPM-D2, or D-2

This option is approaching stainless all together at around 12% Cr content. I'm not quite sure on the differences between the regular D-2 and the crucible versions. I would appreciate if someone can shed some light on them?

I'll probably hear a lot of mixed opinions, so I'm curious to see how many of you guys use these types of steel and what applications they excel or don't excel at.

As for applications... I would like to start designing a few more choppers, so my steel choice would have to be suitable for knives over 12".

It seems I can get any of the 3 at roughly the same price precision/Blanchard ground which is what I require/prefer (no surface grinder). So once the rest of my O-1 is used up, I want to order something else.

I exclusively send out for heat-treating as well, so that is not an issue.

If someone can recommend another carbon steel that is available PG/BG and has better corrosion resistance than O-1, and open to suggestions!

Thank you very much for your help in advance! :)
 
From what I have heard, D2 is about as near stainless as you can get. If you are sending it out for HT, then it may be your best option.

However, I have never used it, so maybe someone with better experience will chime in.
 
I love A2.

Have you tried wet sanding with wd-40 or something?

After I've glued on handle slabs, often before shaping, I wax the blade with Flitz gun & knife wax. painters tape won't stick very well after that, but if you wrap it several times it works ok.

-Daizee
 
there's a mod here on the forums with that very problem, I just think he wipes them down good after handling them..

pending how bad your situation is, I'm not sure if either of those steels would be full proof.. but definitely better then what you're using now..

There maybe a better answer to your problem then changing steel.. as Daizee suggested..
 
If you like O1's cutting performance, try 13C27 or AEB-L. All three will take very fine edges, but the last 2 are stainless.
 
wolffbite said:
I'm not quite sure on the differences between the regular D-2 and the crucible versions. I would appreciate if someone can shed some light on them?
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D2 in general doesn't rust quickly like O1 can, nor does it take a nice patina. When it does get to corroding, it tends to little scattered pits rather than red blossoms all over it. The CPM-D2 has a finer, more consistant structure, which gives you a bit more toughness. It definitely takes a nicer finish, without the "orange peel" or mottled look so common to regular D2 when you try to handsand it to a high degree. If you can get them at close to the same price, I would definitely go for the CPM version.

I haven't worked with A2 but based on the specs and reports from lots of makers, but I think I would choose it over D2 for 12" plus knives, it's just plain tougher. It's somewhere between O1 and D2 for corrosion-resistance.

Give Aldo a call and see if he will PG some CPM-3V for you. 3V is extremely tough with very good edge-holding. It's corrosion resistance is similar to D2, it will pit a little but generally won't straight-out rust like O1 can. Passivating 3V improves this to a degree.
 
For someone looking for a substitute for O1, I don't think you're going to like D2. I love D2, but it is very different from O1. It has large carbides and high abrasion resistance which makes it more difficult to work with and the heat treat required to achieve good fine edge stability is complicated (and most of the folks you can send it out to don't do it very well for cutlery applications). It is pretty far away from O1.

I think that A2 would be a great substitute for you for O1. Another perk is you can take it thinner before HT because it distorts less in HT. I have found it to be about the same in difficulty working it.


About the only advantage that O1 has over A2 that I'm aware of is it takes a better patina.
 
I love this place :)

Thanks for the responses so far guys.

I did switch to wet-sanding with WD-40 and it does help, but my main problem arises once the knife is handled after finishing. I always do a coat of mineral oil, but that doesn't seem to last long when handling for taking pictures and whatnot. Perhaps I need to get some wax or beeswax as daizee said.

me2 thanks for the suggestions, the odd time I've used stainless I used CPM-154 and didn't mind it. If I do a bit more with stainless later on I might give those a try.

Thanks for the info Nathan. It looks like A2 is probably my best bet at this point

Now to see what aldo can do for me on finding some ;)
 
If Aldo can't help you (and he probably can) I know you can get PG A2 from MSC and Enco.
 
Nathan the Machinist said:
For someone looking for a substitute for O1, I don't think you're going to like D2. I love D2, but it is very different from O1. It has large carbides and high abrasion resistance which makes it more difficult to work with and the heat treat required to achieve good fine edge stability is complicated (and most of the folks you can send it out to don't do it very well for cutlery applications). It is pretty far away from O1.

I think that A2 would be a great substitute for you for O1. Another perk is you can take it thinner before HT because it distorts less in HT. I have found it to be about the same in difficulty working it.


About the only advantage that O1 has over A2 that I'm aware of is it takes a better patina.
Click to expand...

hi nathan

about the D2 experience, i think her large carbide can be refined by solution treatment.

i do not remember the exact temperature, but the general carbide refinement is done by solution at acm+50~150°C, holding for enough time(for a knife size 30mins believed to be enough), gas or oil quench. this way you get a full martensite structure with no extra carbide. then temper the blade at somewhere arround 720~740°C for enough time. during the tempering the carbide will precipitate from the tempered martensite, or called tempered sorbite. these precipitated carbide usually at the size of supper fine. and the structure after 720 tempering will be soft enough for mechining.

also by doing the solution treatment, it may cause the big grow in grain size. to countering that, you might need at least one grain refining quench before the final Q&T. the final quench and tempering is the same as the normal one.

also due to the high temperature required by solutioning. you might need anti-decarb coatings. i am not sure how much it is in US. but its pretty cheap here, about $20 per kg for the grade can resiste decarb up to 1200°C. and you can use it for like at lesat 20 1 meter size swords.

factories reported that tools of cr12Mo1V1 (aisi D2) doing the double refinement(solution and cycling quench) has great increases in tool life than the usual anneal-quench-temper.

i will check the exact solution conditioning temperature they used in factory(1060 C+/-10 i think, but i have to make sure). well you might have already know these all.
 
Wolff, try a surface treatment that dries, like the Flitz wax (goes on like car wax) or something else.
I do NOT recommend straight beeswax unless you have a buffer, love it as I do for other things. It can soften at inconvenient temperatures, then harden up again, solidifying prints or whatever. It's good on a natural wood handle, tho.

You could also try using cheap disposable rubber gloves. I do that when I've got a bad cut or something that shouldn't be filled with sanding dust.

I vote for A2 anyway. It's really neat stuff. IF you've got access to an oven, the HT is easier than O1 since there's no liquid quench! And it's impossible to over-temper in home heating equipment.

-Daizee
 
I'll give the Flitz wax a try thanks daizee!

I have probably 20 or so blades to complete out of my remaining O-1 so it will be a bit. But I'm definitely going to A-2.

Another bonus I just realized... my heat-treater doesn't do oil-hardening above 12" (not like I make too many over that length anyways) because of his quench tank, so air hardening will let me go up to 20" blades... I sense some choppers in my future!
 
So it looks like you use the same HT place I do. Rob does good with D2, and the stuff comes back so clean you would be amazed. If you ever do give D2 a try take it to a fairly high pre HT finish if you don't you will find out just how abrasion resistant D2 is
 
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