Corrosion Resistant Steel

[samuel082799]

I want to make a dive knife and i was wondering what steel is the least corrosive.

 

[Stacy E. Apelt - Bladesmith]

Most stainless steels are more than sufficient. 440C would be fine.

If you want the max, use 1/4" thick titanium. Titanium is very different in grinding and finishing, so read up if you think that sounds good.

 

[tim37a]

Either Elmax or M390 are going to be the best. Beta titanium can be hardened to about 45 Rc but I think it takes special equipment and processes. You can buy a very good Ti dive knife from Mission Knives.

Tim

 

[Matt Rochester]

I agree with 440C. I made a knife for a fella that works in and around fresh water all day everyday. It has held up well. Also, you see a lot of oyster knives in 440C and they hold up well to the salt.

 

[Alpha Knife Supply]

Nitrogen steels like N360, N680 and Z-FiNit have much better corrosion resistance than standard stainless blade steels.

Here is a photo comparing N680 to 420 after salt spray testing:

As you can see in the photos, nitrogen stainless steels have extreme corrosion resistance.

Chuck

 

[me2]

Any idea how that 420 stainless was heat treated? Or the N680?

 

[rustyrazor]

Any idea how that 420 stainless was heat treated? Or the N680?

treated badly if they were spraying salt on it

 

[d00mtr33]

Out of regular stainless steels its 12c27, cts xhp, m390, s110v
Even better are nitrogen steels like 14c28n, n680, z finit, cronidur 30, n360 and if you can find vanax 35 and nitrobe 77 (my precious).
But id think most stainless steels would be ok if you take care of your knife by applying a rust preventing agent like froglube or corrosion x or something alike and wipe and dry your knife after you're done. 440c is still a standard that most steels are compared to in corrosion resistance for a reason.

 

[DevinT]

Nitrogen steels like N360, N680 and Z-FiNit have much better corrosion resistance than standard stainless blade steels.

Here is a photo comparing N680 to 420 after salt spray testing:

As you can see in the photos, nitrogen stainless steels have extreme corrosion resistance.

Chuck

Yup, nitrogen steels is the way to go.
Hoss

 

[Matt Rochester]

Are we talking fresh or saltwater?

 

[Alpha Knife Supply]

Saltwater

Chuck

 

[Mahoney]

well it's not steel, but cobalt alloys like stellite are also used to make corrosion resistant boat and dive knives

 

[Stacy E. Apelt - Bladesmith]

I made a bunch of dive knives from David Boye's dendritic cobalt. I didn't mention it because the supply is small and it is expensive. IIRC, there are still a few cobalt dive blades in the blade drawer.

 

[Wolf_HR]

And I believe H1 steel as used on Spyderco knives is as rust resistant as N680... I'm a bit puzzled by the info I've seen, but I think it should perform wll enough if used by a reputable knife company...

 

[Matt Rochester]

Saltwater

Chuck

I never saw where the op stated which one. In my opinion lots of stainless would be fine for freshwater. Salt is another story.