D2 and Corrosion Resistance

[DangerZone98]

If I may digress, I‘ve heard that D2 has a reputation for being difficult to sharpen. Is there any truth to this? My CS Leatherneck uses German D2 but I haven’t really worked it to dullness yet.

In terms of corrosion resistance though, I agree it holds up well.

 

[JPD1998]

I went on a D2 binge years ago and it definitely depends on who makes the knife.
Queens D2 will stain and patina. But Benchmade's doesn't.
Also I've noticed that D2 seems to pit before it actually rusts.

As far as sharpening , I touch up the blades on a ceramic rod, before they get completely dull.

 

[sabre cat]

If I may digress, I‘ve heard that D2 has a reputation for being difficult to sharpen. Is there any truth to this? My CS Leatherneck uses German D2 but I haven’t really worked it to dullness yet.

In terms of corrosion resistance though, I agree it holds up well.

I parted with my only D2 Benchmade last year.

Zero rust but, the knife was much more difficult to sharpen than the 154CM that I am used to.

 

[Pomsbz]

My Queen D2 took a patina in use and rusted with pickle juice. Not my Steel Will D2 though.

My Queen D2 would patina from vinegar or a couple of minutes in a cup of coke. It would also pit quite noticeably from salts. I had imagined that was what D2 did, I didn't know there were better grades. Good to know! I've wanted a Steel Will for ever.

 

[Larrin]

It’s not just the steel or even the heat treatment, but also the finish that is applied to the knife. The best finish for corrosion resistance is mirror polished and the worst is a coarse finish. There are some accusations that some D2 used in China is in fact a generic stainless. But I haven’t seen conclusive proof, only XRF measurements which do not include carbon content.

 

[FRNFanboy]

If I may digress, I‘ve heard that D2 has a reputation for being difficult to sharpen. Is there any truth to this? My CS Leatherneck uses German D2 but I haven’t really worked it to dullness yet.

In terms of corrosion resistance though, I agree it holds up well.

I haven’t had remarkable difficulty with it. It takes longer to sharpen than VG10 but takes a fine edge with out too much trouble.

 

[FRNFanboy]

My Queen D2 would patina from vinegar or a couple of minutes in a cup of coke. It would also pit quite noticeably from salts. I had imagined that was what D2 did, I didn't know there were better grades. Good to know! I've wanted a Steel Will for ever.

I punished Civivi and Ontario blades pretty badly without any effect, I was impressed.

 

[jbmonkey]

I have lots of various brand d2 knives. I've found it pretty darn rust resistant. I've rust spotted aus8 and 8cr13mov as examples of stainlesses in my sweaty pocket more than d2. benchmade d2 for anyone who wants to know which. I dont see lots of talk about d2's lack of corrosion resistance. maybe thats due to folks who like carbon steels and so this supercedes commonly used carbon steels in corrosion resistance? don't know......

 

[Chronovore]

I think it was Frankie from BirdshotIV that started the whole "D2 will rust if you look at it funny". While the corrosion resistance is nowhere near that bad, it isn't great.

I generally take care of my knives. I clean them and wipe them down with mineral oil as needed. Three seasons out of the year, I can carry D2 without issue. However, summers are very humid where I live. I tend to sweat too. Even with extra attention, I still get occasional spotting if I EDC D2 in the summer. This past summer, I decided to preemptively shelve my D2. After a little bit, I took out my Civivi Exarch, played around with it a little, and adjusted the pivot tension, checked for blade play, and put it back. The next time I did that, I noticed a spot on the blade. Upon closer inspection, I saw the culprit. I had left a lone fingerprint on that side of the blade when I previously checked for blade play...

Another issue to consider is that Chinese D2 seems to vary in both heat treatment and composition. I'm no metallurgist but I wouldn't be surprised if one blade in Chinese D2 had slightly better corrosion resistance than another.

 

[Sgt 127]

I carried a Bob Dozier Model six in my waistband for about 10 years in uniform.

I sweat. A lot. I’ve taken it out at the end of the day and water beads were all over it.

About once a week, I’d wipe it down with my current “this is absolutely the BEST rust preventative oil EVER!” (Usually Ballistol)

Every once in a great while I’d catch one or two tiny specks of rust.

That’s it. It’s a great knife and great steel.

 

[chalby]

I don't think it is nearly as bad as some people make out. I live in a tropical climate and in the summer when it is hot and humid, I do get small rust spots start appearing after a few days or a week on my Rat 2. These are easily removed, though I've never let it get too bad.

I have a QSP knife in D2 as well that I don't carry as often that seems a bit more resistant to corrosion. Having said that, I haven't really tested enough to say for sure.

 

[tsdevanna]

Larrin is correct. Also, heat treatment can have an effect on the corrosion resistance. The tempering temperature can be the culprit. I believe the best tempering temp for D2 is 500 degrees F - double temper - triple temper cannot hurt. Some people temper around 900 - 950 degrees F which causes a precipitation of secondary carbides - thus lowering corrosion resistance.

 

[chalby]

Larrin is correct. Also, heat treatment can have an effect on the corrosion resistance. The tempering temperature can be the culprit. I believe the best tempering temp for D2 is 500 degrees F - double temper - triple temper cannot hurt. Some people temper around 900 - 950 degrees F which causes a precipitation of secondary carbides - thus lowering corrosion resistance.

And would this precipitation of secondary carbides then increase wear resistance and edge retention at the expense of corrosion resistance and toughness? I'm guessing it is more complicated than this, but I find it very interesting.