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CRKT Crawford folder corrosion

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I have a fairly large folding knife with a stainless steel blade (Crawford Natural model) from CRKT that is about 10 years old. It had been sitting unopened in a dry, open location for over a year, possibly for as long as two years. To the best of my knowledge, it wasn't wet, or sullied with any corrosive agent when last folded and put away. I opened it a week or two ago, and was pretty upset to find significant rusty appearing pitting on both sides of the blade, considerably more on one side than the other. I wouldn't describe it as completely ruined. I think I can clean it up and resharpen it so that it can be used. However, it is compromised, and the most disturbing aspect ot the situation is that I make it a point to buy SS bladed knives for the express reason of preventing this sort of thing. I don't recall what SS alloy was advertised by CRKT for the blade, and the only marking I can make out appears to be "7085". Has anyone else had this experience with a SS knife from CRKT, or another vendor? Other thoughts?

UPDATE: This knife was advertised as using 8CR13MOV SS, which is a Chinese product supposedly equivalent to AUS-8. It is (or was) well-thought of by several manufacturers, and the relatively high chromium content should have provided good corrosion resistance. I wonder if there was a bad batch that I lucked into. 

A. G. Russell Knife Encyclopedia: 8CR13MOV STAINLESS STEEL

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Some people's skin oils are more corrosive than others.  Or maybe it was a super hot, humid day the last time you used/carried it, and you were sweating through a pocket.  Or you cut something corrosive and didn't clean it fully.  Or dust/lint on the blade attracted moisture. Or sat near an AC vent and somehow temperature fluctuations caused condensation. Or as you said, it could be a bad batch of steel or bad luck.

I probably still have at least 6 blades using that exact steel, with no more care than wiping it off against my jeans, with zero steel corrosion, all at least 10 years old.  My 8CR13MOV blades are cheap workhorses to me and have never been treated particularly well, and have been exposed to rainy days, significant amounts of box cutting, lots of sweat and humid days.  I've got nothing particularly bad to say about the steel, other than it IS Chinese, and edge holding obviously isn't as good as other more expensive steels.  I'd much rather have 8CR13MOV over 99% of the 4xx series stainless blades out there, so I don't think it is a bad steel at all.

I don't really treat the majority of my blades that specially, again wiping the blade free of fingerprints spine-first against my jeans a few times on each side.  Has worked for me so far, even for far more rust-prone steels.

 

If you'd like something truly rustproof, look into H1 steel.  My experience with H1 is that it can get very sharp but does tend to lose its edge faster than my typical EDCs with CPMS30V or VG10, though I think at least one of mine needed a complete reprofiling before it ever felt sharp enough.

Quote

Completely rust immune, great for use in salt-water conditions for dive knives and other water conditions. H1 is a PH steel, meaning it is a precipitation-processed alloy, that's rolled hard without heat-treating and has .1% nitrogen which acts like carbon, but does not react to chlorine to make rust. The edge can get up to 63-68 Rc and according to sources not become brittle. However, don't let the high Rockwell misled you, most consider the edge holding to be just under that of 8Cr13Mov or AUS-8. 
** from Spyderco "We don't publish Rockwell but I can tell you that it is in the high 50's , low 60's and all of our micro hardness testing shows that it is harder at the edge than at the spine because it is differentially work hardened so in a serrated version, the performance is much higher than a plain edged version."
Carbon (C) 0.15%, Chromium (Cr) 14.00-16.00%, Manganese (Mn) 2.00%, Molybdenum (Mo) 0.50-1.50%, Nickel (Ni) 6.00-8.00%, Nitrogen (N) 0.10%, Phosphorus (P) 0.04%, Silicon (Si), 3.00-4.50%, Sulphur (S) 0.03%.

 

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