420V vs. BG42 (corrosion factor?)

Dec 18, 1998

Curious to know which material will hold up better against corrosion.

My 440V bead blast kind of scared me a little with a few rusts spots.

Does the 420V kick butt on the BG42? It will be for a folder with about a 4" blade.


Big Dave: I am just starting to use 420V, so, my comments on it are based on specs and data from other sources, not my own experience. I have used BG42 for 4 yeats now, and I have never had a non-bead-blasted blade corrode in any way.
Both of these steels will probably be very similar in corrosion resistance. My spec sheet lists CPM420V at 13% Chromium, but, I believe they just kicked that up a bit, and that is the material I am working with. BG42 has 14.5% Chromium. It is important to remember that you can't base corrosion resistance on the Chromium content alone-it depends on how much of the Chromium is "free"-that is, not tied up with Carbon as Chromium Carbide. Crucible claims that the High Vanadium ties up a very high percentage of the Carbon as Vanadium Carbide ( A VERY good thing!),
and so the corrosion resistance of the 420 V is superior th that of 440V, even though the 420V has less Chromium.
So, my guess is that BG42 might be a little less Corrosion resistant than the 420V.

In either case, if you want to avoid rust spots, you should probably avoid the blast finish as well-particularly sand blast, as it makes deeper craters than the glass beads will. Remember, blasted blases have MUCH more surface area than polished blades, and thus are more subjest to corrosion.

Hope this helps. BTW, my Q-36 has about a 4" blade, and by years end, I'll have some in 420V. Right now, the BG42 is working awesome-all users of my knives have given favorable reports.

RJ Martin
mr dave....i will agree with the above post..am just starting to use 420v (its as hard as a rock by the way) but believe the corrosion factor will probably be about the same for a number of reasons....you cant load up stainless with too much without negative results...so they put in as much as they can to the point they are at now...most stainless' have between 12 to 14 points... also as he said...bead blast is a big nono for rust....stuff just collects in those little pockets...like humidity....mirror polish is the best antirust prevention..even on knives that rust readily....one thing to always remember...without iron we cant have a good tool steel...and iron is the thing that rusts in steel.....heat treat is a factor too....the harder the steel the more resistant to attack by corrosion.....
Thanks you very much for the input.

Glad to hear the good news about 420V.

Guess my only question is if the 420V would be worth the additional upcharge over BG42?

Mr. Martin, I keep checking your website to see what your new folder is going to look like. Bet you have something really cool planned. Will it be similar to the Q36?

Mr. Mayo, it's good to hear from you. I'd like to say that your (new?) gents folder is a sharp looking knife.

Thanks again,