Vanadium Chipping?

[Portholes]

I have been shopping for a high quality all purpose folder for months now and the latest one to catch my eye is the Spyderco Gayle Bradley. It is made with cpm m4 steel which is 4% vanadium. I know vanadium improves hardness and toughness, but a man I know who has much greater knowledge of blades than myself says that if you twist a vanadium steel blade while the edge is caught in something (ex. cartilage) a crescent shaped piece will likely break off of the blade. I would like to see if anyone has experienced anything like this and if it would be likely to happen with a 4% vanadium blade.

 

[Jason B.]

With extreme abuse anything is possible but M4 is a very tough steel and I highly doubt you will ever be able to harm it. I would ask this person you know to show you this "problem" because I highly doubt it happened. Lots of myth surrounding the "super steels" and most of it is false.

 

[DennisStrickland]

m4 is able to take a very thin edge w/o chipping or deformation. in fact my info says it is one of the toughest high r.r. alloys commonly avaivable. formites have used it hard in the field & praised the results. this steel can corrode but if you wash & dry blade oxydiation is not likely. i use 1095 all the time & only have a patina no rust. if i could find enough models & low cost i would have this steel in 90% OF MY KNIVES. the new steels with great heat treats have gotten around earlier problems of high chrome, van., tung. problems. remember twisting cuts with any thin edge is something knowledgeable users advoid.

 

[Portholes]

Thank you very much for the replies. My friend probably had an older knife without modern heat treating. And I don't plan to make twist cuts, I just want my knife to be able to handle them if the situation dictates.

 

[gunmike1]

My CPM M4 Mule took apart a 400 lb hog, including cutting off the lower legs at the knees and cutting off the head without chipping. It was still cutting effectively once the job was done, and it was literally hours of work. CPM M4, especially with Spyderco's heat treat (my Mule is 62.5 RC), is very tough with excellent edge retention and great sharpness potential. It is currently my favorite blade steel, as not even S90V or ZDP 189 impress me as much as CPM M4's great combe of toughness and resistance to chipping, edge retention, ability to take and hold thin and acute edges, and especially because it gets sharper easier than any other steel that I have tried. My last 2 folder purchases were the M4 Benchmade Rift limited edition and the Bradley in M4, and I am on the wait list gor the titanium Reeve Integral Lock M4 Spyderco Military due in May. I will most likely get the Rift and Bradley re heat treated to 65 RC by Phil Wilson to see the jump in edge retention I can get from pushing M4 to it's limits. From my experience even losing a little toughness to get an extra few points of hardness won't be enough to make M4 chippy, even at pretty thin edge geometry. As for losing a huge crescent shaped chip in M4, on a thin edge in any steel if you get a knife buried deep in say a piece of wood and twist out of the cut you can get a giant chip, especially on a very thin hollow grind (as in much thinner than the Bradley), but in a hard wood buried deep enough even a factory folder can get a chip taken out that goes all the way into the primary grind. Generally this takes a very dumb move of knife abuse to bring a chip like that, so if you use your Bradley folder as a knife you will be extremely happy with it's performance.

Mike