80CRV2 Problems

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Mack1775

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Alright I usually don't like to ask for help about heat treating steel because of the amount of info out there and self testing, but I'm at my wit's end with this stuff. I usually work with 5160, 1084 and O1 every now and then, so when I saw Aldo Bruno had some 80CRV2 I picked some up. I tried a number of things and even talked to Daniel Winkler about it. I've tried hardening it at 1485, 1500, and 1525 degrees with 10-20 minute soaks using vegetable oil or McMaster oil. No matter what variation I try I end up with a metallic marshmallow. If anyone has any idea why this is it would be greatly appreciated.

-Mack
 
Did you normalize it? Some other deep hardening steels that have been totally spheroidized need a trip up to 1700 or so to break up those carbides.
 
80CrV2 is 1080 with .5% chromium and .2% vanadium, There isn't any excess carbon or high alloy content to really have to deal with in HT. It is basically tough 1080.

What it does have that may be an issue is lower manganese ... only about .5%.
5160 has about twice the manganese, which is why it hardens easily in even a bad quenchant.

It won't hurt anything to run a high temp cycle as you would do for 52100, like jmd suggested, but I don't think that is the issue. Follow that by a standard HT at 1500°F with a ten minute soak. Quench in fast oil (Parks #50) or brine. It should come out of quench at Rc63-64.
The pearlite nose on 1080 is very shallow (less than 1 second), and the quenchant has to be fast and of sufficient volume. I would expect 80CrV2 to be equally shallow, maybe even shallower.

What I do with any steel that isn't acting like I feel it should is do a quench test. I take a coupon about 1X2" and HT it with a brine quench. That will give me the maximum expected as-quenched hardness as a base line. If my HT of the blade is significantly lower than the test, something is wrong in the HT.
 
When you say vegetable oil, do you mean canola? I haven't worked with 80CRV2 as much as other carbon steels, but the few I have made from it were heat treated by ramping slowly and soaking at 1500 - 1550 F for about 6-8 minutes and then quenched into warm canola oil. They come out just as hard as 5160 or 1084 would. It's very unlikely if it's from Aldo, but from time to time there are "bad batches". I have had a bad batch of O1 before that just wouldn't harden at all. Like I said though, if it came from Aldo, a bad batch is slim to none. Could it be the transition from heat to quench? How long was the blade out in open air before it was submerged in the oil? My vote is to make several heat treat coupons - use some of them to see if they key is normalizing first, and the rest to find out if the heat treatment itself needs to be adjusted.
 
You may be tempering at too high a temperature for it. After talking with Ben Tendick at the Gathering, I dropped my tempering from 400 degrees to 350 degrees and built this test knife: http://www.bladeforums.com/forums/showthread.php/1341466-80CrV2-camp-knife-testing I'm quite happy with the results.

I normalize three times after forging, then harden at 1550 degrees, quenching into 130 degree canola. Then three tempering cycles at 350 degrees for an hour each time. Pretty simple. You can get more complicated and really push it. Check out the March 2015 issue of Blade Magazine for an article by Joes Szilaski on how he got it to do 2,000 cuts on 3/8" manila rope.
 
Chad,
This is an old thread. I think he has finished the project. Please read the dates on any thread you pull up in a search. Resurrecting old threads is called Necroposting. If you see an old thread and want to know about something in it that applies to a knife you are making, or a question about the info in the thread, it is best to start a new thread and link the old one in your question.

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