Hello everyone,
I am getting ready to make my performance test knife out of 80CRV2 and am having (what I consider) severe issues with getting it to harden. I would like to run through my process to see what I am missing. I bought the steel from a reputable supplier, forged it out to .180", normalized it at 1650 using my Evenheat oven, let it cool to black. Ran it back up to 1500, let it soak for 5 min., cool to black. Ran it to 1425 for 5 min. and cool to black. Surface ground it to .170", cut it into 1-1/2" x 1-1/2" coupons, welded on a tail to grab the coupon with my tongs to eliminate any contamination with the sample, and polished each to 400 grit. I did 5 different heat treat/quenches. 1525, 1510, 1495, 1480, 1465. I may have been a little "hot", but I also failed at this previously and figured maybe my oven was not as hot as it says. On each one, I ran it up to temp. the first time, let it soak for 10 minutes, quenched it in Gloc A oil for a 5 count. Decarbed using an A100 grit belt, ran it back up to temp. again, let it soak for 2 minutes and requenched for a 5 count. My Gloc A oil was in a tank that I have added a heater and fuel pump to circulate the oil. Oil was anywhere from 98 degrees to 110. Decarbed again, polished to 400 grit. My hardness tests were anywhere from 26 points to 31. I would, maybe being naive, thought that I would be somewhere in the middle 60's? Put both of my sample blocks in the tester and they were within 1 to 1-1/2 points. I initially thought maybe I wasn't being fast enough to get the sample from the oven into the oil so I spent 20 minutes to 1/2 hour before I started trying to get my speed up. I am right about 2 seconds from the time I open the door until the coupon hits the oil. I must be missing something, just cannot figure out what it could be? Any help on this would definitely be appreciated. Thanks!
Frustrated in South Dakota
I'm not familiar with that particular quenching oil but 80CrV2 steel doesn't need anything super fast (like parks 50)
I would suspect first that you haven't gotten through all the decarb or scale. It can go deeper than you think, especially with that steel.
Try grinding some more off and test again.
I treated it just like 5160 and it performs very well.
I've always wanted to try that oil for the deep hardening steels, but haven't needed any.
Don't confuse "decarb" with scale. When you say you "decarbed" what you did was simply grind off the iron oxide "scale".
Something you might do is bring your oven up to 1550.
Put in a small coupon and soak for maybe five minutes, after you are certain the steel is up to full heat. You always need to allow time for the steel to equalize to the oven temp.
Quench in a five gallon bucket of water swirling the steel around constantly so you're always touching water.
It should be like a piece of glass.
If so, you'll know you're getting it hard.
I know that when using my Texaco A, which is equivalent to the Gloc A, I always heated it to 135 as it is a super slow oil.
The time getting from the oven to the oil is not the critical part of hardening, it's the time getting the steel from the austenizing temp down below the temp at which it can still convert to pearlite.
Karl B. Andersen
Journeyman Smith
Hello Joel maybe I can help. 80crv2 is an excellent blade steel, I used it for my js performance test and passed. Forge at 2200. Three normalization cycles with reducing heat starting at
1600 the around 1450, and last bellow critical or around 1350. I use a 10 to 12 second or a medium quenc like duratherm g , I was told not to use parks 50. Austinize at 1500 with a 10 min soak. Quench in 80 degree quenchant. Agitating the steel for around 30 seconds. Temper at 425 for one hour and at 415 for one hour. My blades come out at a 59 Rockwell,
It's important to test to destruction. Plan on wasting some steel. Also break some to check your grain it will tell you a lot . Also it's important to blue back your spine twice if your blade cracks
It can't crack a third of the way up the blad or it will fail. I was told that 80crv2 is similar to L2 . Hope this helps
Scott.Holler at me any time
I love this steel.
One of the things I've noticed and have had it confirmed from some other smiths is that no matter what it decarbs deeply.
The first few times I hardened it I would hit it with a file and the file would cut for a long time and then all of a sudden it would skate like ICE!!!!!
So try grinding a little more off than you usually do with any other steel.
Ok, my process.
Normal forging. I treat it the way I treat 1075.
I cycle it 3 times, once at at least 1600.
Once in the range of 1500-1550 and then I do a sub critical normalization.
When I harden it I use Mcmasterr 11 second oil and heat the steel to around 1500 in the kiln.
Let it soak for a few minutes and then quench until I cannot hear cavitation remove count to 3 requench and then into temper at 400 for several hours.
This process I used for a cutting comp knife that did the 2X4 no problem with no chipping or roll, cut through a golf ball and did the rope cut perfectly.
I did everything except the bend test.
I've made several more since then all the same process.
Good luck with your test.
Thanks for all the help guys. I have a good direction to head and you have all helped me immensely. Karl, as always, you do a very good job at explaining.
Scott, I met you down at Kansas City with Steve. Once again, congratulations on your journeyman.
I am a pretty consistent lurker here, so HI.
I love 80crv2, but like everyone else says it decarbs badly. Expect to remove some metal, and I suffered the same issues as you. What has really helped me is an anti-scale wash. It has made all the difference on that steel, well all the steels actually. Good luck can't wait to see your results.
I know it's a "zombie thread", but.... I have been getting around the deep decarb issue by using SS foil wrap for the normalization cycles, then removing it for the Aus cycle. MUCH thinner decarb layer to deal with, and no scale. Hope it helps
