Need advice on heat treating 80CRV2

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Keanen

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Nov 21, 2024
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Hi guys. Hope you had a great Christmas!

I have been having some problems with heat treating my 80CRV2 in my kiln. I'm testing my blades with rockwell testing files and they seem to be coming out softer than they should. 60 is biting. I heated my oven to 1580 and let it preheat for 15-20 minutes. I put the blade in and soaked it for 15 minutes before quenching into 125 degree Parks 50. I thought it seemed softer than it should have been out of quench (65 bit, 60 skated but left scuffs), so I tempered at 300 degrees for 1 hour x2. My parents got me a ceramic heat treating rack from Housemade for Christmas and I am wondering if maybe I need to give it more time to heat up and that could be affecting the heat treat? (I had it preheating with the oven.) However, I had some blades that I hardened before the rack that failed chopping into deer bone and a brass rod test. I got rolling on the edge. So, I am thinking it is something with my recipe.

I appreciate any help you can give me.

Happy New Years!
 
Mostly, you are doing fine. Two minor issues will up your hardness.
1) Parks #50 is not used at 125°F. It is used at room temp.
2) Grind the blade surface clean before testing. there is a layer of soft decarb on the surface after HT.
 
Stacy E. Apelt - Bladesmith said:
Mostly, you are doing fine. Two minor issues will up your hardness.
1) Parks #50 is not used at 125°F. It is used at room temp.
2) Grind the blade surface clean before testing. there is a layer of soft decarb on the surface after HT.
Click to expand...
Ok, thank you. I ground off quite a bit and it's still soft, so I am not thinking it is decarb.

After posting my question, I realized that the blades that rolled when I did the brass rod test were quenched in cooler Parks (probably about 70-80 degrees). They were also soft.
I am wondering about retained austenite? What are your thoughts on that?
 
Seedy Lot said:
Buy some 80CrV2 from AKS and you will have zero issues.

1525°F for a 12-13 minute soak. Parks 50 quench. I repeatedly get 60-61 Rc with a 400°F temper, 61-62 Rc with 375°F temper a ans 62-63 Rc with 350°F.
Click to expand...
Thanks, that's my plan moving forward. Do you have any suggestions for working with the steel I have right now?
 
Look up the knife steel nerds article on 80 CRV2. I go through the full normalizing, grain refinement, DET anneal and then I believe it's 1525 for 10 minutes and quench. Different steel suppliers sell the steel in different conditions, alpha knife Supply is typically ready to quench. Stuff I get from other suppliers, I go through the normalizing and other processes. Processes that way if I forge or do stock removal I get the same results.
 
Where did you buy the 80CRV2? If it came from NJSB it is spheroidized and needs to be normalized and DET annealed.

Normalize at 1650F soak 10-15 minutes then air cool
DET anneal at 1400F soak for 30 minutes then cool to 1200F at a rate of 600F/hr
Austenitize at 1525F soak for 12 minutes
Quench in room temp Parks 50
Temper at 325F 2hrsx2
61-62Rc

Be sure to foil wrap the steel when normalizing and DET anneal
 
NJSB had a batch of 80CrV2 go out a while ago (maybe a year plus?) that many well seasoned makers couldn’t get to harden. The problem was never really acknowledged, but if you bought your steel from NJSB a while ago, maybe something to think about.
 
Keanen said:
Thanks, that's my plan moving forward. Do you have any suggestions for working with the steel I have right now?
Click to expand...
I would follow what Cypress Creek Knives Cypress Creek Knives says. I would do the same but I have not yet used my NJSB 80CrV2 just their 52100 with excellent results after normalizing and a det anneal.

I have only used AKS 80CrV2 and every time I have over the last few years ht results are always the same.
 
It's really interesting to know that you guys can remember specific batches. I had no idea the same steel could require a variety of recipes depending on the dealer.

Being a knifemaker sounds horrifying. How do you crazies remember all of this?
 
Stacy E. Apelt - Bladesmith said:
Mostly, you are doing fine. Two minor issues will up your hardness.
1) Parks #50 is not used at 125°F. It is used at room temp.
2) Grind the blade surface clean before testing. there is a layer of soft decarb on the surface after HT.
Click to expand...
👆This 👆
I was going nuts trying to figure out why I wasn’t getting the results I wanted. Then someone told me to grind off a decarb layer and I was so relieved that I forgot to feel dumb for not thinking of it myself.

The decarb layer isn’t too thick but it’s enough to screw up a file test.
 
Keanen said:
Hi guys. Hope you had a great Christmas!

I have been having some problems with heat treating my 80CRV2 in my kiln. I'm testing my blades with rockwell testing files and they seem to be coming out softer than they should. 60 is biting. I heated my oven to 1580 and let it preheat for 15-20 minutes. I put the blade in and soaked it for 15 minutes before quenching into 125 degree Parks 50. I thought it seemed softer than it should have been out of quench (65 bit, 60 skated but left scuffs), so I tempered at 300 degrees for 1 hour x2. My parents got me a ceramic heat treating rack from Housemade for Christmas and I am wondering if maybe I need to give it more time to heat up and that could be affecting the heat treat? (I had it preheating with the oven.) However, I had some blades that I hardened before the rack that failed chopping into deer bone and a brass rod test. I got rolling on the edge. So, I am thinking it is something with my recipe.

I appreciate any help you can give me.

Happy New Years!
Click to expand...

Ok I tried best to replicate your ht treat today using Steel Barron 80CrV2. It is cold here and I was only able to heat my 4 gallons of Park 50 to 109°F.

First Rockewell check with only surface grinding the bottom side so I could see what decarb was like, 62-63 Rc.

After I ground of 0.010 inches 64 Rc.
 
Just a note abbot Parks #50 oil temperature.
While it will work at 120°F, it is designed with a RANGE of 50°-120°. It woks optimally at room temp- 70-80°F.

If you start at the max temp of 120°F, it is counterproductive.

This is the info from two knife supply ompanies that sell Parks suppliers:

#50 QUENCH OIL Low viscosity quench oil that approaches water in quench speed, yet gives a more uniform, less severe quench than water. Recommended for open quench system operating below 120°F.
The recommended operating temperature range is ambient to 120°F.

50 QUENCH OIL is as effective at 50°F as it is at 120°F because of its low viscosity. This is a big advantage to many steel treaters who have oil quenching tanks without heaters.
 
Taz said:
Look up the knife steel nerds article on 80 CRV2. I go through the full normalizing, grain refinement, DET anneal and then I believe it's 1525 for 10 minutes and quench. Different steel suppliers sell the steel in different conditions, alpha knife Supply is typically ready to quench. Stuff I get from other suppliers, I go through the normalizing and other processes. Processes that way if I forge or do stock removal I get the same results.
Click to expand...
Thanks a lot. I went ahead and normalized and annealed like you suggested, following the recipe that user Cypress Creek suggested and I was able to get a much harder blade from that. Moving forward, unless I purchase from Alpha, I'll be sure to cycle and anneal them. Thanks for your reply!
 
Cypress Creek Knives said:
Where did you buy the 80CRV2? If it came from NJSB it is spheroidized and needs to be normalized and DET annealed.

Normalize at 1650F soak 10-15 minutes then air cool
DET anneal at 1400F soak for 30 minutes then cool to 1200F at a rate of 600F/hr
Austenitize at 1525F soak for 12 minutes
Quench in room temp Parks 50
Temper at 325F 2hrsx2
61-62Rc

Be sure to foil wrap the steel when normalizing and DET anneal
Click to expand...
Thanks for the reply. It was purchased from Pop's. I went ahead and followed your heat treat recipe and I'd say that 65 rockwell left scuffs, but didn't bit in. It was definitely much harder than previously. I think it came out nice after temper, but I'll let you know how it does after I do some testing. Thanks a lot!
 
Cliff Carter Knives said:
NJSB had a batch of 80CrV2 go out a while ago (maybe a year plus?) that many well seasoned makers couldn’t get to harden. The problem was never really acknowledged, but if you bought your steel from NJSB a while ago, maybe something to think about.
Click to expand...
Thanks. I still have steel that I purchased from Pop's and NJSB (this particular bar was from Pop's) that I'm working through, but I'll be purchasing from Alpha moving forward to hopefully avoid these issues!
 
Seedy Lot said:
I would follow what Cypress Creek Knives Cypress Creek Knives says. I would do the same but I have not yet used my NJSB 80CrV2 just their 52100 with excellent results after normalizing and a det anneal.

I have only used AKS 80CrV2 and every time I have over the last few years ht results are always the same.
Click to expand...
Thanks, I went with Cypress Creek Knives Cypress Creek Knives recipe and it worked great. I got much better results. I appreciate all the help!
 
For stock removal, it's nice to just be able to austentize and quench! I mix some forging with mostly stock removal, so I do the full process to make sure they are consistent!
 
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