1095 various quench medium hardness test results: Brine, Houghto-Quench k, Apco K-9,

[Jeff the Millwright]

My plan was to practice freehand bevel grinding on some cheap steel but instead of using 1080 I got the brilliant idea to try and see if I could make some hamons so I ordered some 1095 and W2 from Canadian Knife Supply which I was told by them is from Aldo which didn't end up being so brilliant, lol.

From reading the site I learned that these steels need a very fast quenching medium in the 7 to 9 second range. Being in Canada the only way to get Parks 50 was to have it shipped from Texas so I thought I would do some hardness testing using different mediums and testing them with my hardness tester to see if the Parks was really necessary.

In my initial tests I did Brine, a 9 to 11 second oil I got from a local heat treating company for free made by APCO and canola oil all between 130 and 140°F. Just for curiosity I did the 9 to 11 second oil at room temperature also.

My sample pieces were half inch sections cut from a 2 inch by .170 piece of 1095. I have an Evenheat oven with a tap controller. I placed my four pieces in the oven and then ramped up to 1475 and soaked the pieces for 10 minutes.



I tested each sample piece multiple times along its length avoiding the end were my tongs were. I was surprised at the variation along its length. I am thinking this may be due to variations in scale buildup or perhaps uneven bubbling? I know it would be easy to assume my hardness testing is not accurate but whenever I calibrate it with my test piece that came with the unit my reading are within less than one unit accuracy.



But here are my results:

Brine: 64.5, 66.3, 65.5, 66
APCO 9-11 second oil: 54, 60, 65, 65,
Canola Oil: 50, 59, 52
Room Temp APCO 9-11 second oil: 46, 53, 44

The Brine gave me about the results I was hoping for because I had read that a maximum hardness on 1095 after quench was about 66 which in my mind validated that my process was proper.

I was actually surprised that the 9-11 oil gave me up to 65 but the lower numbers down to 54 with it were disheartening and made me think perhaps it was from bubbles forming in some areas or uneven scale as mentioned before. If there is one certainty from this test is that Canola oil isn’t up to the job.



The fact that there was such a difference in the 9-11 second oil between the heated and room temperature tests made me think that perhaps there was a sweet spot so I did a further test using this oil at 130°F, 160°F and 190°F as its maximum temperature is 190°F.
130F: 64, 63.5
160F: 60, 61.5, 63.5
190F: 59, 60
The results were mixed but indicate 130°F looks best but compared to a brine quench I am losing approximately 2 Rockwell hardness points so I figured I would invest in a good 7-9 second oil hoping to get back into the 66 range without the risk of cracking from Brine.

I picked up some Houghto-Quench® K - Houghton at a distributor in Stony Creek in the Niagara region of Ontario. I would give the distributor’s name but I think anyone might want to look at the results before they pick up this stuff.

Just to save on steel I reused the pieces from my previous tests after I did three normalizing cycles in my tests for the Houghto-Quench® K - Houghton. I had pretty dismal results at the three temperatures I tested at which were 140°F, 160°F and finally 180°F. I thought maybe the poor results were from my normalizing cycles so I did a final test using new steel and after reading the only posting on this site about the best temperatures for this oil was between 125°F and 150°F I took the average which was 137 ½°F.

These are the test results using Houghto-Quench® K - Houghton. Again I ramped my oven up to 1475°F which took about one half hour and then soaked it at that temperature for this time 20 minutes to make sure the carbon was fully disbursed.



I took six readings three on each side along the length.

They are: 58, 59, 53, 56, 57, 57

Obviously these are pitiful hardness's for a 7-9 second oil which I was under the impression from reading on this site that I should be getting close to the 66 hardness I got with Brine. This is very disheartening considering I paid almost $300 for this 5 gallon pail that isn’t as good as the 9-11 second oil I got for free.

I have a sneaking suspicion that this oil is mislabeled and is not Houghto-Quench® K - Houghton but one of their slower oils? My question is has anyone actually ever tested either 1095 or W-2 using Houghto-Quench® K - Houghton and if so what were the results. Or my other question is does anyone have any suggestions as to what could be my issue?

I know there may be a suspicion that my methods are sloppy but I have been a millwright for almost 30 years where I have spent my career dickering with things and troubleshooting. I really can’t see my methodology being at fault especially since my Brine quenches where so good but I am definitely open to criticism. I would love to get to the bottom of this because I really don't know where to go from here? I think I was given the wrong oil mislabelled but how do I prove that? And if not if I spent the money to have Parks 50 shipped up here would i get the same dismal results? Maybe I should just go back to stainless because in the long run it would have been cheaper to practice my grinds on it, lol.

 

[Willie71]

Did you grind through the decarb before testing? Secondly, what thickness was the steel? While 1/4" steel should/could through harden, you might have a soft core.

For comparison, I got low to mid 60s with heated canola, and get consistent Rc67/68 with W2 in DT-48, similar to parks 50.

Oh, I use 1460 for W2. I did a bunch of tests a while back, and going up or down by 10f resulted in less hardness and less consistency.

 

[Jeff the Millwright]

Yes Willie I did grind the decarb off using my 2×72 grinder but at quite a low speed as not to heat up the pieces. The steel thickness is about .180 so I doubt if I have a soft core plus using the same steel and method I was able to get 66 using Brine so I doubt those are the issue.

Those are pretty amazing numbers with heated canola considering I couldn’t even hit 60? But thank you for the input. I really think the fact I could get such good numbers with Brine makes me think that this isn’t really Houghto-Quench® K - Houghton but instead one of their slower rated oils mislabeled.

Either that or no one has ever really tested with a hardness tester their results with Houghto-Quench® K? And what is the best quenching oil temp for Houghto-Quench® K - Houghton but I can't really see that as my whole issue?

 

[P.Brewster]

This is a great thread. I encounter a lot of people who think that heat-treating is a matter of heating to non-magnetic and quenching in whatever.

Agitation is the only thing that comes to my mind as a possible variable for future trials.

Companies like Houghton are able to quantify quenching speed very accurately. Test results for each oil are posted on the spec sheets - such as http://www.houghtonheattreat.com/pdf/cold-quench-oils/Houghto-Quench K.pdf

If I understand correctly, the "classic" way to measure quenching speed, which you used in your post, is the "GM Quenchometer Speed," which is explained here http://www.machinerylubrication.com/Read/430/quench-oils and here http://www.asminternational.org/doc...p060.pdf/f160fe44-c38d-460e-9fce-4a4d07790df8

It would be great if there was an affordable and repeatable way for knifemakers to measure the quenching speed.

 

[Jeff the Millwright]

Thank you Brewster for your comment that this is a great thread because the frustrating part is that I definitely did my homework on 1095 and W-2 and what the proper quenching agents are only to get pitiful results, LOL.

And I appreciate your input on agitation but I don’t really see that as being the possible issue because with these shallow hardening steels one has to get over the nose in less than half a second which really doesn’t leave any time for agitation.

Honestly I don’t see what I could have done wrong so I am left with the only conclusion that I was given a slower oil that was labeled as Houghto-Quench® K - Houghton but if someone can find the error in my thinking or process I would love to hear it.

 

[P.Brewster]

You say they are pitiful results - I know you'd like to see values in the mid 60s, but your results really aren't that bad (for the Houghton at least).

When I first got my hardness tester, I went through the exact same experience - I treated and tested a bunch of pieces of steel, only to learn that (a) the hardness is 1-6 RC points lower than I was expecting, and (b) the consistency was much worse than I imagined. The testing process itself is somewhat finicky and inconsistent (speaking for myself at least).

I think this is a big reason why production shops such as Peters cryo everything.

I think most knifemakers who aren't outsourcing the heat-treating do not have a proper hardness tester. I speculate that your experience is more commonplace than it may seem.

In general, I think it is essentially impossible for an oil to be as fast as brine. Perhaps my logic is flawed, but it seems the fastest oil out there will be a few RC points lower than brine. So if you're getting 65 RC from brine, I would say 63 RC is a good benchmark for the Houghton K.

Another idea is to try a different steel - something with a good amount of manganese and/or moly.

 

[Tom Lewis]

I went through a similar situation awhile back. I thought I was grinding off all the decarb, but I wasn't. When I finally did grind off all the decarb, I got the RC hardness I expected. I sympathize with you, this can be very frustrating.

 

[Kentucky]

D.Crawford posted results for 1095 quenched in McMaster carr fast quench here a few years ago that averaged around 65rc for 1/8" stock..1475° aust temp if im not mistaken.

 

[Kentucky]

http://www.bladeforums.com/forums/s...-actual-results-for-mcmaster-carr-oil-on-1095

 

[Jeff the Millwright]

I think you are right Brewster because I began my heat treating using a homemade natural gas heat treating oven hooked up to a pyrometer and I thought I was getting decent results until I bought my hardness tester and found that my results were actually all over the place, maybe ignorance is bliss, LOL.

And yes you are also right in that consistency is much worse than I imagined even on a single piece. I do use dry ice on my stainless but haven’t considered it for plain carbon steels but I might check that out in the future too to see if that gives me any more consistency. Despite my current frustrations I actually enjoy the investigative process so I am determined to improve my results what is really frustrating me is that I paid almost $300 for 5 gallons of oil that isn’t doing what it is supposed to.

I could live not getting maximum hardnesses but what really has me thrown is that I got 66 with Brine and 65 with a 9-11 second speed oil but with the 7-9 second Houghto-Quench® K - Houghton which should be in the 66 range I was only in the upper 50s?

I really think I was given the wrong oil but I have no way to prove it so I’m going to have to probably just swallow the financial loss so now do I get Parks 50 for another $300 counting the shipping and brokerage fees and exchange rate? I think I might call Houghton tomorrow and see if I can talk to someone and maybe they have some wisdom.

 

[Jeff the Millwright]

Thanks for your suggestion Tom Lewis. I might try grinding a little more off and seeing if I get any higher numbers but I am doubtful because I ground off the same amount as when I was getting 66 with the Brine but it is definitely worth a go so thanks for the idea and sympathy, LOL.

And thanks Kentucky I had a look at that page and you are right about the McMaster Carr being in the 66 range. One guy on the same thread said that he got 66 to 67 using an 11 second oil which is hard to believe and that sure makes my 7-9 second Houghto-Quench® K - Houghton results pretty dismal.

I have actually looked at every single posting I could find on this site about Houghto-Quench® K - Houghton and everyone says it is equivalent to Parks 50 but no one seems to have any actual hardness tests using it so maybe people assume it’s the same because it has the same rating but maybe it’s actually junk it’s just that no one has tested the results.

Either that or as I say and suspect I was given different slower oil improperly labeled as Houghto-Quench® K - Houghton?

 

[P.Brewster]

I wouldn't give up on the Houghton K just yet. If they did send you the next slowest oil, G, it should still work since it is a 10-12 second oil. http://www.houghtonheattreat.com/pdf/cold-quench-oils/Houghto-Quench G.pdf

I've used plenty of Parks 50 and I felt the same way about it as you do about Houghton K.

Right now I'm playing with Houghton 3699, which is a polymer/water-based concentrate. If you want total control over your quenching speed, consider trying this - dilution rate determines cooling speed. At a 15% solution, I'm getting the same RC values as I was with Parks 50. Houghton suggested I start at 12.5% to match a fast oil speed, but it seemed too violent.

 

[Willie71]

Another thought is the starting condition of the steel. Aldo's steels are course spheroidized, giving inconsistent heat treat results. I normalize to break up the carbides the. Thermal cycle to refine the grain. I got tired of scratching my head with unexpected results, and the cycling gives me what I expect within 1 Rc point. W2 and 15n20 come out exactly where I expect, 1095 a bit less consistent, but within 1 point.

 

[P.Brewster]

I have actually looked at every single posting I could find on this site about Houghto-Quench® K - Houghton and everyone says it is equivalent to Parks 50 but no one seems to have any actual hardness tests using it so maybe people assume it’s the same because it has the same rating but maybe it’s actually junk it’s just that no one has tested the results.

I've toured and done business with a saw blade manufacturer who uses Houghton K exclusively, mostly on 8670 steel. If I remember correctly, they are getting 59-60 RC post-quench on 8670.

 

[jdm61]

I am not sure about the Houghton stuff, but Park# 50 is designed to work between like 70 and 100F which for me means don't heat the the durn stuff except for 2 days in January here in Florida. The 11-13 second Houghton which a number of people like Brownells repackage, supposedly has a range of 120-180F and the 11 second sweet spot at 150F.

 

[Jeff the Millwright]

The Houghton 3699 sounds very interesting. I really like the idea of being able to totally control your quench speed through dilution. Too bad I didn’t hear about that before I bought my Houghto-Quench® K or whatever the hell it is they sold me, LOL.

But unfortunately I think you are right in that it is probably their G class oil. Because I have some 9–11 second oil and it is faster than what is supposed to be the Houghto-Quench® K - Houghton. But G is only good for eutectoid steels like 1080 because they have a shallower nose but they are just not fast enough for a hypereutectoid steel like 1095 and W-2 with such a steep nose that I am using.

 

[Jeff the Millwright]

That is a good point Willie about the spheroidized steel from Aldo and that is why I brought it up to temperature in the oven which took half an hour and then gave it a 20 minute soak to try to disperse the carbon. And that may definitely be part of the problem but what makes me doubt that is my whole issue is that when I used brine I got 66 hardness without thermal cycling or normalizing.

I may definitely experiment with that in the future but I don’t think that can really explain my dismal numbers with the Houghto-Quench® K - Houghton. Besides I did try some normalized samples that I thermal cycled that I used in previous tests and I still got extremely substandard hardnesses using the Houghto-Quench® K - Houghton. That’s why I went back and used a fresh piece.

 

[Jeff the Millwright]

Yes jdm61 I like the fact Parks 50 can be used at room temperature; just eliminates one more procedure.

But yes I did use the Houghto-Quench® K - Houghton at quite a range of temperatures; 140°F, 160°F, 180°F, and finally 137°F and didn’t hit 60 at any temperature so I don’t think my issue is temperature alone.

I appreciate all the suggestions and they are all making me think that it probably is not the proper oil but I am going to try to call Houghton in the next couple days depending on my schedule to see if they have any suggestions.

 

[kuraki]

Using Parks 50 and a calibrated electric furnace @1475 I was getting similar varying hardness. 61, 58, 65, 57 etc. I had to grind much further than I thought. Probably .020" before I started getting 65, 65, 64, 65.

Also, if you paid $300 for your fast oil, it probably would have been cheaper to have the Parks shipped. I had it shipped to Wisconsin and it was $125 total.

 

[Jeff the Millwright]

Thank you Kuraki. I will definitely tomorrow try grinding a little deeper and see if I get any better results. You are the second person who has suggested that so maybe that is the secret. I didn’t think it was because with Brine I didn’t have to but maybe they don’t quench in the same way.

Okay, I didn’t pay $300 I keep saying almost $300 and I think it was about $265 and I’m just rounding up because I’m frustrated but there are actually very good reasons why I didn’t have the Parks shipped which I’m sure you not are interested in but it might be therapeutic for me to get it out.

We are cursed in Canada because we are living next to the greatest market in the world. You have no idea how often we can only get things from the United States but we are cursed because getting things across the border can be very frustrating.

Right now the exchange rate makes us lose about 25 to 30% which is frustrating and then it would have been $100 to ship it to Canada which is about 130 Canadian so I already would be up to about $250 Canadian and then there is the cursed brokerage fees that UPS and FedEx extort from us.

Basically your courier acts as your broker and just clears it through customs for you which is probably someone typing at a screen for probably a few minutes and then they pay the sales tax. So you would think it would probably be the sales tax plus a few bucks but no they charge whatever they want and it would probably be another hundred just for the brokerage fees which is highway robbery considering how little they do.

I bought my Evenheat oven from the states and apparently some of the controllers were faulty so they replaced all of them for new customers so I got a free one through UPS. When it was delivered to me UPS wanted $150 brokerage fees. Because it was a free replacement there should have been no charge so I had to contact Evenheat to contact UPS and tell them it was free of charge.

A few days later they re-delivered it without charging me the brokerage fee of $150. On Friday I received a letter from UPS saying I owe them $150 for the brokerage fees for that free part that there should be no brokerage fees on. I’m going to have to call them Monday and try to straighten them out and I’m sure after I do in another month they will send me another bill.

That’s why I didn’t get the Parks shipped to Canada. Excuse me while I get a drink, LOL.