heat treating 1095

N

NewbieKnifeGuy

Joined
May 4, 2015
Messages
20
Okay after reading many posts, threads, Web sites I am convinced I know nothing about how to heat treat (harden) 1095 correctly without a temp controlled oven.
I have read Kevin Cashens site about different steel types and it seems like as a novice with hand tools and a simple forge doing 01 Tool steel is not the best cost efficient way to go. So I looked at 1095 and it also says if I overheat past 1500 in the hardening process I get grain growth which makes the blade worse as a knife. How do I with a forge or a small torch and firebrick oven heat treat evenly and correctly at around 1475 for 10 mins as is recommended for even carbon distribution?
Please help I cannot afford even the simplest of heat treat ovens and am not an electrician so I am not going to DIY an oven.
 
I guess I do have a follow up thought. If its not possible to do it really well at home or with my own forge or torch oven. What are my other options sending them off for professional HT or can I go to a college or find someone that would let me come use theirs like through something like the Georgia knife makers guild or the like?
 
I see some HR 1070/1080 on admiralsteel.com, is that like 1084 or should I shop some place else? And I dont have an easy way to anneal it so should I look for CRA 1084?
 
You can heat treat 1095 adequately using your methods. The H/T will not be optimal for the steel, but you can still make a good knife.
You can anneal it in your forge.
 
1070 or 1084 would be better because there is one less thing to go wrong compared to a hypereutectoid steel like 1095. That appears to be the primary basis of Mr. Cashen's advice. His specific advice re O1 is that you are wasting money if you can't get all of those alloying elements into solution with a good soak. You might as well be using 1084.
 
jdm61 has the main reason that experienced makers say, "You can't HT 1095 ( or other steels) in a small forge." The reason isn't that the steel won't harden, it is that all you are doing is getting the equivalent of 1070-1084 in available carbon. On hyper-eutectoid and higher alloy steels it takes time for everything to get properly distributed. The quench also can be a bit trickier and may need faster oils.

Good old 1084, and other hypo-eutectoid steels HT easily with simpler forges and oils.
5160, 1060 -1080, and Aldo's 1084 are all great steels for simple equipment shops.
 
Regardless of your heating source and selected steel (i wouldn't use the torch) you should get a termocouple and stick it in the enclosed area where you austenitize, preferibly a muffle, even a simple one made with a section of an iron pipe.
Overheating hypereutectoids (1095) will put into solution more carbon than it is necessary to reach max hardness and that reinforces the austenite, giving retained austenite in high percentages at the expense of strenght in the finished blade. That concern is even higher than grain growt in terms of performance.
Eutectoids like aisi 1070-1084 won't have this issue and only grain growt should be avoided with the correct temperatures: 1485-1500 °F in this case is the way to go.
1475 °F is correct for aisi 1095... it is less because of the retained austenite concern.

With simple heating sources you won't be able to soak the annealed (we buy annealed steel) steel for the required time at precise temperature, so do a normalization and a grain refinement in steps before the final austenitization....that will pre-set the steel for a very quick aust., almost no soak required and less distortion to be expected in the quench. Also don't be afraid to agitate during the quench in a stabbing/slicing direction.

Hope it helps

Stefano
 
Last edited:
You must log in or register to reply here.
Back
Top