Recommendation? 52100 HT Recommendations - (2023 edition)

[Steelhog]

Hey all - I would like to do some work with 52100 and this steel for whatever seems to have a good deal of variation in temps/times and quenchant recommended. More than most of the other carbon steels I have seen. I have seen temps ranging from 1465 to 1615 all from reputable sources and past threads. I have also seen med speed and high speed oils recommended saying the other may work or wont work. 52100 also has some mystification around it for what ever reason.

Really just trying to determine the most straight froward HT practice to get good performance and consistent results. I am inclined to just follow KFSN data as that is my standard practice but this steel seems to have some industry variation and even he has a disclaimer that those numbers worked for him but may not be the best.

Please help me out on this one. Thanks all!

 

[Seedy Lot]

Straight from Larrin's KSN article.

1700°F for 20 minutes, air cool

1460° for 30 minutes, air cool

1460° for 30 minutes, cool at 670°F/h to 1260°F, air cool

By following these steps I had the best hardening response from a few different attmepts.

 

[Stacy E. Apelt - Bladesmith]

After the above annealing and grain refinement heat to 1475-1500°F and hold for 15 minutes. Quench in Parks #50 or equivalent and let cool to room temp. Place in the freezer for 4 hours if you want to (I don't) and ten temper twice at 400°F.

 

[Seedy Lot]

For the last batch of 52100 I heat treated, after the Larrin steps I austentized at 1525F for 15 minutes and quenched in parks 50.

I started tempering closer to 300F for 63 Rc for a few blanks and then tempered the rest of the blanks again at 50F degrees hotter to get 61 Rc.

I was using a steel from a supplier here one the forum that says no extra steps are needed for heat treating but with the Larrin pre steps I reached 2 Rc harder.

I do find the pre steps to be a pain but if I use 52100 again I will follow them as the results were worth the extra effort.

 

[Steelhog]

For the last batch of 52100 I heat treated, after the Larrin steps I austentized at 1525F for 15 minutes and quenched in parks 50.

I started tempering closer to 300F for 63 Rc for a few blanks and then tempered the rest of the blanks again at 50F degrees hotter to get 61 Rc.

I was using a steel from a supplier here one the forum that says no extra steps are needed for heat treating but with the Larrin pre steps I reached 2 Rc harder.

I do find the pre steps to be a pain but if I use 52100 again I will follow them as the results were worth the extra effort.

Perfect - thank you.