Trying to figure out if Parks #50 will work to quench 80crv2, or if I need to pick up some AAA. After reading through the forums, looks like both have been used with success.
Kevin - Iam curious to know what it does to the steel in quenching too fast... we struggle to get good oils here, you dont actually know how fast it is... some oils we have, that say they are for water quenches, but 3mm 1085 doesnt harden... so it is a bit hit and miss... distortion is one, O1 i did an experiment in water, gained a point as quenched, also warped a 2x1x0.2" piece of O1... but in the fastest oil we get, it was at least 1 hrc point lower than water and straight... any other oil and i get even lower hardness, not much, maybe 64.5 - 65 instead of 65.5-66 as quenched... this after some grain refinement. water was 66.5 and a little above on the test sample, only did it at one temp, not at the variety like the others. so i am using the fastest oil i can get for O1, and 80crv2, but is there anything else one can test or see, that will tell you the oil is too fast? - i don't notice any real brittleness, but that is difficult to quantify.
I also use canola for 80CrV2 but I’d put an * by “successfully” because my observations of success are purely anecdotal. To me, it skates a file and it feels like it’s really hard but I can’t give any numbers or objective data to quantify my success.I've successfully used Canola Oil for 80crv2 steel.
Thanks for the info Kevin this helps.An extra .5 to 1 point HRC at the top end of the range of an alloyed steel from water would be the result of added strain during the direct conductive cooling phase of the quench, strain above and beyond that which is required for the continued martensitic transformation that is occurring in this range. e.g. if you cold hammered the same blade you would also gain a point, regardless of the pearlite to martensite ratio. I have managed to max out HRC in most steels I have worked with simply by zeroing in on the optimum austenization, while using the same oil.
Justin, a whole chart may not be needed to express alloyed = oil (medium speed) , simple carbon = water (fast oil). Anything beyond .25% Cr, or above 1% Mn is probably going to be oil hardening (medium speed). 1075, 1080, 1084, 1095, W-1, W-2 = Fast oil. 5160, 52100, 80CrV2, O-1, L6, 8670M etc. = Medium oil. But this list is requested enough that I believe I will add such a chart to my webpage, when I get back from Blade, if it will help.
Sadly, the internet is more rife with bad knife heat treatment information than ever. I recently had a maker contact me to help him understand which oil to buy since the supplier's literature had the steel to oil matches totally reversed from what they should be. I feel bad for all the folks who had spent money on a medium speed oil for 10XX only to have to spend it again on the correct product.