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Old 03-21-2016, 07:39 AM
Kevin R. Cashen Kevin R. Cashen is offline
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Join Date: Feb 2003
Location: Hubbardston, MI
Posts: 324
Here we encounter the frustrating limitations of ?flex? tests in evaluating heat treatment. The only part of gradual loading and deformation, such as over a rod, that heat treatment effects is what occurs beyond the elastic limits (proportional range). Thus one must either bend or chip the edge to see the heat treatment effects, and before that all of the load level to deformation observed is determined entirely by the grind, not the heat treatment, and yet the brass rod continues to be a curious standard. In this case what makes the information gleaned come into any useable focus is coupling it with the file check as well. The file doesn?t directly relate to penetration hardness but it at least measures a form of hardness.

1084 has one of the highest levels of Mn in the 10XX series and thus has some of the deeper hardening levels- although it is still a shallow hardening steel, I still always scratch my head when it is described as a deep hardening steel. On the other hand 1095 has some of the lowest Mn levels and thus it?s about the shallowest hardening steel we regularly encounter; so much so that I use it for all of my quench evaluation studies when consulted for quenchant analysis. The only oil, so far, that I have been able to achieve full hardening in 1095 much greater than 3/16? is Parks #50, with Houghtoquench ?K? coming in a close second.

Another clue I got from the situation described is the hesitation to buy 5 gallons of quenchant- not a problem there but it indicated that less than 5 gallons could be being used currently, to which I begin to ask what the quantity is? If it is around 2 gallons or less, depending on the shape of the container, you may not have enough volume for proper thermal extraction. Also, having room to be able to agitate, or circulate the oil is very important, particularly with 1095; just holding it still in the oil will give you all kinds of mixed results.
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