strategy9
Gold Member
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- Apr 27, 2015
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I heard some refer N690 as VG10 equivalents, which should be above BD1 in edge retention, assuming all by Spyderco standard HT. BD1 having slightly lower Carbon than the other two, but higher than AUS8. I like it (BD1) too.
Can steel experts confirm this?
VG10 and N690 are almost identical in their composition; with the main differences are n690 having tighter tolerances and consistency, with a significantly higher chromium content, and VG10 having a wider tolerance in the alloying elements due large in part to the manufacturing processes.
Rather then a B = amount, it's a "between A and C"
This leaves room for more variance in vg10 from batch to batch, depending on what marks they hit within the thresholds.
Assuming proper heat treatment for both, a vg10 knife that hit all the high marks of carbon, chromium, vanadium, and molybednum would theoretically outperform an identical vg10 knife that was made hitting all the low marks. Not that it would be a "bad" steel all of a sudden, provided a proper HT it would still be good, but it would be "not quite as good" as another knife with the "same" steel but a more ideal composition
Keep in mind, small differences can make noticeable changes when alloying metals, so -0.1% carbon, -1% chromium, -0.2% vanadium, molybednum, and cobalt, in essence is a different alloy then one having all of those elements present in the higher amounts, even though both are within the vg10 threshold. It's not uncommon, the same issues apply for many alloyed steels, especially those which aren't using modern particle vacuum technologies; aus, cr-mov, 440, d2, etc... billet steel is just not as exact of a science when compared to particle steels which are more precise and consitent, though some top makers are still really good at keeping tight tolerances.
BD1 is also "similar", with tight tolerances it has slightly less carbon then low end vg10, slightly more chromium, 1/3 the moly, and no cobalt added, but a vaccuum melted steel creates a clean even distrubution...

