S90V compared to REX45

[Rinzler]

How does S90V compare to Rex45 aside from corrosion resistance?

[Naperville]

EDITED

The most recent ad that I saw for a Spyderco Native Chief was that the knife had an HRC of 59-61. I do not know if that is correct based on the HRC numbers that I've seen earlier. I'm guessing it has an HRC between 64.5 and 67.0. Rex45 could be the highest HRC from Spyderco except for Maxamet.

HRC OF VARIOUS STEELS PRODUCED BY SPYDERCO
(Spyderco Forums) ZrowsN1s » Last edited by ZrowsN1s on Thu Dec 19, 2019 12:20 pm, edited 38 times in total.

viewtopic.php?f=2&t=83847
viewtopic.php?f=2&t=73097

REX45 Military - (66.3 - 67) HRC
REX45 Paramilitary 2 - (65 - 66.7) HRC
REX45 Para 3 - 64.7 HRC

S90V Military - 60 HRC
S90V Manix 2 LW - 59.9 HRC
S90V Mule - 59.2 HRC

[Vaugith]

Both are very wear resistant, but by different mechanisms. Rex45 has a high hardness matrix while s90v has a very high vanadium carbide count (the hardest type) in an average hardness matrix. In my experience rex45 will suffer less edge damage against hard materials like copper, hard woods, brass, but I couldn't tell you which would win in head to head slicing edge retention. Both would have very good numbers.

[kobold]

o.O Very different.

[JMM]

S90V is a stainless steel and will not rust as easily as Rex45 which is a tool steel, I personally keep a thin coat of mineral oil (it's food safe, cheap, and easy to find) on my tool steel blades (and some of my stainless like xhp) and I have zero problems living where it's wet or humid or both year round... They're both great, but quite different steels IMO. There are lots of folks around these parts that are way smarter than me about this stuff so I'll leave it at that. :)

[Matus]

I can only assume that pushing the S90V any higher in hardness would yield unacceptably low toughness. And since already at 60 HRC the edge retention is really very good, there was probably little need to push it higher and risk issues with chipping. I am only guessing though.

[ugaarguy]

Per Crucible's data sheets, Rex 45 at 65 HRC is slightly tougher (higher impact resistance) than S90V is at 58 HRC. The data sheet also indicate that S90V has 19% higher impact resistance than 440C with both at the same 58 HRC.
http://www.crucible.com/PDFs/DataSheets ... 202010.pdf
http://www.crucible.com/PDFs/DataSheets ... v12010.pdf

[Rinzler]

I’m reading a bit on S90V and have seen many comments on the difficulty to sharpen it. I already have a few rex45 knives and I find that it sharpens just fine. I’m wondering if s90v is as bad as I’m reading...

[Donut]

I know I had a messed up bevel on my S90V mule and it takes quite a bit of time to reprofile. I remember stopping a few times and saying... "man, this is taking too long to reprofile, my hand is getting tired."

[p_atrick]

I’m wondering if s90v is as bad as I’m reading...

I always wonder about describing a steel as "hard" to sharpen. I don't own anything in S90V, but I would bet the steel's difficulty is really a combination of my mediocre technique and meager stones. One day I'll probably own a "difficult" steel if only to force me to up my game.

[TomAiello]

Rex45 has better edge holding, s90v has better corrosion resistance, I'd say Rex has a slight toughness advantage but not a huge one in my EDC use.

If I had to use the same EDC knife forever, I'd rather have s90v. If I had a rotation of EDC knives, I'd rather have Rex45 in the rotation with s90v, assuming I could have some other stainless in the rotation as well.

I find them about the same to sharpen. In general I think that the complaints about sharpening generally come from people who need to spend some time on their sharpening, rather than complaining about the steel.