D2 and S90V are industry standards when it comes to high-end knives. Both steels are used by the biggest names out there (brands like SOG, Benchmade, Gerber, Buck, and Kershaw all use D2 or S90V or both). With these steels being used by so many brands it would only make sense to compare the two.
Here is the short answer:
In most cases, S90V is better than D2. S90V is way more corrosion resistant, keeps its edge longer, and has slightly better strength. D2 is cheaper and has relatively the same toughness, so if you don’t want to spend a lot of money then go with D2.
With the short answer out of the way, we can look at when you would want D2 over S90V and vice versa.
D2
D2 is a high-quality budget steel. D2 is primarily used in tools because of its extreme wear resistance and durability. But D2 is not just for tools, many companies use it because of its wear resistance and toughness.
There are some downsides to D2. D2 is not very corrosion-resistant. It does not take much to rust a D2 knife. So if you are going to be in an environment where there is a lot of rain and humidity, you may want to steer clear of D2.
However, D2 steel, like any steel, can vary depending on where it is made, who made it, its blade angle, and its heat treat.
Here is what D2 is made of:
- Carbon: 1.5%
- Chromium: 12.00%
- Vanadium: 0.90%
- Molybdenum: 0.80%
- Magnesium: 0.45%
- Silicon: 0.40%
- Sulfur: 0.02%
Carbon increases edge retention and steel strength. Chromium helps with a steel’s corrosion resistance (D2 has a high chromium content but this is misleading as it is not very corrosion resistant). Vanadium increases wear resistance. Molybdenum will increase the chances of getting a better heat treat. Magnesium, silicon, and sulfur increase steel strength much like carbon.
S90V
S90V is a higher price steel but it is a higher quality steel. S90V is a very durable, high wear resistance, and very corrosion resistant steel that makes it a great steel for almost all applications.
Like any steel, S90V has its downsides. Because S90V holds its edge so well, it can be hard to work with and sharpen. The other downside is that S90V is expensive and can be very costly to buy.
And S90V can still have the same variation on everything from corrosion resistance to durability depending on where it’s made and who it’s made by.
Here are the materials in S90V:
- 2.30% Carbon
- 14.00% Chromium,
- 9.00% Vanadium
- 1.00% Molybdenum
Which one is better?
Now that we have looked at each steel we can compare the two to see which one is better and why.
If you compare the different steels by looking at the materials, S90V is better. S90V has more carbon meaning it is more substantial. It has more chromium meaning it is better with corrosion resistance. And it has more vanadium so it has better wear resistance.
In the real world, S90V is also better. As we know from the short answer, it is better at almost everything when compared to D2. The only reason you would want D2 over S90V is if you were looking for a more budget option.
So in pretty much all ways, S90V is a better steel.
Our favorite knives in each steel
Now that you know which steel is better, we can look at our favorite knives in each steel.
SOG Aegis At (D2)
The SOG Aegis AT is an EDC (EveryDay Carry) knife that is great at its job. It has GRN handle scales and a 3-inch D2 blade. The Aegis also features SOG’s “AT-XR” blade lock and spine safety.
You can check out this knife here (link to Amazon)
Benchmade Altitude (S90V)
The Altitude is a lightweight hunting knife made for the most serious hunters. It weighs only 1.67 ounces, making it great for backpacking trips. And it has a G-10 micro scale for extra grip in wet conditions.
You can check out this knife here (link to Amazon)
SOG Terminus XR (D2)
The Terminus is an ideal EDC knife. It’s small enough to be carried everywhere, but big enough to fit nicely in the hands of most users. It has a deep carry pocket clip for ultimate concealment while still being comfortable. If I were to have one EDC knife for the rest of my life, this would be it.
You can check out this knife here (link to Amazon)
Conclusion
While S90V is better than D2, unless you will be beating your knife up day and night, you won’t notice a huge difference. As long as you are fine with having to sharpen your knife now and then and having to treat it from corrosion, you might as well go with D2.