Which is better quality, T10 tool steel or 9260 spring steel

QUESTION

Which one is better the T10 or the 9260 spring steel? Which can cut better, which can bend and which is harder? Which is all around better for swords?

ANSWER

I get asked this question a fair bit, and having torture tested swords made from both of these steels - and my answer will have to be a bit of a long winded one as 'better' is such a hard term to define (because it depends on what targets you intend to use the sword on!)..

T10 is a harder steel than 9260. Indeed, it is very similar to 1095 (.95% carbon) carbon steel, and 9260 is similar to 1060 (.6% carbon) - and as you may know a sword with a higher carbon content is (all other things being equal) harder than one with a lower carbon content. The main difference between these two steels and the 'plain Jane' vaninlla carbon steels is the addition of various alloying agents (Tungsten in the case of T10 and Silicon for the 9260).

In my experience, I've found that 9260 works better when it is monotempered (i.e. is the same hardness of steel all the way through) while T10 comes into its own when it is clay tempered and differentially hardened in the traditional way.

When monotempered, the extremely flexible qualities of 9260 Spring Steel come into their own as demonstrated in the following video.



When you differentially harden it (like with the Cheness Kaze Katana) you lose this quality, but still end up with a sword that is slightly more resiliant than most other steels (as a rule, differentially hardened swords with a real hamon cannot flex sideways like a monotempered sword. Well, they can - but they don't flex back if you know what I mean)!!

T10 on the other hand is not as flexible or as durable as 9260 when it is monotempered, but in my experience when it is differentially hardened it has a harder and sharper edge, and seems to really take a nice hamon..

And as you can see from the video below, is more than tough enough for everyday cutting practices.



So in conclusion, 9260 blades are best when monotempered - and are durable, flexible and great for a beginner who may accidently botch a cut or two.

T10 blades seem to be best when differentially hardened - taking on a very attractive and traditional hamon, and are more than strong enough for normal cutting.

Bear in mind of course that there is no such thing as a miracle steel, a well made 1060 carbon steel sword can, for all intents and purposes, do pretty much anything a 9260 blade can.

What matters most is WHO made it, how it was forged and tempered and other very important considerations that are often forgotten such as the quality and structural integrity of the fittings, etc.

For more information on steel types (including additional information on 9260 and T10 steel, as well as many others) see this article: Common Sword Steels 101 on our sister site.

I know it is not exactly a 'straight' answer - but as with many sword questions, they are often a bit more complicated than they first appear. ;-)

Hope this helps anyway.

- Paul