[Nat Lamb]

<--- not a swordsmith or metallurgist.
My (limited) understanding is that modern steels, provided you use one appropriate for the job, not one optimised for some other task, are vastly superior to the majority of pre industrial revolution steels for making a blade.

steels like 5160 are, if properly heat treated, incredibly tough, and have a number of properties that make them ideal for making a sword. Is it better than the steel used in the absolute finest blades made historically? I don't know, maybe not. However, it is a very simple thing for even an amateur hobbyist to get their hands on steel that is almost as good as the best ever used, and of uniform and predictable quality. Compared to the steel used for an *average* sword historically, I would be willing to bet that even what you pick up as scrap at an auto yard will be better (though much more reliant on the skill of the person doing the heat treating).

again, I am not a smith or materials scientist, so salt this opinion according to taste.

[Timo Nieminen]

With wootz, quench and you get hard and brittle. Cool slowly (i.e., air cool), and you get soft (about HRC30) but with good edge retention due to carbides and still potentially brittle. I don't know if the modern market will like swords of HRC30, even with good edge retention. I've heard people tell stories of the time they dropped and antique wootz sword and the blade snapped. The modern market certainly won't like that kind of thing.

We can do better than the average wootz sword with the best forging and heat treatment. (The forging matters - need to be in the right temperature range, and work for long enough to break up carbides into small grains.) We have thermometers so that we can repeat what we do, and microscopes so we can see the effect on the microstructure of the steel.

But the usual modern sword steels are more forgiving - easy to get the heat treatment good enough - and will give a tough hard blade when done right. 5160 or 1070 or 1095 or similar.

Wootz would be like 440C stainless steel. You can make a good hard and sufficiently tough sword, but if the heat treatment isn't spot-on, it will be too brittle.

I have a kitchen knife with carbon content of 1.3%, which is in the wootz range. Very hard blade. Wouldn't trust that steel and heat treat for a sword - too brittle. A kitchen knife is cut with often. For professionals, all day. How often does a sword cut? Toughness and reasonable hardness and edge retention is better than brittleness and super-hardness and super edge retention. (Opinion, of course, so YMMV. But similar things were said by Europeans about wootz swords in the 19th century.)

[Greg Thomas Obach]

wootz is an ultrahigh carbon steel ! after .8% carbon, the rest goes into cementite ... so you have alot of carbide but .. its where you put this carbide that makes all the difference in the world.

properly forged and heat treated, wootz is not brittle ! why use it as a sword steel if it was brittle ???? In India and Persia, there are alot of examples of pattern welded swords at the same time as wootz, and yet they prefered wootz steel ! Ask yourself " Why ?"

however, if you have alot of grain boundary carbide, this can be brittle .. but thats different

look at the micrographs of wootz ... a macro view of wootz looks like big carbides but when you look closely these are many small globular shaped carbide particles

wootz by very nature has to be forged at a much cooler temp.... therefore you almost alway end up with a very small grain structure

it was a very good steel back in the old days

today we have much better alloys...

do we need the better alloys ? what Rc is skin and flesh... not very high ...

[Dan Howard]

Looks like we finally have a non-destructive way to analyse the metallurgical composition of swords.
http://www.gizmag.com/stfc-indian-shamsheer-sword/36105/

[Rim Andries]

[Lafayette C Curtis]

This is what the Japanese version of bloomery iron/steel (tamahagane) looks like:

http://www.ksky.ne.jp/~sumie99/others1.html

While this is a good overview of the differential hardening process by clay-quenching: http://www.tameshigiri.ca/2014/09/14/putting-...quenching/

I'm not even going into European swords since there's a huge variety of heat treatment methods with historical evidence to back them up, and even more that modern smiths and swordmakers have created/improvised on their own. And each one takes a lifetime to master.