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[sunshaker]

searching around the internet i discovered Damascus steel. now the process for production is a pain in the ass plus testing for true products produced few but the results was a tough flexible steel that is able to hold its blade and cut though other metals without damage.

Real Damascus or False Damascus (Pattern) Steel people are claiming is Damascus? If the production of the steel involves crucibles and the word Wootz shows up then it is the real stuff, if the process involves welding different steels together than it is the fake pattern stuff.

Cutting through other metals without damage is nothing special, many of the harder metals will cut the softer ones with ease: bronze will cut gold or copper or tin, hardened steel will cut soft (annealed) steel (yes even if the hardened steel is mid-grade 0.6% carbon and the annealed steel is tool grade 0.95% carbon, it just won't do it for very long).

[Tellemurius]

searching around the internet i discovered Damascus steel. now the process for production is a pain in the ass plus testing for true products produced few but the results was a tough flexible steel that is able to hold its blade and cut though other metals without damage.

Real Damascus or False Damascus (Pattern) Steel people are claiming is Damascus? If the production of the steel involves crucibles and the word Wootz shows up then it is the real stuff, if the process involves welding different steels together than it is the fake pattern stuff.

Cutting through other metals without damage is nothing special, many of the harder metals will cut the softer ones with ease: bronze will cut gold or copper or tin, hardened steel will cut soft (annealed) steel (yes even if the hardened steel is mid-grade 0.6% carbon and the annealed steel is tool grade 0.95% carbon, it just won't do it for very long).

well im talking about the real stuff. whet was special about this type of stell that it can cut though other metal AND keep a blade for a long time due to carbides and carbon nanotubes in the steel. now of course the 1400's they didn't know what was nanotubes but they were present.

[Arrkhal]

That's still not a very big deal.  Most armor was made out of much poorer steel than swords, or even of wrought iron.

Carbon nanotubes are found in plain old wood ash and soot and smoke, so it's quite likely they're present in all metals that are heated in close proximity to a charcoal fire.

The vast majority of info about wootz steel, just like katanas, is pure fabrication.  Wootz was a good steel for its time, but accounts were very exaggerated.  Tests have shown that, by modern standards, real wootz is slightly weaker than a modern tool steel (which is an incredible feat given the technology used to make it).

Wootz was also dependent on very specific ores that could only be found around parts of the Indian subcontinent.  When those ores ran out and they had to use normal iron ore, wootz could no longer be made.

It would be good if, in a future version, there can be regional differences like htat, though.  One area's hematite makes a superior steel, another place's marble gives a bonus to statues, etc.

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hardened steel will cut soft (annealed) steel (yes even if the hardened steel is mid-grade 0.6% carbon and the annealed steel is tool grade 0.95% carbon, it just won't do it for very long).

Actually, a hardened 0.60% carbon steel will cut annealed steel of nearly any carbon content (as long as it's not one of those crazy new high-alloy things) for a very long time.  That's what machining often is. (well, okay, most high speed steels are 0.80% carbon or higher, and cobalt alloys work even better, but you get the idea). Yes, the modern fancy ceramic coatings help, but that just means replacing the bit every month instead of every week.

[sunshaker]

hardened steel will cut soft (annealed) steel (yes even if the hardened steel is mid-grade 0.6% carbon and the annealed steel is tool grade 0.95% carbon, it just won't do it for very long).

Actually, a hardened 0.60% carbon steel will cut annealed steel of nearly any carbon content (as long as it's not one of those crazy new high-alloy things) for a very long time.  That's what machining often is. (well, okay, most high speed steels are 0.80% carbon or higher, and cobalt alloys work even better, but you get the idea). Yes, the modern fancy ceramic coatings help, but that just means replacing the bit every month instead of every week.

HHS (High Speed Steel) will cut metal at about 3 times the Speed and Feed as High Carbon Steel (hence the name), Coated Carbide will cut metal about 5 times the Speed and Feed as HHS. At work the Coated Carbide inserts have a designated tool life of 300* pieces (and we hit 300 pieces over 95% of the time, sometimes they can be pushed a bit, maybe 10%), it takes us about 5 hours to do 300 parts. We are a 24/7 factory this means we replace Coated Carbide inserts about 30 times a week per machine. The drills and reamers we use are also Coated Carbide and they have scheduled a tool life of about 1200 holes (again 5 to 6 hours, 4 or 6 holes/part) and again you can push them a bit (about 10%), again this is about 30 times a week per machine. They are sent out for re-sharpening and re-coating, I have no idea how many times they can be re-sharpened (I'll have to ask).

You might have a cutting tool last weeks or a month if you were a low-volume shop, but they don't last that long for our high volume CNC factory.

[Ramirez]

Posted by: Arrkhal
The vast majority of info about wootz steel, just like katanas, is pure fabrication.

While it is true that most of the stories about katanas are exaggerated beyond mortal comparison, they did quite a good job considering the poor quality of their ores. The folding to create fine, alternating layers of high and low carbon steels is both an early example of composite construction (it's too macroscopic to be considered an alloy) and more importantly for this thread, easily doable by dwarves. Just a simple steel + pig iron = 2x folded steel.

For the topic of the ores of wootz steels, would it not be possible to create several different hematites with some of them giving different types of iron (possibly even percentage chances of different irons)? It would let you create different irons with different levels of impurities (low-grade sulphur-rich ores, or high-grade nickel-trace ores, for example).

[sunshaker]

For the topic of the ores of wootz steels, would it not be possible to create several different hematites with some of them giving different types of iron (possibly even percentage chances of different irons)? It would let you create different irons with different levels of impurities (low-grade sulphur-rich ores, or high-grade nickel-trace ores, for example).

Yes you can do that. Either you need to make a bunch of different iron ore types (nickel_iron, sulfur_iron, vanadium_iron, etc) and assign them to different minerals, or you need to make a bunch of different minerals and make a reaction for each of them.

[Arrkhal]

You might have a cutting tool last weeks or a month if you were a low-volume shop, but they don't last that long for our high volume CNC factory.

Only CNC I've experience with was for prototyping only, so very low volume indeed.  Actually, 300 in a month sounds about right.

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While it is true that most of the stories about katanas are exaggerated beyond mortal comparison, they did quite a good job considering the poor quality of their ores. The folding to create fine, alternating layers of high and low carbon steels is both an early example of composite construction (it's too macroscopic to be considered an alloy) and more importantly for this thread, easily doable by dwarves. Just a simple steel + pig iron = 2x folded steel.

Early Japanese metallurgy is quite a bit different from the katana specifically, though.  The Vikings folded different alloys together centuries before the Japanese did, for the same reasons (very low quality ore).

The layers also were not alternating high/low carbon.  Forge-folding will actually equalize carbon content between different alloys.  Other alloying elements are not as mobile as carbon, though, and end up stuck in their layers, which is why folded steel can be etched to show the layers.  But the carbon content of the whole thing will be homogenous, if it's folded into more than about, oh... 30-50 layers?

Also, pig iron has the [BRITTLE] tag for a reason.  Even heated to what would be forging temperature for steel, it will break rather than bend.  Given the carbon content, you'd also end up with very brittle steel, even if successful.

What would actually be a bit closer to the reasoning behind folding metals together, for the Vikings and the Japanese at least, would be 1 iron + 1 steel = 2 very slightly weaker steel.  I.e., if you don't have enough "premium" steel to make an entire blade out of (or to arm an entire army with), you can fold it together with inferior steel to end up with something entirely adequate, but not quite as good as the "premium" metal you started with.  And that actually could be a very valid approach in some games, where steel is just too hard to mass produce (though I hope the dependence on flux is removed).

It would also be possible to accidentally produce a batch of overly-brittle steel, then forge-fold that together with the overly-soft steel you accidentally made last week, and get "regular" steel.  But that's probably well outside the scope of DF.  I would hate having to micromanage what properties each individual bar of steel had!

I think a better way would probably be to just have ores and metal bars have quality mods.  A good furnace operator can increase the quality of the bar over that of the ore by a bit.  And a good quality bar will produce a very slight boost to the quality mod of the resulting item.  Different quality bars can be forge-folded together to produce intermediate quality bars (shifted towards the quality of the better one by skill of the blacksmith).  Add a couple special rules for folding iron and steel together (like that a ☼iron bar☼ is equal to a no-quality steel bar), and you're done.

[Andeerz]

Arrkhal, I don't know if you have done it already as I haven't searched yet, but those kick-ass suggestions regarding regional variations in ore qualities and the like would make an awesome addition to the suggestions forum, and would have my vote if it made it to the eternal suggestions board.  :3  You, sir, are awesome.