Sciencemadness Discussion Board

Ancient metallurgy

D4RR3N - 10-9-2015 at 15:19

I have always been interested in ancient metallurgy, largely due to the strange ingredients they would often mix together for example meteorite Iron and copper (Tibet), Copper, gold,silver,Iron and tin (India)

In India there were alloys made by adding 3 (triloha), 5 (panchaloha) and 8 metals (Ashtadhatu) together. We today would never dream of making such a complex alloy of 8 metals or of adding noble metals such as gold to iron alloys.

Sometimes they would mix animal products, plant material and minerals with metals. Brass in the old days was made by heating copper with powdered calamine as zinc was an unknown metal.

Plato talks about the metal Orichalcum and said the temple of Poseidon in Atlantis flashed red with the light of Orichalcum. Recently ancient metal ingots were discovered and it was claimed that they were Orichalcum however Plato said it was a red metal and what they found was yellow brass.
http://www.dailymail.co.uk/sciencetech/article-2901795/Does-...

Corinthian bronze would not tarnish like common bronze.

wootz steel is a mystery.

Hepatizon was a liver colored alloy.

In Tibet there are still metal smiths who guard secret formulas for alloys written in ancient Sanskrit.

Some Indian text talk about imparting a golden or iridescent colour to alloys which resists rusting.

I would like to discuss here materials which would have been available to the ancients that they may have used in producing weird mixtures that todays chemists perhaps would not attempt due to the odd nature of the ingredients.

I was thinking plant matter would be burned up however the ash of some plants is high in alkali metals, silica etc

Crushed animal products such a bone meal, high in phosphorous

Crushed and powdered minerals, gems, rocks etc

I would like to start by asking the question what would be the result of bone meal added to molten bronze ?



[Edited on 10-9-2015 by D4RR3N]

Bert - 10-9-2015 at 18:01
Quote:

wootz steel is a mystery.


Um, no. Mystery solved, you just have to start with the correct batch of ore to get the recipe to work. Apparently minor contaminant (serendipitous alloying?) elements make or break the process, not the phase of the moon.

Some careful analytical work involving samples from collectors willing to sacrifice a few slivers from some VERY special antique blades, and research into archaeology/sociology/trade route and military/political history pretty much solved that one
Quote:

I was thinking plant matter would be burned up however the ash of some plants is high in alkali metals, silica etc


Dead on. Like adding to sword steel smelts charcoal of a fungus that bio concentrates a seemingly meaningless, tiny yet crucial amount of Vanadium.

Yes, I love this stuff too.

Old technologies may not be sexy, but they WORKED. Stupid illiterate pre industrial era peasants DIED. Smart ones lived, and some had a very keen aptitude for observation of their processes, regardless of lacking modern analytical equipment and theory-

I've got hard copies of books such as:

The Pirotechnia of Vannoccio Biringuccio

De re Metallica by Georgius Agricola

The Encyclopedia of Denis Diderot

The Great Art of Artillery of Kazimierz Siemienowicz

And a few others.










Quote:

Agricola does not reject the idea of alchemy, but notes that alchemical writings are obscure and that we do not read of any of the masters who became rich. He then describes fraudulent alchemists, who deserve the death penalty.


[Edited on 11-9-2015 by Bert]

careysub - 10-9-2015 at 20:17

Quote: Originally posted by Bert  

Quote:

wootz steel is a mystery.


Um, no. Mystery solved, you just have to start with the correct batch of ore to get the recipe to work. Apparently minor contaminant (serendipitous alloying?) elements make or break the process, not the phase of the moon.

Some careful analytical work involving samples from collectors willing to sacrifice a few slivers from some VERY special antique blades, and research into archaeology/sociology/trade route and military/political history pretty much solved that one


Here is the reference:
http://www.tms.org/pubs/journals/jom/9809/verhoeven-9809.htm...

violet sin - 10-9-2015 at 23:05

thanks Bert- "Dead on. Like adding to sword steel smelts charcoal of a fungus that bio concentrates a seemingly meaningless, tiny yet crucial amount of Vanadium."

I searched that idea for a sec, and found a bunch of fun papers to read some time. some were about bioremediation, but I found a few nice ones that were more of studies on found strains of fungus and their contamination levels. bunch of free PDF's available. if I get a chance to read a few that seem good, I'll link them.

D4RR3N - 11-9-2015 at 01:56

Bert,

I would suggest trying to find a photo of modern wootz steel because though the theory is there (or part of it) I have not seen any good modern wootz steel. I have seen blades made which had partial patina but not anything like ancient blades.

Last I read is that wootz steel was found to contain carbon nano tubes and some are working on the idea that a fibrous organic source (not charcoal powder) must be added to the melt to form the tubes in addition to some plant chemistry.

http://scienceblogs.com/notrocketscience/2008/09/27/carbon-n...



[Edited on 11-9-2015 by D4RR3N]

D4RR3N - 11-9-2015 at 02:00

The question about bone meal added to hot bronze, would it harden the bronze allowing you to make better swords?

careysub - 11-9-2015 at 06:47

Quote: Originally posted by D4RR3N  
Bert,

I would suggest trying to find a photo of modern wootz steel because though the theory is there (or part of it) I have not seen any good modern wootz steel. I have seen blades made which had partial patina but not anything like ancient blades.

Last I read is that wootz steel was found to contain carbon nano tubes and some are working on the idea that a fibrous organic source (not charcoal powder) must be added to the melt to form the tubes in addition to some plant chemistry.

http://scienceblogs.com/notrocketscience/2008/09/27/carbon-n...


One thing missing from the impressive study of Damascus blades I cited above, is that don't discuss attempts to replicate the whole process that they propose. it is all analysis and deduction, no replication - only when we can exactly duplicate the manufacture then we can say we have fully solved the problem.

One peculiarity about the paper that I cannot explain is its contention that a high phosphorous content of the steel rendered it "hot short" (unworkable due to crumbliness at red heat), and they discuss a proposed process to combat this.

From my knowledge (and according to my standard references) phosphorous renders iron "cold short" not "hot short" (which is due to sulfur).

D4RR3N - 11-9-2015 at 08:21

I have purchased a few books on ancient Indian metallurgy and a reoccurring theme is that before the Iron was melted it was "purified" by boiling it in large quantity's of plant derived liquids for long periods of time. This plant derived liquid when reduced and fired at high temperatures with the Iron might actually be the source of the carbon naotubes.

[Edited on 11-9-2015 by D4RR3N]

Thraxx - 11-12-2016 at 11:32

The Wootz is iron with Vanad carbid,in 19 century in London expo was one Russian with wootz,after was it forgotten and then in Canada was one smith which was known and now the group of enthusiast found this secret.It seems that it have properties of excellent steel,but not better than other excellent steels.Surface look like grey cubes.

unionised - 11-12-2016 at 14:24

Quote: Originally posted by D4RR3N  
We today would never dream of making such a complex alloy of 8 metals or of adding noble metals such as gold to iron alloys

[Edited on 10-9-2015 by D4RR3N]

Guess again: we get close
https://en.wikipedia.org/wiki/Eglin_steel
And we add gallium to iron
https://en.wikipedia.org/wiki/Galfenol
and aluminium with gold
https://en.wikipedia.org/wiki/Colored_gold#Purple_gold

AJKOER - 20-12-2016 at 04:35

Maintaining the luster on alloys may be a matter of the local environment. Add sea salt spray (a good electrolyte) and your inert alloy may become electrochemically altered. Research metal-air batteries, metal-sulfur batteries, even a galvanic cell from an alloy (see, for example, https://www.google.com/patents/US4264362 ).

One would hope that the science of keeping your weapon sharp (at its peak) has long been solved. However, the report of dissolving new fast Aluminum warships (see https://www.wired.com/2011/06/shipbuilder-blames-navy-as-bra... ) suffering aggressive corrosion at the interface of iron water jets with the aluminum hull in sea water (and even worst in polluted/acidic waters) suggests otherwise.

I recently observed during my travels in Florida, a hot humid southern state, that the local copper pennies seemed to be unusually corroded. While my observations are not based on a thoroughly designed scientific study, the local conditions, which apparently include heat, sunlight, high humidity, a long coast line and sulfur rich fresh water, do suggest a potentially active environment for galvanic corrosion.

[Edited on 20-12-2016 by AJKOER]