[LT] No-steel-pocalypse! Lifespan of iron & steel equipment?

[Sword-dancer]

Originally Posted by Seneschal

The original recipients of the boon were a tribal bronze-age culture with mostly oral traditions. .

so no druids, Brahmins, Bards/Skalds , No linear B script, Cuneiform or else?

[malloyd]

Originally Posted by Seneschal

That boon is due to end in a month, and I was wondering just what kind of chaos would ensue. Assume that the biggest portion of their economy is based on metalworking. How soon would steel need maintenance which could not be done anymore? What components of infrastructure used iron or steel at TL4, and would now become irreplaceable? What adjustments would need to occur if an entire culture would have to switch to softer metals overnight?

Properly cared for steel tools that don't see a lot of use can last a century - half of my hand tools belonged to my father and are 50 or 60 years old - so the crisis isn't immediate.

Heavily used stuff will wear out faster, but most craftsmen who are well equipped now will still have usable gear in a decade or more. Your economy isn't going to crash overnight, or even this year, though the long term outlook is pretty poor. Nobody *new* can enter a profession that requires steel tools - your economy can't expand and is going to start contracting with a half life of decades in those industries, which is most of them.

The first really major crisis is probably plows - TL4 food surpluses are not large, so every farmer whose efficiency drops because his plow breaks mean somebody somewhere starves, and plowshares are worked pretty hard. Next year is probably OK, particularly if the planting season is already over, but if you don't solve this one pretty fast the year after that will be a hard year and half your population is going to be dead in a decade.

In some ways you are in luck though, because other TL4 industries, most significantly glassmaking, require high temperatures too, so you don't have to invent everything *completely* from scratch. Depending on how this boon worked you may need to invent a lot though. Real ironworking before about mid TL5 actually involved relatively little melting - because cast iron is frankly a fairly lousy material. If this boon got around that, and one assumes it did or it wasn't really all that valuable, these guys may have no ironworking techniques at all. Even if not prices are going to go up (if for no other reason than you need more fuel), but if you are lucky your civilization may just be looking at half century long depression rather than total doom.

[DanHoward]

As has been said, most iron and steel products will last for centuries if they are well maintained. Those that wear out can be replaced with bronze with no trouble so long as copper and tin are available. There were very few TL4 items that could only be made from steel. The only short term effect on society would be an increase in the cost of iron/steel items - depending on how much material is in the production pipelines. People would very quickly learn to look after what they have - recycling and repurposing would be even more prolific. As usual with situations like this, those who will be most affected will be the poorest members of society while the rich will barely notice.

There will be almost no long term effect. Bronze can be used as a short term replacement and TL1 furnaces have no trouble making iron and steel - it just takes longer and is less efficient. It won't take long at all to develop TL4 furnaces if the rest of society is TL4.

[Agemegos]

Originally Posted by malloyd

In some ways you are in luck though, because other TL4 industries, most significantly glassmaking, require high temperatures too, so you don't have to invent everything *completely* from scratch.

One such is smelting iron. A lower melting point for iron is not itself relevant to needing high-temperatures and charcoal or coke to produce iron in the first place: the reduction of iron from its oxides is not a process of melting, and indeed traditionally took place without melting until the Industrial Revolution.

Depending on how this boon worked you may need to invent a lot though. Real ironworking before about mid TL5 actually involved relatively little melting - because cast iron is frankly a fairly lousy material. If this boon got around that, and one assumes it did or it wasn't really all that valuable, these guys may have no ironworking techniques at all.

It might be worth reminding the folk reading that the melting point of pure iron is 1538 C (2800 Fahrenheit), and wasn't achieved in industry until about 1850. The "cast iron" made before then (as early as the fourth century BC, in China, a thousand year later in Europe) was not jusy iron that had been melted and cast, but a mixture (solid solution) of iron with iron carbide. That has a much lower melting point and very different mechanical properties. The material in this fantasy campaign won't be cast iron even though it has been cast, it will be wrought iron even though it wasn't wrought.

One thing worth noting is that it's much easier to get fine detail in castings of material with a low melting point; you can pre-heat the mould and then the narrow channels and grooves don't get blocked with menicuses of frozen melt, which is what happens when molten iron cools rapidly in a mould because it's not practical to heat moulds to 1538 C. With a gift that allows melting iron at only a few hundred Celsius these people are going to produce iron artifacts that look quite unlike the forged iron and steel objects we are used to. Also, iron objects are going to be cheaper for them than they were for our ancestors because they will save not only a lot of fuel but also a great deal of labour workibf bloomery iron into bars, forging out the slag, and tediously shaping and welding iron pieces with the hammer and anvil.

Another point is that they might not have steel. Their bloomeries might not produce iron with significant carbide in it with the melting point of iron so much below that of iron carbide. Their workpieces won't carburise in the furnace, because they won't be forged. And finally, their iron melts below the Austenite-Marstenite transition temperature, so they wouldn't be able to quench their steel if they did make any.

Originally Posted by PseudoFenton

So in the last thousand years, noone has developed better furnaces? Despite knowing what hotter temperatures could do when working iron?

The higher temperatures won't do those things if the iron melts at 327 C. You need steel to be solid at about 550 C or above for to heat-treat it.

Moreover, these people would be working steel in the forge because they can much more easily and accurately cast it.

[DanHoward]

Originally Posted by Agemegos

One such is smelting iron. A lower melting point for iron is not itself relevant to needing high-temperatures and charcoal or coke to produce iron in the first place: the reduction of iron from its oxides is not a process of melting, and indeed traditionally took place without melting until the Industrial Revolution.

It might be worth reminding the folk reading that the melting point of pure iron is 1538 C (2800 Fahrenheit), and wasn't achieved in industry until about 1850. The "cast iron" made before then (as early as the fourth century BC, in China, a thousand year later in Europe) was not jusy iron that had been melted and cast, but a mixture (solid solution) of iron with iron carbide. That has a much lower melting point and very different mechanical properties. The material in this fantasy campaign won't be cast iron even though it has been cast, it will be wrought iron even though it wasn't wrought.

One thing worth noting is that it's much easier to get fine detail in castings of material with a low melting point; you can pre-heat the mould and then the narrow channels and grooves don't get blocked with menicuses of frozen melt, which is what happens when molten iron cools rapidly in a mould because it's not practical to heat moulds to 1538 C. With a gift that allows melting iron at only a few hundred Celsius these people are going to produce iron artifacts that look quite unlike the forged iron and steel objects we are used to. Also, iron objects are going to be cheaper for them than they were for our ancestors because they will save not only a lot of fuel but also a great deal of labour workibf bloomery iron into bars, forging out the slag, and tediously shaping and welding iron pieces with the hammer and anvil.

Another point is that they might not have steel. Their bloomeries might not produce iron with significant carbide in it with the melting point of iron so much below that of iron carbide. Their workpieces won't carburise in the furnace, because they won't be forged. And finally, their iron melts below the Austenite-Marstenite transition temperature, so they wouldn't be able to quench their steel if they did make any.

The higher temperatures won't do those things if the iron melts at 327 C. You need steel to be solid at about 550 C or above for to heat-treat it.

Moreover, these people would be working steel in the forge because they can much more easily and accurately cast it.

In this situation, all that will happen is that you will have two different groups of craftsman. The first group makes iron products using the lower melting point provided by the boon while the second group make steel products in the same way that we have always done historically. If this is the case then there will be almost no interruption to society at all except that craftsman will move from the first group to the second and start using these techniques to work with low carbon iron as well.

[Agemegos]

That would involve trade between the culture that got the boon and other cultures that could still make steel, right?

[DanHoward]

Originally Posted by Agemegos

That would involve trade between the culture that got the boon and other cultures that could still make steel, right?

Only if that entire culture was incapable of working with steel. Was the boon given to every person or just a select few? How hard would it be to encourage steel workers from another culture to come work for you? Why haven't these people already been conquered by someone who could outfit his army in steel weapons and armour?

[Seneschal]

Originally Posted by Agemegos

It might be worth reminding the folk reading that the melting point of pure iron is 1538 C (2800 Fahrenheit), and wasn't achieved in industry until about 1850. The "cast iron" made before then (as early as the fourth century BC, in China, a thousand year later in Europe) was not jusy iron that had been melted and cast, but a mixture (solid solution) of iron with iron carbide. That has a much lower melting point and very different mechanical properties. The material in this fantasy campaign won't be cast iron even though it has been cast, it will be wrought iron even though it wasn't wrought.

So, if I understood correctly, under these made-up rules, the iron would be easily cast, but would have the properties of relatively pure iron? So, weapons and armor made from such a material would be softer than steel, but not as brittle?

Originally Posted by Agemegos

One thing worth noting is that it's much easier to get fine detail in castings of material with a low melting point; you can pre-heat the mould and then the narrow channels and grooves don't get blocked with menicuses of frozen melt, which is what happens when molten iron cools rapidly in a mould because it's not practical to heat moulds to 1538 C. With a gift that allows melting iron at only a few hundred Celsius these people are going to produce iron artifacts that look quite unlike the forged iron and steel objects we are used to. Also, iron objects are going to be cheaper for them than they were for our ancestors because they will save not only a lot of fuel but also a great deal of labour workibf bloomery iron into bars, forging out the slag, and tediously shaping and welding iron pieces with the hammer and anvil.

By "quite unlike" do you mean they would more easily be made elaborate? That fits neatly with the image I presented to the players so far, where the fashion was ostentatious to the point of tastelessness, e.g. impractical full-body metalwork as street-clothes. I'm just not quite sure what decorative techniques they'd have access to (boon aside, they're technologically TL2, possibly 3).

Originally Posted by Agemegos

Another point is that they might not have steel. Their bloomeries might not produce iron with significant carbide in it with the melting point of iron so much below that of iron carbide. Their workpieces won't carburise in the furnace, because they won't be forged. And finally, their iron melts below the Austenite-Marstenite transition temperature, so they wouldn't be able to quench their steel if they did make any.

So, just having lower-temperature iron has no bearing on making steel. That's fine. I'm assuming that means I'll have to use the stats for iron weapons and armor, which have a higher chance to break.

Originally Posted by Agemegos

Crucible steel likely goes back to the Third Century BC in Sri Lanka and southern India. Note well that you need iron, already smelted from its ore, to make crucible steel.

Ok, none of that then.

[Agemegos]

Originally Posted by Seneschal

So, if I understood correctly, under these made-up rules, the iron would be easily cast, but would have the properties of relatively pure iron? So, weapons and armor made from such a material would be softer than steel, but not as brittle?

I think that's right, yes.

By "quite unlike" do you mean they would more easily be made elaborate?

Yes, and things like bells, pots, lamps, helmets, cuirasses, stirrups, basket-hilts and so forth (which were difficult to forge and therefore which continued to be made of bronze or brass long after iron came in for simply-shaped objects such as blades) might be cast in pure iron. Mail might never be invented. Swords might be cast all in one piece with the blade, cross-guard, tang, and pommel.

So, just having lower-temperature iron has no bearing on making steel.

Correct. If anything it is an impediment, since the problems of shaping iron way below its melting-point led to it being heated repeatedly in a bed of hot carbon while it was being forged (and while the refinery bloom was being wrought into bars). It incidentally picked up carbon while that was being done, resulting in mild and case-hardened steel. That won't happen if it is being cast.

There might still be a little carbon in some iron, as a result of iron carbide forming in the blast furnace — it used to be part of the art of a smith to use different parts of the bloom for different qualities owing to different extents of carburisation. But I think there will be less with the iron melting in the furnace, and in any case these people won't be able to harden steel if they do get any, becasue theirs will melt long before it reaches heat-treatment temperatures.

That's fine. I'm assuming that means I'll have to use the stats for iron weapons and armor, which have a higher chance to break.

Yes, the stats should be as for iron. I'm not sure though that "breaking" is exactly right. Blunting and bending, perhaps.