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

[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.