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Comment by alexpotato | Hacker News Reader

Nice to see Pykrete being mentioned!

https://en.wikipedia.org/wiki/Pykrete

Fun fact: you don't need sawdust for pykrete. Adding any kind of material e.g. just newspapers can help similar to how rebar makes concrete stronger

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Isn't adding newspapers just adding cellulose with some bonus ink?

It adds fiber, which is the key. The main weakness of ice as a crystal is that as soon as a crack forms it can spread along imperfections in the crystal structure. Putting fibre in it bridges those gaps and stops the cracks before they can get big enough to cause significant weakening.

But those fibers disturb the crystal lattice of the ice, so surely there is some tradeoff?

Alloying copper with tin to make bronze produces a material which is stronger and more durable than either component, and this works because the tin disturbs the copper's crystal lattice, which restricts the mobility of dislocations, which in turn reduces the plasticity of the alloy.

I do not know if cellulose fibers have a similar effect in ice, but in general, if you can trade the feature that is causing a problem for one that will not, you are improving things.

Aka it makes it less brittle, which ultimately makes it stronger?

It makes it less ductile, which means it's harder and more resistant to deformation. Bronze is more brittle than copper.

Adding fibres to already brittle materials improves their resilience to tensile forces mostly

So you’re saying it makes it more brittle? Because the opposite of ductile is brittle.

Or are you saying it increase yield strength, because that is a separate property, yes?

pip3 install pykrete

It provides the Krete framework for building your vacation to Crete island.

brew install pykrete

uv add pykrete

Jeez cmon

Came to the comments for the pykrete reference, thanks for this.

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