Physical and material characteristics for Eragon. Heat conduction ties to physics.md; structural use of materials ties to structure.md.

• Thermodynamics
• Crystallography
• 3D printing
• Scientists

• How efficiently electrons (and the lattice) transfer thermal energy through a material

• Speed of heat spreading through a material

• Net movement from higher concentration toward lower concentration

• Surface property: shiny surfaces tend to reflect rather than radiate

• Rate of heat transfer inside a material
• “How quickly temperature concavity (thermal ‘acceleration’) is smoothed out”
• High thermal diffusivity → heat moves quickly relative to the material’s thermal bulk (energy storage capacity)

• Physical measurement: pulse one end of a strip/cylinder with a short energy burst and measure how temperature arrives at the far end

• Dimensionless number for unsteady heat conduction
• Compares conduction rate to heat-storage rate:

$$ Fo = \frac{\alpha \tau}{L_c^2} $$

• $\alpha$ — thermal diffusivity
• $\tau$ — time (s)
• $L_c$ — characteristic length (often volume / surface area)

• Study of crystalline structures and properties
• Natural crystal shapes reflect atomic arrangement

• Annealing proceeds by diffusion of atoms within a solid

• Heat treatment
• Heating lets atoms migrate into a more ordered crystal lattice

• Also called additive manufacturing

• Common 3D-printing filament
• Low heat resistance — deforms around ~$60\degree\mathrm{C}$
  • Annealing can improve heat resistance
• Produced by condensation of lactic acid with loss of water