A little off track but I was pondering the reason why the CO2 would cut steel but not aluminium? I've cut paper and cardboard with a CO2 but never tried metal as it might reflect somewhere unwanted. Anyway.
The Laser works by coherent light beam which adds energy to the metal (things it hits) by the electrons absorbing the wave (and presumably parts of the nucleus of the atom) which raises it to ionisation levels...a simple Bohr atom model here. With so much energy there is ionisation..breaking atomic bonds...aka it cuts the metal.
Now Aluminium and steel can be described as a ionic lattice with a sea of de-localised electrons (which give the metal lustre). Steel is an iron/carbon lattice alloy, aluminium is usually alloyed with manganese.
Aluminium is a group 13 element with more core charge (more electronegative element) but a lower melting point than steel. But, aluminium also has a much larger ionisation energy than Steel. The beam wave length cannot promote or excite an Aluminium electron to ionise easily. So I'm assuming that the sea of de localised electrons (ionic bond) and ionisation energy required has something to so with the fact the Laser wouldn't cut Aluminium.
So the Aluminium doesn't really reflect the beam. The Beam cannot ionise the atoms electrons to free them...aka make a cut.
Does that make any sense? Anyone here knowledgeable on atomic models? Ionisation energy of elements?
All very intriguing
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