Please, explain to me then what you mean by "Plasma torches cut steel (or melt steel) or many other metals at room temperature."butcher said:g_axelsson said:Excuse me, but that's just a stupid statement. The plasma and the steel being removed is way higher than room temperature. All that electrical power going into the plasma torch ends up as heat.butcher said:Plasma torches cut steel (or melt steel) or many other metals at room temperature.
If you still believe that it cuts at room temperature, put your hand on the other side of the steel and see how bad it burns at room temperature.
Göran
I can melt gold, at a room temperature of 72 degrees F, with a high-temperature plasma arc where the temperatures inside the plasma can range from 5,000K to 20,000K.
What is stupid about that statement?
I did not say the localized plasma arc or the ionization area was at room temperature.
What does the temperature of the room have to do with melting metals?
How is this statement different than if I said I can melt a few atoms of gold with a laser beam at a room temperature of 72 degrees F viewed under a microscope?
What does the temperature of the room have to do with anything here?
If the plasma arc is at 5000-20000 K then it isn't room temperature. Room temperature is approximately 393K.
The report states that the gold melted while still at room temperature (probably slightly higher than 400K)
If you use a laser beam, a plasma torch or a mapp torch to melt gold it still melts at around 1400 K. It is just different ways to increase the temperature (vibrational energy) in the gold up until the point where it melts.
Increasing the electrical field to get the gold melting at the surface at 400K is a totally different process. Apparently the binding energies at the surface are affected and the gold melts. And the molten gold is at room temperature while molten.
Another example of how the melting point can vary depending on external factors is the phase diagram of water, at 200MPa pressure water melts at -20C while under normal atmosphere pressure it melts at 0C.
http://www1.lsbu.ac.uk/water/water_phase_diagram.html
You could easily measure the temperature and while compressing water will heat it up slightly it is easily cooled down and it is the measured temperature that is entered in the diagrams.
Göran