Professor Takayuki Watanabe of Kyushu University, has developed a technology to dissolve metals and rocks.

By water plasma, it produces a flame of 10000 ℃.
 

All of metal and rock are burned and are changed to gas.

This is not a melt phenomenon.

It becomes air.
 

Currently, it has been used to extinguish the metal waste.

However, if this technology evolution, human and weapons can alter to the air.
In other words, as of dynamite and nuclear science, this technology contributes to the human, but may be become a weapon.

As of SF movie.

 This science technology should be limited only to the peaceful use.
 

http://www.bsfuji.tv/pub/kakushin/index.html

http://www.chem-eng.kyushu-u.ac.jp/lab5/Media/PDF/WasteTreatmentEng.pdf