Applications in Materials Processing

Use of supercritical fluid in manufacturing fine particles.

Using the Rapid Expansion of Supercritical Solutions (RESS) method, the solute is dissolved in supercritical fluid and then is expanded through a nozzle to a low density in the vicinity of atmospheric pressure. Ball-shaped or fibrous fine particles are obtained.
Kobe Steel has developed a process for manufacturing fine silica particles or minute fibrous material, in which the monocrystalline silica is dissolved in supercritical water. In addition, an improved version of the RESS method is used.

Photo 3 SEM image of SiO2 particles (823K,100MPa)

Photo 4 SEM image of SiO2 particles (823K, 63MPa)