Abstract
Fluidity determination was conducted using silica tube as the fluidity channel and a regulated vacuum system. Fluidity tests were made in which Fe-Si, Ca-Si, Ca-Si-Ba and Ca-Si-Ba-Al were added to hypoeutectic cast iron melt. A linear relation between fluidity length and tube diameter is obtained. Fluidity length increases with increasing suction pressure and with increasing temperature of melt. Fluidity length is propotional to the square root of effective suction pressure. Structure zone of fluidity specimens is classified into three regions from tip backward : ledeburite, mottle and flake graphite structure. The Length of each structure zone increases with increasing suction pressure. Ledeburite structure zone decreases with increasing tube diameter, but the total length of ledeburite zone and mottle zone is constant for increasing tube diameter. Thus, the flake graphite zone increases linearly with tube diameter. With increasing holding time, fluidity length increases up to 10 minutes and then decreases.
