| 摘要 |
PURPOSE:To obtain a desired diaphragm with a simple process without requiring processes for forging, rolling, etc. by discharging a molten material onto the surface of a roller under rotation to form a thin sheet and forming the thin sheet into the shape of the diaphragm. CONSTITUTION:An Mg-base alloy is put into a crucible 1 and the inside of the crucible is heated by a high-frequency coil to melt the alloy. The alloy is melted and thereafter the crucible 1 is lowered to maintain the prescribed space between a slit 3 and the roller 4. The roller 4 is rotationaly driven and gaseous Ar is introduced into the crucible 1 to pressurize the molten metal. The molten Mg- base alloy is discharged through the slit 3 onto the surface of the rotating roller 4 provided below the slit in proximity thereto. The molten Mg-base alloy which contacts with the roller 4 is extended and thinned and at the same time the alloy is quickly cooled and solidified. The resultant thin sheet is cut out to a sectorial shape and the end faces 51a, 51b thereof are joined to each other, by which the cone shaped diaphragm 51 is completed. |
