| 摘要 |
PURPOSE:To economically and readily obtain a ceramics having extremely high transparency and denseness by burning a ceramic-formed article consisting of each oxide of lead, lanthanum, zirconium and titanium for a short time, fabricating the burned article into a prescribed thickness and then subjecting the treated burned article to a short-term hot isostatic pressing treatment. CONSTITUTION:The composition of the objective ceramic satisfies the formula (Pb1-xLax)(ZryTiz)1-x/4O3 (x=0.087-0.093; y/z=0.06/0.34-0.64/0.36) and has 0.5-5mum average crystal grain size, 0.633mum measured wavelength and >=60% light transmittance based on a condition containing scattering light and reflection loss. The ceramic is obtained as follows: A ceramic-formed article consisting essentially of each oxide of Pb, La, Zr and Ti is in a vacuum of 1X10<-2>-1X10<-5>Torr at 1150-1250 deg.C for 0.5-2hr and the burned article is fabricated into <=1.5mm thickness to form a thin plate. Then the thin plate is embedded in a pressure vessel in which powder consisting of at least one kind of melt type Al2O3, melt type ZrO2 and melt type MgO and having 50-3000mum grain size is closely packed and subjected to a hot isostatic pressing treatment under inert gas atmosphere at 1050-1200 deg.C and 500-700kg/cm<2> for 0.5-2hr. |
