Objective: The cushioning effects of casting ling liners were evaluated. Materials and Methods: The cushioning effects of casting ring liners on the setting expansion of the investment material in split metal molds with internal dimensions of 30 mm diameter and 40 mm height were evaluated based on the decrease in the thickness of fourteen dry ceramic liners and three asbestos ribbons. Five millimeters of clearance is allowed at each end of the mold. Cristobalite model investment powder was mixed with water under a vacuum, then the mold was filled with the mixture. Twenty-four hours after the filling, set investment and liners were taken out from the mold, then liners were removed from the investment surface as much as possible. Diameters of investment cylinder were measured in the position of 10, 20, 30 mm from the upper edge by 3D coordinate measuring machine. Results: Setting expansion of investment materials was 0.28%, and requirement of decrease in thickness of liners was 0.03 mm. Decreases in the thickness of liners (δTs) were -0.138 to 0.151 mm. Differences between δTs at 10 mm and 20 mm, at 10 mm and 30 mm, and δTs at 20 mm and 30 mm were not significant (p>0.05) in all ceramic liners, and were significant (p<0.05) in three asbestos ribbons. Conclusion: Setting expansion of the investment material was restrained, when 12 kinds of ceramic liners were used.
Division: Japanese Division Meeting
Meeting:2005 Japanese Division Meeting (Okayama, Japan) Location: Okayama, Japan
Year: 2005 Final Presentation ID:76 Abstract Category|Abstract Category(s):Scientific Groups
Authors
Yagihara, Kenji
( Nihon University, Tokyo, N/A, Japan
)
Hirose, Hideharu
( Nihon University, Tokyo, N/A, Japan
)
Hiraguchi, Hisako
( Nihon University, Tokyo, N/A, Japan
)
Sakaguchi, Setsuko
( Nihon University, Tokyo, N/A, Japan
)
Nishiyama, Minoru
( Nihon University, Tokyo, N/A, Japan
)