Abstract
The cushioning effects of wet casting ring liners on the setting expansion of investment materials were evaluated by the cushioning ability in 15 wet ceramic liners (A:rockwool type, B:ceramic fiber low temperature type, C:ceramic fiber standard type, D:ceramic fiber low temperature standard type, E:kaolin type)and 3 wet asbestos ribbons (AS).Wet liners were seated inside the sliding frame of an appratus for expansion measurement, and then the setting expansion was measured for 120min.Cushioning effects were calculated by the difference between the setting expansion without liner and the setting expansion with liner. The cushioning effects of wet liners were classified into three groups.(1) No cushioning effect of wet liners in group A and one product in group D, where the filling rate of water in the vacant space of the liner was high.(2)Good cushioning effect of wet liners in group E and AS, where the filling rate of water was high.(3)Good cushioning effect of wet liners in group B, C and D (except for one product), where the filling rate of water was low.
