Avaliação da fundibilidade de uma liga de cobalto-cromo

Abstract

The purpose of this study was to evaluate the castability of a cobalt-chromium alloy (Vera-PDI) using three investments: Knebel (agglutinated by silica), Termocast and Wirovest (both agglutinated by phosphate) at two molding temperatures (900°C and 950°C); using HINMAN et al.9 (1985); methodology. The casting method of using a wax and gas-oxygen flame was used. There was no significant statistical difference between the Knebel and Wirovest investments; however, there was a statistically significant difference for Termocast investment (P < 0.1) at the different temperatures. When analyzing the investments at 900° C there was a statistical difference between Knebel and Termocast and Knebel and Wirovest at P < 0.1 and for Termocast and Wirovest at P < 0.05. At 950°C there was a statistically significant difference (P < 0.1) for all coatings. According to the parameters of this study, we conclude that the best results were obtained for the Vera-PDI alloy when we use the Knebel investment and 950°C for casting.