Effect of casting temperature and atmosphere on castability of Ni-Cr alloys: a comparative study with direct flame casting method

Autor(es)

Osvaldo Luiz Bezzon ^[1] ; Celso de Barros ^[2] ; Valéria Oliveira Pagnano ^[3] ; Natércia Carreira Soriani ^[4]

Afiliação do(s) autor(es)

^[1] University of São Paulo. School of Dentistry of Ribeirão Preto. Department of Dental Materials and Prostheses - Brasil

^[2] University of São Paulo. School of Dentistry of Ribeirão Preto. Department of Dental Materials and Prostheses - Brasil

^[3] University of São Paulo. School of Dentistry of Ribeirão Preto. Department of Dental Materials and Prostheses - Brasil

^[4] University of São Paulo. School of Dentistry of Ribeirão Preto. Department of Dental Materials and Prostheses - Brasil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 9, n. 2, p. 237-241, 2006-06-00.

Resumo

The purpose of this study was to compare the effect of casting temperature and atmosphere on the castability of three Ni-Cr alloys against direct flame casting method. Vera Bond (VB), Vera Bond 2 (VB2) and Wiron 99 (W99) were cast at three temperatures: VB and VB2 (1310 °C, 1340 °C and 1370 °C); W99 (1400 °C, 1430 °C and 1460 °C) in atmosphere, vacuum and direct flame. Each alloy was cast in seven different conditions. Castability was assessed by the method that verifies the alloy potential to reproduce a nylon mesh. Kruskal-Wallis test demonstrated for VB, while there was no influence in the temperature range, castability was greater by vacuum (99.3%) than by direct flame (96.2%) and atmosphere (93.06%). For VB2, castability was greater at evaluated temperatures (1370 °C = 94.4%, 1340 °C = 91.15% and 1310 °C = 87.9%) than direct flame (77.8%); related vacuum (97.33%) obtained better values than atmosphere (84.6%) and direct flame. For W99, while atmosphere had no influence, castability was higher at 1460 °C (84.3%) than at other temperatures (1430 °C = 70.3%, 1400 °C = 37.05%) and direct flame (62.5%). Comparison among interactions showed that for all alloys it was possible to significantly increase the filling percentage of the mold in a comparative manner with the direct flame cast method. (AU)

• Processo FAPESP: 96/11874-4 - Estudo comparativo entre propriedades físicas do titânio puro processado por cera perdida em relação as ligas odontológicas de Ni-Cr e Co-Cr
• Beneficiário: Osvaldo Luiz Bezzon
• Modalidade de apoio: Auxílio à Pesquisa - Regular