[High temperature investments. 1. Evaluation of some physical properties].
An evaluation of linear dimensional alterations of normal and hygroscopic setting of 3 phosphate-bonded investments and gypsum-bonded investments was made. The phosphate-bonded investments were processed with 100, 75, 50 and 25% special liquid. We investigated the maximum temperatures tolerated by the investments, in relation to the normal setting reactions. To evaluate expansion of normal and hygroscopic setting an electronic palpater was used, with the investments confined. The temperatures of the thermal reactions were detected by a digital thermometer. We confirmed that the CERAMIGOLD and HI-TEMP investments, processed with 75% special liquid, presented a greater linear expansion than the normal settings. The HI-HEAT presented less expansion than the normal setting and greater linear expansion than the hygroscopic setting. The MULTI-VEST tolerated the highest temperature during the evaluation.
Fernandes
R M
RM
Roselino
R B
RB
Campos
G M
GM
Abraão
W
W
D002133:Calcium Sulfate; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003734:Dental Casting Investment; D006358:Hot Temperature; D008422:Materials Testing; D010710:Phosphates
D003734:Dental Casting Investment; D010710:Phosphates; D002133:Calcium Sulfate
Revestimentos para altas temperaturas. Parte I. Avaliação de algumas propriedades físicas.