Premium
USE OF TORSIONAL STRESSES FOR OBSERVING HIGH‐TEMPERATURE CHARACTERISTICS OF CERAMIC MATERIALS *
Author(s) -
Decker Alfred R.,
Royal Herbert F.
Publication year - 1948
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1948.tb14248.x
Subject(s) - materials science , composite material , torsion (gastropod) , ceramic , creep , orthotropic material , ultimate tensile strength , tensile testing , structural engineering , engineering , medicine , surgery , finite element method
A bstract A method is described for testing ceramic specimens under torsional stresses at temperatures to 2500 °F. With simple apparatus and minimum time, consistent values are obtained for modulus of rigidity, Poisson's ratio (when the modulus of elasticity is known), tensile (torsion) strength, torque‐twist graph, approximate softening temperature, plastic deformation, and short‐time creep rate. The results are in satisfactory agreement with tensile test, bending test, and long‐time creep‐rate results and thus provide a quick means of making a preliminary selection of promising compositions for more extensive testing. Among the advantages of torsion testing are freedom from error caused by thermal expansion, absence of need for close dimensional tolerances, simplicity of specimen installation in grips, and the ability to make deformation measurements outside the furnace on the cool end of the specimen. Data for a sillimanite body and a beryl‐lia body illustrate the types of information given by the method. The beryllia body has more suitable high‐temperature characteristics.