1988 Volume 52 Issue 5 Pages 523-528
Using a high temperature range torsion test apparatus, the shape recovery property of the three mica glass-ceramics are clarified. These mica glass-ceramics investigated have almost equal microstructures of mica/glass mixture but are different in chemical composition of the glass matrix. Moreover, the difference in the recovery behavior of the mica glass ceramics is investigated. The results are summarized as follows:
(1) It was found that the shape memory phenomenon occurs in the mica glass-ceramics called ‘MACERITE’ or ‘PHOTOVEEL’ which are different from ‘MACOR’ in chemical composition of the glass matrix.
(2) The pre-deformation temperature range and the shape recovery temperature range, in which the shape recovery property is best, changes by the chemical composition of the glass matrix.
(3) The effect of the prestrain and the prestrain rate on the shape recovery property does not change so much by the chemical composition of the glass matrix.
(4) The stress relaxation temperature range corresponds to the shape recovery temperature range in all cases.
(5) The thermal expansion curves show that corresponding to the shape recovery temperature range, there is a break point which suggests the glass transition point of the glass matrix in all of the three mica glass-ceramics.
