Samples of strontium hexaluminate (SrAl12O19), both pure and mixed with different amounts of ceria-stabilized zirconia (CE-TZP), have been prepared via a chemical route. The fluorescence spectrum of SrAl12O19 is similar to that of ruby and yttrium aluminium garnet (YAG); consequently, this similarity has been attributed to the presence of a trace impurity of Cr3+ ions. The most-intense fluorescence peak of SrAl12O19 exhibits a dependence on stress that is given by the average uniaxial piezospectroscopic coefficient (< II > = 1.5 cm(-1).GPa(-1)). The piezospectroscopic coefficient has been used to convert to stress the fluorescence frequency shift of SrAl12O19 mixed with zirconia (ZrO2). The stress, as a function of the volume fraction of ZrO2, resides between the Hashin-Shtrikman bounds but is best reproduced by an effective medium approximation.
Piezospectroscopic analysis of the residual stresses in the strontium hexaluminate/zirconia (SrAl12O19/ZrO2) system
MASCHIO, Stefano;
1999-01-01
Abstract
Samples of strontium hexaluminate (SrAl12O19), both pure and mixed with different amounts of ceria-stabilized zirconia (CE-TZP), have been prepared via a chemical route. The fluorescence spectrum of SrAl12O19 is similar to that of ruby and yttrium aluminium garnet (YAG); consequently, this similarity has been attributed to the presence of a trace impurity of Cr3+ ions. The most-intense fluorescence peak of SrAl12O19 exhibits a dependence on stress that is given by the average uniaxial piezospectroscopic coefficient (< II > = 1.5 cm(-1).GPa(-1)). The piezospectroscopic coefficient has been used to convert to stress the fluorescence frequency shift of SrAl12O19 mixed with zirconia (ZrO2). The stress, as a function of the volume fraction of ZrO2, resides between the Hashin-Shtrikman bounds but is best reproduced by an effective medium approximation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
