Field emission gun electronprobe microanalysis (FEG-EPMA) provides the analyst with the opportunity to characterize very small volumes of material. Using a low voltage source the irradiated volume is submicron. It is well known that some geological phases e.g. volcanic glass, carbonates, phosphates, hydrous silicates suffer beam damage under high beam current condition [e.g.1,2] and several aut...

Age-hardening characteristics in a dental low-gold alloy composed of 40.0 wt% Au-35.0 wt% Ag-7.9 wt% Pd-7.0 wt% Cu-5.0 wt% In-3.5 wt% Zn-1.5 wt% Sn, were investigated by means of the hardness test, XRD study, SEM observations and EPMA. The following results were obtained. The age-hardening was characterized by a precipitation of Cu-rich alpha2 phase in the a phase. The softening that occurred f...

A correction procedure is proposed to correct for the effects of characteristic fluorescence in EPMA near phase boundaries. The necessary equations for the simple case of two homogeneous alloys sharing a common interface are given. The equations have been tested in practice and it is shown that they are well suited to predict the apparent concentration of the element suffering from secondary ex...

Octahedrally-coordinated Cr(3+) possesses peculiar spectral features which made easy to identify it in minerals, even in minor amounts. Chromium has been studied in uvarovite and fuchsite by optical and EPR spectra. Optical, EPR, FT-infrared and EPMA studies have also let to determine the presence of Fe(3+) and Ti(3+) and fluid inclusions within uvarovite and fuchsite. Absorption and scattering...

Garnet-like oxides having the formula Li7+X−YLa3−XAXZr2−YNbYO12 (A = Sr or Ca) were synthesized using a solid-state reaction, and their bulk and grain boundary resistivities were assessed by AC impedance measurements. A difference in grain boundary resistivity was identified between Sr and Ca materials, and so the grain boundaries were examined using electron probe microanalysis (EPMA). The dif...