Age-hardening by grain interior and grain boundary precipitation in an Au-Ag-Pt-Zn-In alloy for multipurpose dental use
Year: 2010
Type: article
Abstract: The complex precipitation mechanisms related to the age-hardening of Cu-free Au-Ag-Pt-Zn-In alloy for multipurpose dental use was studied by means of hardness test, X-ray diffraction (XRD) studies, field emission scanning electron microscopic (FE-SEM) observations, energy dispersive spectrometer (EDS) analysis, and electron probe microanalysis (EPMA). The early diffusion and then clustering of the In-concentrated phase in the grain interior, together with the early diffusion and then ordering of the PtZn phase in the grain boundary, introduced the internal strains in the Au-Ag-rich α1 matrix, resulting in the hardening process. As the Au-Ag-rich α 1 ’ and PtZn β lamellarforming grain boundary reaction progressed, the phase boundaries between the solute-depleted face-centered cubic (FCC) α 1 ’ matrix and the face-centered tetragonal (FCT) PtZn β precipitate reduced, resulting in softening. In the particlelike structures composed of the major Pt-Au-rich α2 phase and the minor Pt-Zn-rich α3 phase, the separation of In and Zn progressed producing the In-increased Pt-Au-rich α 2 ’ phase and the Zn-increased PtZn α3′ phase with aging time without restraining the softening. The miscibility limit by complex systems of Au-Pt, Ag-Pt, Au-In and In-Zn resulted in the phase transformation and related microstructural changes.
Source: Gold bulletin
DOI: 10.1007/bf03215001
Authors: Joo-Hee Park, Mi-Hyang Cho, Mi-Gyoung Park, Yong Hoon Kwon, Hyung-Il Kim, Hyo-Joung Seol
Institutions: Pusan National University, Catholic University of Pusan
Language: English
Subfield: General Materials Science
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,390
OpenAlex ID: W2013104249