Evaluation of the amalgamation reaction of experimental Ag-Sn-Cu alloys containing Pd using a mercury plating technique.
A mercury plating technique was used to determine the phases forming on experimental Ag-Sn-Cu alloy powders (with and without Pd) exposed to electrolytically deposited mercury. Four series of alloy powders were made: a) 1.5% Pd with 10-14% Cu (CU series); b) 1.0% Pd with 10-14% Cu (1PD series); c) 1.5% Pd with different ratios of Ag3Sn (gamma) to Ag4Sn (beta) with 12% Cu (AGSN series); and d) 9-13% Cu with no Pd (NOPD series). Each powder was pressed on a freshly prepared amalgam specimen made from the same powder and metallographically polished until cross sections appeared; mercury was electroplated on the alloy particles. Alloy powders, amalgams and electroplated specimens were examined using XRD and SEM/EDS. XRD confirmed the presence of gamma2 in amalgams made from alloys with Cu < 13% or with Ag3Sn/Ag4Sn > 0.8. Specimens with moderately plated Hg showed gamma1 (Ag2Hg3) polyhedra and eta' Cu6Sn5, but not gamma2. This method effectively identifies alloys prone to forming gamma2.
Koike
Marie
M
Nagasaki University Graduate School of Biomedical Sciences, Department of Developmental and Reconstructive Medicine, Division of Removable Prosthodontics, 1-7-1 Sakamoto, Nagasaki, 852-8588 Japan.
Ferracane
Jack L
JL
Fujii
Hiroyuki
H
Okabe
Toru
T
D003300:Copper / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D003723:Dental Amalgam / Q000737:chemistry*; D003775:Dental Polishing; D004577:Electron Probe Microanalysis; D004595:Electroplating; D006801:Humans; D008422:Materials Testing; D008628:Mercury / Q000737:chemistry*; D008669:Metallurgy; D008855:Microscopy, Electron, Scanning; D010165:Palladium / Q000737:chemistry*; D044367:Phase Transition; D011208:Powders; D012834:Silver / Q000737:chemistry*; D014001:Tin / Q000737:chemistry*; D014961:X-Ray Diffraction
D003722:Dental Alloys; D011208:Powders; D012834:Silver; D010165:Palladium; D014001:Tin; D003300:Copper; D003723:Dental Amalgam; D008628:Mercury