Ternary Phases in the System Au--Cu--Sn.

Investigation of the Phase Equilibria of Sn-Cu-Au Ternary and Ag-Sn-Cu-Au Quaternary Systems and Interfacial Reactions in Sn-Cu/Au Couples

“…Three phase regions, dark, gray, and bright, are observed, and their compositions are, respectively, Sn60at.%Cu-20at.%Au, Sn-25at.%Cu-27at.%Au, and Sn-35at.%Cu-32at.%Au. The dark region is likely to be the ternary IMC-Au 2 Cu 6 Sn 2 , which is named B; 18,40 the gray region is likely to be the AuSn phase; 14 and the bright region is another ternary IMC, Au 33 Cu 34 Sn 33 , which is named C. 18,40 According to the XRD pattern of alloy 21, as shown in Fig. 3b, the diffraction peaks of B, C, and v phases are found, and this result is in agreement with the EPMA analyses.…”

“…According to KarlsenÕs report, a continuous range of homogeneity was found between Cu 6 Sn 5 and AuSn at 360°C. 18 It is reasonable to consider that there exists a complete solid solubility between AuSn and Cu 6 Sn 5 phases in the Sn-Cu-Au ternary isothermal section at 200°C. In this study, the stoichiometric Investigation of the Phase Equilibria of Sn-Cu-Au Ternary and Ag-Sn-Cu-Au Quaternary Systems and Interfacial Reactions in Sn-Cu/Au Couples formula of this continuous solid solution is expressed as Au 5x Cu 6(1)x) Sn 5 , x: 0-1, which is labeled as v phase.…”

“…determined the phase relationship of the Sn-Cu-Au system at 360°C and proposed a continuous solid solution between Cu 6 Sn 5 and AuSn phases. [18][19][20] However, Zakel et al studied the same ternary system at 190°C and found that a two-phase region existed between Cu 6 Sn 5 and AuSn phases. 23 Karlsen observed that three ternary IMCs existed in the isothermal section of the Sn-Cu-Au ternary system at 360°C, but Zakel found that there was only one ternary IMC in it at 190°C.…”

“…Their results were not consistent. The phase equilibria of ternary systems, Au-Sn-Cu, [18][19][20][21][22][23][24] Ag-Sn-Cu, [25][26][27][28][29][30][31][32][33][34] Ag-Sn-Au, [35][36][37][38] and Ag-Cu-Au, 39 at specific temperatures have been published. Regarding the Ag-Sn-Cu-Au quaternary system, no literature is available.…”

“…With regard to Sn-Cu-Au ternary systems, some studies have been done at different temperatures. [16][17][18][19][20][21][22][23][24] Karlsen et al. determined the phase relationship of the Sn-Cu-Au system at 360°C and proposed a continuous solid solution between Cu 6 Sn 5 and AuSn phases.…”