(Sn-Ag)eut+Cu soldering materials, part I: Wettability studies

Abstract

The maximum bubble pressure, dilatometric, and meniscographic methods were used in investigations of the surface tension, density, wetting time, wetting force, contact angles, and interfacial tension of liquid (Sn-Ag) eut and two (Sn-Ag) eut + Cu alloys (Cu at.% = 0.46 and 0.74). The density and surface tension measurements were conducted in the temperature range from 230 to 950°C, and the meniscographic investigations were carried out at 252°C. The resultant values of surface tension were compared with those calculated from Butler's model based on optimized thermodynamic parameters and our data from earlier investigations. In an earlier study, experimental data for all investigated compositions (Cu at. % = 1.08 to 6.5) exhibit an increase in the surface tension with interesting temperature, while both ternary alloys of this study show a slight lowering tendency in comparison to (Sn-Ag) eut . A more evident decreasing tendency of surface tension and interfacial tension was noted in meniscographic measurements, noting that data of interfacial tension are always lower than surface tension due to the role of the flux. Eight different fluxes were tested to select the lowest interfacial tension for the (Sn-Ag) eut . ROLI (3% solids), which is the alcoholic solution of organic compounds and rosin activated by halogens, was recommended. In (Sn-Ag) eut + Cu Soldering Materials, Part II: Electrical and Mechanical Studies, for the same (Sn-Ag) eut and (Sn-Ag) eut + Cu alloys (Cu at. % = 0.46 and 0.74), the electrical resistance and strength measurements will be presented in parallel with printed-circuit boards in wave soldering at 260°C.

Influence of Zinc on the Surface Tension, Density and Molar Volume of (Ag-Sn)eut +Zn Liquid Alloys

“…4 and their elaborated linear equations are presented in Table 3 fig. 4. temperature dependences of the surface tension for the (AgSn)eut +Zn liquid alloys.…”

“…The determination of the density was conducted with the use of the mentioned below relation: (4) where: r is the density, m is the mass of the metal or alloy, d is the crucible diameter and h is the height of the metal or alloy in the crucible.…”

“…These studies have led to the development of new lead-free solders for electronics and electrical engineering. Initially, the research for the physical properties was focused on binary systems (Pb-Sn [1,2] and Ag-Sn [3]), and then, it was expanded to multicomponent systems on the base of the AgSn eutectic, including also wettability and microstructural studies [4,5]. The studies were also carried out in the frames of the programs COST 531 (low-temperature solders) [6,7] and COST MP 0602 (high temperature solders) [8], as well as projects financed by the Polish Government and in the cooperation with Tohoku University and industrial Institutes [9].…”

Database of Pb - free soldering materials, surface tension and density, experiment vs. Modeling

“…In Table 1 there are summarized the updated investigated systems with references: (Gąsior, Moser & Pstruś, 2001); (Moser, Gąsior & Pstruś, 2001a); (Moser, Gąsior, Pstruś, Zakulski, Ohnuma,. Liu et al, 2001c); (Moser, Gąsior & Pstruś, 2001b); (Gąsior, Moser, & Pstruś, 2003a); (Moser, Gąsior, Ishida, Ohnuma, Liu, Bukat et al, 2005b); (Pamies, Garcia-Cordovilla & Louis, 1984) (Nogi, Oishi & Ogino, 1989); (Gąsior, Moser & Dębski, 2004c); (Liu, Inohana, Ohnuma, Kainuma, Ishida, Moseret al, 2002); (Gąsior, Moser, Pstruś, Krzyżak & Fitzner, 2003b); ; (Moser, Gąsior & Pstruś, 2005a); (Gąsior, Moser, Pstruś, Bukat, Kisiel & Sitek, 2004e); (Moser, Gąsior, Pstruś & Księżarek, 2002); (Moser, Gąsior, Pstruś, Ishihara, Liu, Ohnuma et al, 2004d); (Gąsior, Moser & Pstruś, 2004b); (Moser, Gąsior, Ishida, Ohnuma, Bukat, Pstruś et al, 2004c); (Gąsior, Moser, Bukat, Pstrus, Sitek, & Kisiel, 2004d); (Kisiel, Gąsior, Moser, Pstruś, Bukat & Sitek, 2005). (Gąsior et al, 2001) Pb -Sn (Gąsior et al, 2001) (Sn-Ag) eut +Zn * Sn (Moser et al, 2001a) Ag -Sn (Moser et al, 2001a) (Sn-Ag) eut +In (Liu et al, 2002) In (Moser et al, 2001c) Ag -In (Moser et al, 2001c) (Sn-Ag) eut +Bi (Moser et al, 2001b) Ag (Moser et al, 2001c) Bi -Sn ) (Moser et al, 2001b) (Sn-Ag) eut +Cu (Gąsior et al, 2004e) ) Bi (Moser et al, 2001b) In -Sn (Liu et al, 2002) (Sn-Ag) eut +Sb Sb (Gąsior et al, 2003a) Ag -Bi …”

“…The wetting balance test can be used to observe the dynamic process of wetting by measuring the force that acts between the immersed specimen and the molten solder. In a recent publication on addition of Cu to binary eutectic Sn-Ag (Gąsior et al, 2004e), we reported the joint results with industrial institutes dealing with the production and testing of Pb-free solders to combine data of the surface tension from measurements in a protective atmosphere with the results from meniscographic studies. This was possible using two different meniscographs and performing measurements on wetted and not wetted specimens in air.…”