At present, there are many kinds of lead-free solders with ever-changing alloys. The alloy composition includes binary system, ternary system and polynary system.??
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Generally, most of them are composed of Sn, with appropriate addition of Ag, Zn, Cu, Sb, Bi, In and other metallic elements. With the different alloys, the properties of solders can be optimized, then to get an ideal mechanical, electrical and thermal properties.?
產(chǎn)品特性與優(yōu)勢
·??Good Mechanical Properties
·? Superior electrical conductivity
·? High thermal conductivity
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Typical Products
Sn-Ag-Cu Preforms
Sn-Ag-Cu (SAC) is the most common alloy in soldering electronics. Such as those alloys whose melting point is around 217℃, like SAC105(Sn98.5Ag1Cu0.5), SAC305 (Sn96.5Ag3Cu0.5)、SAC387(Sn95.5Ag3.8Cu0.7) and SAC405(Sn95.5Ag4Cu0.5) are usually used in reflow, wave and manual soldering.?
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Among above, SAC305 are more wildly used. Compared with Sn63Pb37, it has better performance on stiffness, tensile strength, yield strength, shear strength, impact strength and creep strength;? compared with Sn-Cu/Sn-Ag preforms, it’s wetting properties are better.
Model
|
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Bi58Sn42 |
Bi57Sn42Ag1 |
Sn98.5Ag1.0Cu0.5 |
SAC305(Sn96.5Ag3.0Cu0.5) |
Sn95.5Ag3.8Cu0.7 |
SAC405(Sn95.5Ag4.0Cu0.5) |
Sn96Ag3.5Cu0.5 |
Sn96.5Ag3.5 |
Sn95Ag5 |
Sn95.5Ag3.9Cu0.6 |
Sn99Ag0.3Cu0.7 |
Sn95Sb5 |
Solid Line
°C |
Liquidus
℃ |
Eutectic Alloy
℃ |
Density
g/cm3 |
Resistivity
μΩ.m |
Thermal Conductivity
W/m.K |
Thermal Expansion Coefficient
10-6/℃ |
Tensile Strength
Mpa |
---|---|---|---|---|---|---|---|
/ | / | 138 | 8.56 | 0.383 | 19 | 15 | 55.16 |
138 | 140 | / | 8.57 | / | / | / | / |
217 | 227 | / | 7.32 | 0.133 | 60 | / | 40 |
217 | 218 | / | 7.37 | 0.132 | 58 | 21 | 50 |
217 | 220 | / | 7.4 | 0.132 | 57 | 22 | 48 |
217 | 220 | / | 7.4 | 0.132 | 62 | / | 51.5 |
217 | 218 | / | / | / | / | / | / |
/ | 221 | / | 7.37 | 0.108 | 33 | 30 | 39 |
221 | 240 | / | 7.4 | 0.137 | / | 23 | 55.2 |
217 | 220 | / | / | / | / | / | / |
217 | 227 | / | / | / | / | / | / |
235 | 240 | / | 7.25 | 0.145 | 28 | 31 | 40.7 |