Lead Free Solder alloys

Alloy

 Remarks

Ag

Bi

Cu

In

Sb

Sn

Liq T

Sol T

Density

SBI 79
Low melting alloys with Bismuth and tin. Also, these are purposely used alloys with copper and silver additions.

 

57.0

 

26.0

 

17.0

79

79

8.54

SBI 81

 

54.0

 

29.7

 

16.3

81

81

8.47

BI 109

 

67.0

 

33.0

 

 

109

109

8.81

SI 118

 

 

 

52.0

 

48.0

118

118

7.30

SI 128

 

 

 

75.0

 

25.0

128

132

7.30

SB 138

 

58.0

 

 

 

42.0

138

138

8.56

SBC 198

 

9.5

0.5

 

 

90.0

198

198

7.55

SBA 205

3.4

4.8

 

 

 

91.8

205

212

7.51

SABC 215
Popular Range of lead free tin with silver and copper alloys mostly used and recommended world wide

4.5

1.5

1.5

 

 

92.5

215.5

215.5

7.51

SAC 405

4.0

 

0.5

 

 

95.5

216

219

7.36

SAC 410

4.0

 

1.0

 

 

95.0

216

219

7.36

SAC 305

3.0

 

0.5

 

 

96.5

 

 

 

SA 350
Tin and silver alloys for Solder bath additions without copper

3.5

 

 

 

 

96.5

221

221

7.36

SA 250

2.5

 

 

 

 

97.5

221

226

7.34

SA 400 (SABS 20)

4.0

 

 

 

 

96.0

221

238

7.36

SC 997
Tin and copper alloys used for many years mainly in industrial applications

 

 

0.7

 

 

99.3

227

227

7.32

SC 991

 

 

1.0

 

 

99.0

227

227

7.32

SC 973 (SABS 19)

 

 

3.0

 

 

97.0

230

250

7.30

SB 973
Higher melting alloys with antimony for wave solder applications

 

 

 

 

3.0

97.0

232

238

7.26

SB 955 (SABS 18)

 

 

 

 

5.0

95.0

232

240

7.25

SAS 2510

25.0

 

 

 

10.0

65.0

233

233

7.80

SS 991

 

 

 

 

1.0

99.0

235

235

7.27

 

Proposed Contamination Levels by IPC Report on SAC 305 LF Solders

 

Contaminant Normal Balance Increase Pot Monitoring Adjust Pot
Tin Balance >97.25% >97.5%
Arsenic <0.02% >0.02% >0.03%
Antimony2 <0.05% >0.05% >0.2%
Gold 0-0.03% 0.08% 0.2%
Iron 0.01% >0.01% >0.02%
Nickel <0.01% >0.025% >0.05%
Bismuth ≤0.03% >0.03% >0.25%
Aluminum ≤0.001% >0.002% >0.006%
Copper <0.6% >0.8% 1.1%
Silver <3.2% >3.5% >4.0%
Zinc <0.003% >0.003% >0.005%
Cadmium ≤0.001% >0.002% >0.005%
Indium <0.01% >0.01% >0.10%
Lead     >0.10%

 

* These are only indicative values and should be correctly calculated, when used in any design or application.