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What is the melting point of lead solder wire and lead-free solder wire?

2019-08-14 17:14:26 Sources: Shenzhen Xinghongtai Tin Industry Co., Ltd. 2611

In electronic and electrical products, solder wire is one of the least indispensable connecting materials, with an average annual consumption of around 100,000 tons. When welding with solder wire, we should effectively control the temperature so that the solder wire has a good soldering effect.


We usually say that solder refers to tin-lead or tin-silver-copper solder alloy. Under normal circumstances, the melting point of tin is 231.9 ° C, the melting of lead is 327.502 ° C, the melting point of copper is: 1084 ° C, the melting point of silver is: 960.8 °C.


In general, the melting point of the tin bar alloy is lower than the melting point of any one of the constituent metals. Taking lead solder (63% tin content, 37% lead content) as an example, the melting point of the formed lead solder is about 183 °C. The lead-free solder melting point is (tin 99.3%, copper 0.7%) around 220 °C.


In order to meet the requirements of some special solder high melting point and high temperature products, our company has specially introduced high temperature soldering strips, the operating temperature can be maintained at 400 °C-500 °C, the solder surface is bright, static at 400 °C ± 10 °C for 12 hours, keep the mirror Does not change color. The amount of slag is only about 1/7 of that of ordinary solder. It is suitable for wave soldering and hot dip soldering. It is especially suitable for the tin-solding of self-solving enamel in various transformer manufacturing.


Lead-free solder wire and lead-free solder wire melting point: 


Lead solder wire melting point:

1) 63/37 solder wire has a melting point of 183 ° C

2) 60/40 solder wire has a melting point of 185 ° C -190 ° C

3) 55/45 solder wire has a melting point of 187 ° C -202 ° C 

4) 50 / 50 solder wire has a melting point of 190 ° C -216 ° C

5) The melting point of 45/55 solder wire is 192 ° C -227 ° C 

5) The melting point of 40/60 solder wire is 194 ° C -238 ° C

6) 35/65 solder wire has a melting point of 198 ° C -247 ° C 

7) 30 / 70 solder wire has a melting point of 202 ° C -256 ° C


Lead-free solder wire melting point:

1) The melting point of Sn-Cu-Ni solder wire is 225 ° C -227 ° C

2) The melting point of Sn-Cu-Ag solder wire is 211 ° C -219 ° C

3) The melting point of Sn-Bi-Ag solder wire is 205 ° C -208 ° C 

4) The melting point of Sn-Zn solder wire is 117 ° C -119 ° C

5) The melting point of Sn-Cu solder wire is 220 ° C -222 ° C 

6) The melting point of Sn-Ag solder wire is 221 ° C


The above melting points of lead solder and lead-free solder are shared here. Note: In the red area, the temperature exceeds 400 ° C (752 ° F), do not often or continuously use; occasionally need to use in large solder joints or very fast welding It can only be used in a short time.