Solder wire is one of the indispensable accessories in the welding of electronic products. It can be divided into lead-free solder wire and leaded solder wire according to whether it is environmentally friendly. The lead content is a small amount, less than 1000PBM meets the ROHS environmental protection standard, and the content of tin in the alloy composition is relatively high, as well as other metal elements such as silver and copper. Lead-free solder wire can also be divided into conventional environmental protection solder wire, nickel-plated environmental protection solder wire, stainless steel environmental protection solder wire, silver-containing environmental protection solder wire, etc., according to different functions, what are the differences between conventional environmental protection solder wire and silver-containing solder wire:

First, the melting point between the two is different: due to the difference in the metal alloy, the melting point is also different. Conventional environmental protection solder wire alloy Sn99.3Cu0.7, silver-containing environmental protection solder wire commonly used alloy ratios are Sn99Ag0.3Cu0.7 and Sn96.5Ag3Cu0.5; silver-containing environmental protection solder wire melting point is 217 degrees, while the conventional environmental protection solder wire The melting point is 227 degrees, and the melting point of the two is basically about 10 degrees different.

Second, the metal composition is different: the silver-containing environmentally friendly solder wire is composed of tin-silver-copper alloy, while the conventional environmentally-friendly solder wire is composed of the main alloy of tin and copper, and does not contain silver metal components.

3. Different cost: Due to the high price of silver metal, the cost of silver-containing environmentally friendly solder wire is more expensive than that of conventional environmentally friendly solder wire. This is the biggest advantage of conventional environmentally friendly solder wire, and its application is more extensive. The higher the silver content in the silver-containing lead-free solder wire, the more expensive the cost.

Fourth, the comprehensive performance is different: due to the action of silver metal, the silver-containing lead-free solder wire is better and stronger than the lead-free solder wire, and the solder joints are firmer. Secondly, electrical conductivity is also an important indicator in solder joints. Silver is a metal with good electrical conductivity, so lead-free solder wire containing silver has better electrical conductivity and thermal conductivity than lead-free solder wire. These properties are unsurpassed by lead-free solder wire.

5. The luster color of solder joints is different: the luster of lead-free solder wire shows a certain brightness, and the appearance is better; and silver-containing environmentally friendly solder wire is a matte metal, not a bright metal, so it contains silver The luster of lead-free solder wire is not bright and matte; however, the luster color of the solder joint does not represent the welding performance of the solder joint itself.