Everyone knows that the composition of solder wire is mainly composed of tin alloy and additives. The alloy components are divided into tin-lead and lead-free additives and are evenly poured into the middle part of the tin alloy. Although the main component of solder wire is tin, it also contains other metals. Mainly divided into lead and lead-free (ie environmentally friendly).
Lead is mainly composed of tin and lead in various proportions. An alloy composed of tin (melting point 232 degrees) and lead (melting point 327 degrees). Among them, the solder composed of 63% tin and 37% lead is called eutectic solder, and its melting point is 183 degrees.
Lead-free, in order to meet the ROHS standard proposed by EU environmental protection requirements. Mainly made of tin-copper, tin-silver-copper and other alloys.
The main practical difference between the two is the melting temperature. So in essence, you can choose any one you like.
Lead solder wire
Lead-based solder wires have been commonly used in the past. It is made of a mixture of tin and lead. It is usually a 60/40 (tin/lead) mixture, which melts at about 180-190 degrees Celsius.
As lead has some destructive effects on our health, the industry is gradually moving away from leaded solder wires.
Lead-free solder wire
Lead-free solder wire is lead-free solder. Due to the health hazards of lead, the European Union requires commercial electronic equipment to use lead-free solder wire (RHoS).
Product advantages of lead-free solder wire:
Good wettability, fast soldering speed, no splashing of rosin when soldering, uniform distribution of rosin in the wire, continuous core, low smoke, no odor, no volatile gas harmful to health, and less scum on the molten iron head , The tin wire will not be tangled when the wire is welded by the automatic soldering machine, does not block the conduit, the rosin is transparent, does not change color, the insulation resistance is high, low residue, and no cleaning.
Product categories of lead-free solder wire:
Rosin core tin wire, water-soluble tin wire, nickel-plated tin wire, low temperature tin wire, high temperature tin wire, silver tin wire, matte tin wire, solid tin wire, washed tin wire, solder aluminum tin wire, stainless steel tin wire, machine Tin wire for automatic welding, tin wire for speaker, tin wire for motor.
It has a higher melting point, so it is a bit difficult to use, but it is usually not a problem.
The solder wire generally has a core inside the solder wire containing flux. The flux aims to improve the electrical contact and mechanical strength of the solder joints.
There are mainly two types of magnetic flux cores. Acid core and rosin core. Acid cores are used for pipes and rosin cores are used for electronic equipment. So use rosin core
The melting point is also different: of course, according to the ratio of lead to tin in the solder wire. Because the melting point of leaded solder wire is about 180 degrees, the difference lies in their different melting points, which are also different according to the metal composition ratio. The melting point of lead-free solder wires is generally around 230 degrees.
The use of lead-free and leaded solder should also be considered in terms of environmental protection. Lead is a toxic metal. Higher purity tin will cause tin whisker growth, and has a fixed melting point (176°C) rather than a temperature range, such as tin and antimony. Alloy. 9℃. The tools and components used must be lead-free.
Lead-free solder is basically lead-free (the EU ROHS standard is that the lead content is less than 1000PPM: Lead-free solder will leave black marks on the hand, because lead-free generally contains copper. The difference between lead-free solder and lead-free solder is as follows : Sn63Pb37, the Japanese standard is less than 500PPM).
To sum up: Lead solder wire has a low melting point and is cheap, but it is harmful to human health.
Lead-free solder wire has a high melting point and is environmentally friendly. Buy lead-free solder wire