Solder is a metal alloy used in joining two or more metal surfaces together through a process called soldering. It is typically a mixture of tin and lead, although other metals such as silver, copper, and zinc may also be used.

Solder is characterized by its melting point, which is lower than the melting points of the metals being joined. This allows the solder to melt and flow between the surfaces being joined, creating a strong bond as it cools and solidifies.

Solder comes in a variety of forms, including wire, paste, and preformed shapes such as bars and pellets. The type of solder used depends on the materials being joined and the application. For example, lead-free solder is often used in electronics applications due to concerns about the toxicity of lead.

In addition to its use in joining metals, solder may also be used in other applications such as creating electrical connections, sealing leaks in pipes, and forming decorative patterns on metal surfaces.




Here are some common types of solder:


Tin-lead solder: This is the most commonly used solder and is typically composed of 60% tin and 40% lead. It has a low melting point and is easy to work with.


Lead-free solder: This type of solder is composed of various combinations of metals such as tin, copper, and silver, and does not contain lead, which can be toxic. It has a higher melting point than tin-lead solder and requires more heat to melt.


Silver solder: This type of solder contains a high percentage of silver and is used for joining metals with high melting points, such as stainless steel. It requires a higher temperature to melt than other types of solder.


Flux-core solder: This type of solder contains flux inside the core, which helps to clean the metal surfaces being joined and promote good adhesion.


Acid-core solder: This type of solder contains acid flux inside the core, which can be used for plumbing applications to remove oxidation and other contaminants from the surfaces being joined.


Rosin-core solder: This type of solder contains rosin flux inside the core, which is less aggressive than acid flux and is commonly used in electronics applications.


Aluminum solder: This type of solder is designed specifically for joining aluminum and other non-ferrous metals, which can be difficult to solder using traditional methods.

The type of solder used depends on the materials being joined, the application, and any specific requirements such as lead-free or food-grade solder for plumbing applications. It's important to select the appropriate type of solder and to follow proper safety precautions when working with it.