Soldering Glossary of Terms

A mixture of two or more elements (usually metallic) that have properties differing from the pure elements.

A soldering defect where excess solder creates an unintended connection between two adjacent conductors or terminals

A poor solder joint that results from insufficient heat or improper soldering technique. Often, repeated reheating of a joint without additional flux will cause this.

The process of removing solder from a joint, usually to repair or correct an error.

A device which removes molten solder from a joint by a vacuum action.

A material usually made from fine copper wire woven together which when placed on a solder joint and heated, removes molten solder from the joint by capillary action. It usually has flux pre-applied to the braid.

An intermediate/advanced technique used to solder multiple closely spaced pins, typically on surface-mount devices (SMDs), in one continuous motion. This method is particularly effective for components like ICs (integrated circuits) with many pins and is faster than soldering each pin individually. Solder is fed into the iron as it is moved. The direction of movement is usually perpendicular to the axis of the leads on the SMDs.

The lowest melting alloy composed of two (or occasionally more) metals. It usually has a definite melting point and no paste phase.

A connector usually found on larger discrete components that has a tab with a hole in it. The hole is meant to have wire placed through it, and partially wrapped around the tab and soldered.

When a solder melts and is drawn into or over a solder joint.

In soldering, a chemical cleaning agent which helps to clean the soldering surfaces. It is normally activated by heat and by removing surface oxides greatly aids the formation of a good solder joint.

Rosin, Resin, Organic*, Inorganic*

(*generally water soluble and fairly active)

Flux serves two purposes it removes the oxide layer found on the metals in the joint, and it flows over the joint to prevent the formation of another oxide layer when the joint is heated.

A type of lead found on SMDs which is soldered to pads on the surface of the PCB. These leads are shaped with a gentle s-curve to allow the device to be raised slightly form the PCB surface.

A device or component used to absorb and dissipate heat away from sensitive components during soldering. It is usually used on components with leads and clamps to the leads.

The connection point where two or more pieces are soldered together.

A type of lead configurationfound generally on a SMD which is shaped like the letter J. The lead exits the body of the component downward and then curls under the SMD forming the "J" shape. The pads that it is soldered to are under the component.

A soldering alloy which contains very little to no lead at all.

A small metal area on a PCB to which components are soldered.

A non-conductive board used in electronics to connect electronic components using conductive pathways applied to or created on it. It is called "printed" because the conductive pathways are on the surface (like printing).

A technique used on surface mount devices with gull wing leads. It is similar to drag soldering except the movement of the iron is parallel to the long axis of the lead.

A process where solder paste is melted to create solder joints on a PCB, typically used for SMT.

Acronym referring to an act first passed in 2003 by the EU parliament calling for the reduction of hazardous substances in electronic devices. Lead containing solder was a material targeted in particular.

A fusible metal alloy used to join together metal workpieces. Generally divided into lead-free and leaded solders, the lead free alloys generally have higher melting points and a harder time with wetting. Leaded solder is easier to use but brings the toxicity of lead into the balance.

A mixture of solder and flux used in surface-mount soldering. The solder is in the form of very tiny spheres, that is practically a powder in the finer grades.

Solder alloy formed into a wire for easy application to a joint, usually by hand.

A protective coating applied to the PCB to prevent solder from bridging between conductors. Solder won’t adhere to it.

A hand tool used to heat solder and the joint, allowing the solder to flow into the joint.

A device that provides adjustable temperature control for a soldering iron.

An electronic component which is mounted to a PCB by being soldered to pads on the surface, rather than having leads which pass through to the opposite side of the PCB.

A method of mounting components directly onto the surface of a PCB, without using holes.

A method of mounting components by inserting leads through holes in a PCB and soldering them in place.

A common component of most solders, and the major component of most lead free solders.

The process of coating a soldering iron tip with solder to improve heat transfer and prolong the life of the tip.

The part of the soldering iron that transfers heat to the solder and components. Often replaceable, and made in various sizes and shapes to aid in soldering.

A method where a PCB is passed over a wave of molten solder to attach components. Used mainly with through-hole technology.

The property of a solder to spread onto a surface and coat it.

The process where solder is absorbed by a braid or wick to remove it from a joint.

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