Soldering is the process of joining metals by means of alloys that melt between 170ºC-370ºC. The strength of the joint depends on the chemical composition and cleanliness of the surfaces to be joined.

Soldering produces liquid and gas tight joints quickly and at low cost. Most soldering applications are carried out in air, with the flux acting as a barrier to surface oxidation and interaction with the atmosphere. It is a convenient and economical way to produce joints when more complex joining machines are not available or cost-effective.

Solid state induction heating is very well suited for soldering applications in a production environment. Heat can be applied to specific regions of a part in a very controlled and precise manner. Induction heating is well suited for production line applications because of low time-to-temperature, high levels of repeatability and non-contact, clean heating.

Typical power supplies for soldering range from 1 to 50 kW, depending on part and process requirements.

• Soldering A Car Radio Antenna
• Soldering Flexible Electrical Circuits
• Soldering Flexible Connector Circuits
• Soldering Steel Connectors To A Brass Block
• Soldering A Brass Slip Ring To A Copper Wire Assembly
• Soldering A Brass Bellows End Cap Assembly
• Soldering Copper Tubing For An Ice Machine Evaporator Assembly
• Soldering A Cellular Phone Antenna

Flux is applied first to the bonding surfaces and then heat is applied to the joint area. The temperature required is just above the melting point of the solder. The solder is allowed to flow in the joint. After re-flow, the solder is allowed to cool naturally and re-solidify.

Metal: Iron, nickel, copper, lead, tin, zinc, aluminum

Solder : Generally lead and tin alloys·
Flux : Necessary to rid the surface of the metals to be joined of oxides, to promote wetting and obtain intimate contact between the solder and base metal. There are different forms of flux: corrosive, intermediate and non-corrosive.

Corrosive (Acid) flux cleans the surface well and is good for copper, low carbon steel, brass and bronze soldering. However, it is difficult to clean off after the process. Intermediate fluxes contain organic compounds and decompose at soldering temperatures. They are suitable for all materials that are solderable with mild fluxes. Non-corrosive fluxes are rosin-based. They are a good choice for electronic and critical soldering applications.

Heat source : fast, precise heating is best.

• Low unit strength.
• Little resistance to fatigue
• Limited to service temperatures below 150ºC.

Tricks Of The Trade

Cleanliness of the joint surfaces is critical. Both metal surfaces that are to be joined need to come to temperature at the same time.

If the temperature is too high, a strong joint cannot be created. Instead of stick-feeding the solder, use a paste or pre-form solder that is placed in the joint areas before heating