What Solder Is Used for Radiators?

The solders used for repairing leaks in radiators are typically alloys consisting of mostly lead, combined with tin. These alloys melt well for soldering. Also, lead is highly resistant to corrosion, while tin adds strength.

Considerations for Lead

Lead is a soft but very dense metal, according to the KeyToMetals website. It also flows and molds well. However, because of its softness, it is often alloyed with other metals. The addition of tin makes the alloy especially suitable for soldering radiators.

Considerations for Tin

The addition of tin to lead alloys enables the solder to bond with metals like steel. Alloys of lead and tin melt at lower temperatures than each would alone. Tin also adds hardness. Solders high in lead and lower in tin are effective for welding smooth joints and seams.

Other Facts

The solders usually have a content of about 20 to 35 percent tin, the remainder consisting of lead. Soldering is a common way of repairing leaks in radiators. Even minor leaks should be addressed immediately since they can quickly escalate into major problems, according to the Cars Direct website.

References

• Key to Metals: Tin and Tin Alloys
• Key to Metals: Lead and Lead Alloys
• CarsDirect: How to Solder for Radiator Repair