Understanding Soldering Iron Tips
HAKKO Soldering iron tips are made with a copper core for good thermal conductivity and plated with iron to prevent corrosion. The top of the soldering tip is tinned, or plated with solder, to allow for soldering, while the other areas are plated with chrome in order to prevent them from being wet with solder.
This applies to all soldering irons except for RED, U, PORTABLE, MATCHLESS, JUNIOR.
Over time, long and extended use of the soldering tip with no proper care can lead to the tip being worn out. This makes the soldering tip no longer suitable for use.
Let us explore the various ways in which a soldering tip can be worn out and how we can prevent that.
Corrosion of Iron Plating
Solder can corrode the iron plating when the iron (Fe) forms an alloy with the tin (Sn) from the solder itself and melts into the solder. This phenomenon is common when using lead-free solder or setting at higher tip temperatures, and becomes especially marked at temperatures exceeding 400ºC. When this happens, kindly dispose of the corroded tip and replace it with a new one.
By keeping the temperature of your soldering iron at its lowest required setting, it prevents the corrosion of the tip and increases the lifespan of your soldering tip.
How to solder at low temperatures with lead-free solder
Oxidation of Soldering Tip
Oxidation is easily identified with a blackened tip that no longer melts solder at the usual temperature. It happens when the iron plating beneath the solder-plated part becomes exposed to air, reacting with the oxygen to become oxidized and turning the area dark/black.
This is especially common when using lead-free solder, when the heat is too high, or the soldering iron is used without applying solder in the rework for solder bridge or other process.
Oxidation of Heating Element
Apart from the soldering tip, there are other portions of the soldering iron that are prone to oxidation. This includes the insert pipe, the tip enclosure, and the heating element inside the tip. The oxidation of any of these parts could lead to poor heat conduction, resulting in a higher temperature required for soldering. This in turn results in quicker oxidation of the soldering tip itself.
If any of the insert pipe, tip enclosure or heating element oxidizes, they should be replaced immediately with new ones.