Soldering Technology of Electronic Components
Soldering is actually the easiest way to connect components with high quality. Therefore, welding technology is quite necessary. Recommendation: How to use a soldering iron?
1. Tools:
Commonly used tools and materials for welding: electric soldering iron, solder, flux, wire cutters, multimeter, etc. are all necessary tools.
1. Soldering iron
The electric soldering iron is the most commonly used tool in welding. Its function is to convert electrical energy into heat energy to heat and weld the soldering point.
The greater the power of the electric soldering iron, the greater the heat, and the higher the temperature of the soldering iron tip.
Generally, a 20W internal heating type electric soldering iron is enough. If the power is too high, it is easy to burn out the components. Generally, the junction temperature of diodes and triodes will burn out if the junction temperature exceeds 200°C.
Note that when soldering, the time should not be too long or too short. If the time is too long, it will be easily damaged. If the time is too short, the solder will not be fully melted, causing the solder joints to be not smooth and firm, and may also cause virtual soldering. Generally, the most appropriate must be in the Complete within 1.5-4s.
2. Solder
Solder is a fusible metal, and the most commonly used one is generally tin wire. The role of solder is to connect the component pins with the connection points of the printed circuit board. The choice of solder has a great influence on the soldering quality. The most commonly used one is generally tin wire.
3. Flux
There is no need to explain more about the flux, which can make the solder and components better welded. Generally, rosin is used the most.
Rosin flux
The solder suction device is very practical for novices. It is always easy to get the solder everywhere when using the electric soldering iron for the first time. The solder suction device can help you remove the excess solder on the circuit board. In addition, the solder suction device is very useful when removing components. It can suck all the solder joints, but it is completely unnecessary for those who can skillfully use a soldering iron. It can completely replace its function with a soldering iron to melt the solder joints. The components can be easily removed.
How to solder components:
Pre-welding treatment:
Before soldering, pre-soldering treatment should be performed on the component pins or the soldering parts of the circuit board.
Pre-weld treatment
1. Remove the oxide layer on the welding part
A knife can be made from a broken saw blade. Scrape off the oxide layer on the surface of the metal leads to expose the metallic luster of the leads.
The printed circuit board can be polished with fine gauze paper, and then coated with a layer of rosin alcohol solution.
2. Component tin plating
Tin on scraped leads. After dipping the lead wire in the rosin alcohol solution, press the tip of the hot soldering iron with tin on the lead wire and turn the lead wire. The leads can be evenly plated with a very thin layer of tin. Before the wire is welded, the insulation sheath should be peeled off, and then the above two treatments can be performed before formal welding. In the case of multi-strand wires, they should be twisted together after polishing, and then tinned.
After the pre-welding treatment is done, the welding can be officially carried out.
(1) Hold the electric soldering iron in the right hand. Use needle-nose pliers or tweezers with your left hand to hold components or wires. Before soldering, the electric soldering iron should be fully preheated. Tin should be eaten on the blade surface of the soldering iron head, that is, a certain amount of solder should be brought on.
(2) Place the blade of the soldering iron tip against the solder joint. The electric soldering iron is at an angle of about 60° to the horizontal plane. To facilitate the flow of molten tin from the tip of the soldering iron to the solder joint. The time the soldering iron tip stays at the solder joint is controlled within 2 to 3 seconds.
(3) Lift the tip of the soldering iron. The left hand still holds the component. The left hand can only be released after the tin at the solder joint is cooled and solidified.
(4) Rotate the lead wire with tweezers to confirm that it is not loose, and then use the pliers to cut off the excess lead wire.
