How long does an electric soldering iron need to be heated
The 60W electric soldering iron has a high power, but it usually needs to be preheated for 3-5 minutes. Although you may seem to be getting hot and emitting white smoke, you may not have reached the melting point of the solder yet. The preheating time of an electric soldering iron is also related to the usage environment. In environments with high wind and low temperature, the preheating time will be longer. It is recommended to take some protective measures (such as adding a sleeve) for the electric soldering iron in low temperature and high wind environments to ensure that it can continue to accumulate heat and reach a certain high temperature.
The new electric soldering iron will have a slight smoke and odor when used for the first time. There is a layer of anti oxidation paint on the top of the soldering iron, which should be gently wiped off before use. For the first use, it is necessary to fully feed the soldering tin to the soldering iron head, so that it can be fully absorbed and welded.
Welding principle of electric soldering iron
Tin welding is a science, and the principle of electric soldering is to heat and melt the solid solder wire through a heated soldering iron. With the help of soldering flux, it flows into the metal to be welded and forms a solid and reliable welding point after cooling.
When the solder is made of tin lead alloy and the welding surface is made of copper, the solder first wets the welding surface. With the occurrence of wetting phenomenon, the solder slowly diffuses towards the metal copper, forming an adhesion layer on the contact surface between the solder and the metal copper, making the two firmly bonded. Therefore, soldering is accomplished through three physical and Chemical process: wetting, diffusion and metallurgy.
1. Wetting: The wetting process refers to the use of capillary force to diffuse the melted solder along the fine concave convex and crystalline gaps on the surface of the base metal, forming an adhesion layer on the surface of the welded base metal, making the solder and the atoms of the base metal close to each other, achieving the distance at which atomic gravity acts.
Environmental conditions that cause wetting: The surface of the welded base material must be clean and free from oxides or pollutants.
Image metaphor: Dropping water onto lotus leaves to form water droplets means that water cannot moisten the lotus. Drop water onto the cotton and it will penetrate into the cotton, which means that water can moisten the cotton.
2. Diffusion: With the wetting process, the mutual diffusion phenomenon between the solder and the base metal atoms begins to occur. Usually, atoms are in a thermal vibrational state in the lattice lattice, once the temperature increases. The intensification of atomic activity causes the atoms in the melted solder and base metal to cross the contact surface and enter the lattice of each other. The speed and number of atoms' movement depend on the heating temperature and time.
3. Metallurgical bonding: Due to the mutual diffusion between the solder and the base metal, an intermediate layer - a metal compound - is formed between the two metals. In order to obtain good solder joints, a metal compound must be formed between the welded base metal and the solder to achieve a strong metallurgical bonding state of the base metal.
