Basic requirements for solder joints

Date：2021-12-09 14:35:40Views：2208

Welding is a process in which the material of the workpiece to be welded (the same or different) is heated, pressurized or both, and whether to use filler materials is selected to make the material of the workpiece achieve the combination between atoms and form a permanent connection. Solder is an essential material for the welding electronics industry. The main solder materials include solder wire, solder strip, etc. What are the basic requirements of these solder materials for solder joints? Let's introduce them to you.

What is soldering?

Soldering refers to the metal bonding of components and printed circuit boards with solder at a melting point of less than 450 ℃. The tin in the molten solder is fused with the copper on the printed circuit board to form an alloy at the joint to realize welding.

Lead accounted for about 40% (tin 63% / lead 37%) of the solder used in the past (eutectic solder / lead containing solder). However, lead-free solder has become popular in recent years because lead will cause a great burden on the environment in the process of industrial emission. Lead free solder needs to increase the welding temperature by about 30 ℃, and the wettability is slightly poor, so the difficulty of welding is also improved.

Basic requirements for solder joints:

1. It has good conductivity: that is, the solder and the surface of the metal to be welded diffuse each other to form an alloy;

2. Have certain strength: that is, the solder joint must have certain tensile strength and impact toughness;

3. The amount of solder shall be appropriate: too little mechanical strength is low, which is easy to cause false welding, too much will waste solder, cause solder joint collision and cover up welding defects;

4. The surface of solder joint shall have good luster;

5. The welding spot shall be free of burrs, voids and bubbles;

6. The surface of the solder joint shall be clean, and there are residues or dirt, which will bring hidden dangers to the solder joint.

Work steps during welding:

1. Material preparation:

Heat the electric soldering iron to the working temperature, keep the soldering iron head clean and eat tin well, hold the electric soldering iron in one hand and solder wire in the other hand;

2. Heating:

The soldering iron head should contact the welded piece for about 1 second to 2 seconds;

3. Solder wire:

Contact with the solder joint of the workpiece, melt and wet the solder joint;

4. Remove the solder wire:

Generally, it is better to have uniform solder and fully wet the whole solder joint;

5. Remove the soldering iron:

Generally, evacuate at an angle of 45 degrees and rotate slightly to remove excess solder. Check the quality of welding joints and repair welding in time;

The above is the related content of "solder welding" brought by the core detection. Through this article, I hope it can be helpful to you. If you like this article, you might as well continue to pay attention to our website, and we will bring more wonderful content later. If you have any needs related to the inspection and testing of electronic products, please call Chuangxin testing, and we will serve you wholeheartedly.