How do we clean
lead-free solder paste after soldering? Nowadays, this product is more and more widely used in the society, and when using this product, slag will appear when welding, or some problems are difficult to clean. In this case, how should we choose to avoid or clean it? There are more and more manufacturers of this product in the society, and most people don’t know how to choose. Let’s listen to some suggestions here:
Everyone knows that lead-free solder paste is a substance with very active chemical properties, so it has very strict requirements on the environment. Generally, the shelf life is 6 months at a temperature of 2~10°C and a temperature of about 20%. , After the soldering is completed, some impurities may remain on the PCB, so how to clean it off?
First of all, we need to know why we need to clean. After the lead-free solder paste is soldered, there will be more or less residues, and there are several types of residues:
1. Particulate pollutants can easily cause electrical short circuit;
2. Polar pollutants will cause dielectric breakdown, leakage and corrosion of component circuits;
3. Non-polar contaminants will affect the appearance, mainly by white powder and dust, and lead to poor electrical contact.
Secondly, although I realized that it needs to be cleaned, I used the wrong cleaning method, as follows:
1. When there is no ultrasonic wave, simply soak the circuit board and then take it out to dry.
2. Use a brush dipped in cleaning agent to scrub the circuit board a few times.
After the soldering is completed, some impurities may remain on the PCB, so how to clean it off?
So how should it be cleaned?
1. It should be cleaned as soon as possible after welding (within 1 hour);
2. Increase the preheating temperature of the cleaning agent;
3. Extend the cleaning time;
4. Replace with new cleaning agent frequently.
After cleaning, we'd better check again to see if it's really cleaned. The easiest way is to take a visual inspection and observe under a microscope.
When choosing a solder paste manufacturer, you should choose a product for your own products. At present, our lead-free solder paste and lead-free solder wire are widely used in the market, such as LED printing and bonding manufacturers, ultra-fine Nano-tin powder manufacturers need tin balls, and power capacitor manufacturers need special tin wires for the zinc surface of power capacitors. The effect after use is also very satisfactory.