What are the reasons for burrs, sharp edges or dirt on the edges after soldering with lead-free solder paste?

UseLead-free solder pasteWhat are the reasons for burrs, sharp points or dirt on the edges after welding? Nowadays, many manufacturers are asking why they are using itSMTWelding can lead to this phenomenon. Why does this occur? How to solve this situation? What causes this situation to happen? How to avoid this incident? Now, JJY solder Paste Manufacturer will explain this situation to you:

PCBThe formation of the board after soldering is blurry, the edge of the solder paste is uneven, and there are burrs on the surface.

1One possible situation is that the selected lead-free solder paste steel mesh has a rough and uneven wall, resulting in burrs and sharp edges on the circuit board after soldering.

Solution:SMTThe engineers from the manufacturer can conduct an inspection after cleaning and it can pass100Use a magnifying glass with a light source to inspect whether the hole walls of the stainless steel formwork are polished and the degree of polishing.

2,PABThe coating on it is too thick and the hot air leveling is poor, resulting in unevenness.

Solution: RequirementPCBThe manufacturer has improved and adopted gold plating.OSPWait for the pad coating process.

3It could also be a quality issue with the product itself. This aspect needs to be checked more.

Solution: You can communicate with the solder paste manufacturer to replace it with a product of higher viscosity, or check whether there is a quality issue with the solder paste.

Lead-free solder paste soldering tip:

1The circuit board with printing errors leads to insufficient cleaning of the circuit board.

Solution:SMTAfter the manufacturer uses lead-free solder paste for printing, if any misprints or missed prints are found, the entire circuit board must be thoroughly cleaned and reprinted. After cleaning the circuit board, it is essential to dry it with a hot air gun because many substances will stick to the gaps inside the circuit board and are invisible to the naked eye. Through the above steps, lead-free solder paste manufacturers believeSMTThe defects of burrs and sharp points in welding will definitely be greatly reduced.

2The bottom of the steel mesh is not clean and is stained with solder paste.

Solution: You can check if the back of the stainless steel formwork is not cleaned properly? Is there still a small amount of lead-free solder paste at the bottom of the steel mesh? If the phenomenon of garbage burrs is caused by incomplete cleaning, the stainless steel formwork can be removed for cleaning, and the frequency of cleaning and bottom cleaning can be appropriately increased.

Summary:

With the development of technology, more and more electronic processes require products in this area, so there are problems with performance parameters such as solder paste viscosity. There is a problem with the demolding parameter setting when the circuit board is separated from the screen printing board. The hole walls of the perforated screen plate have burrs. If you want to know more about raw tea andSMTCraftsmanship. Welcome to inquireJJY Technology Co., LTD!