What Are The Types of PCB Surface Treatment Tin Spraying

PCB tin spraying, also called “hot air leveling”, is an important process in the production of PCB boards. PCB board tin spraying mainly includes lead tin spraying and lead-free tin spraying. These two types of processes are commonly used. Let’s share the characteristics and basic knowledge of PCB spray tin type below.

 

PCB Surface Treatment Spray Tin Characteristics:

 

Tin spraying is the most commonly used process in PCB boards. This process is more practical. It has good soldering performance, good oxidation resistance, and the price is relatively affordable. It is a very cost-effective process. The PCB circuit board spray tin also has two distinctions between lead and lead-free.

 

PCB Surface Treatment Spray Tin Type:

 

1. Lead Spray Tin

 

The so-called lead-sprayed tin refers to the tin in a certain proportion, and the lead will increase the activity of the tin wire during the soldering process. The lead-tin wire is better than the lead-free tin wire, but lead is poisonous and contains lead. The lead is harmful to the human body. The eutectic temperature of lead is lower than that of lead-free. The quantity depends on the composition of the lead-free alloy. For example, the eutectic of SNAGCU is 217 degrees, and the welding temperature is the eutectic temperature plus 30-50 degrees. It depends on actual adjustments. The leaded eutectic is 183 degrees. Lead is better than lead-free in mechanical strength and brightness. Therefore, it is not environmentally friendly to have lead and tin, and it is somewhat different from the environmental protection advocated by the world. Therefore, lead-free tin spray was born.

 

2. Lead-Free Tin Spray

 

Lead-free tin is an environmentally friendly process. It has very little harm to the human body. It is also a process advocated at this stage. The content of lead in lead-free tin does not exceed 0.5. Lead-free tin has a high melting point, so that the solder joints are much more firm. In essence, lead spray tin and lead-free tin spray are a process. It’s just that the purity of lead is different. Lead-free tin is more environmentally friendly and safer for the human body, and it is also a future development trend. It is recommended that you use it.

 

Introduced the characteristics and shortcomings of the two process types, lead spray tin and lead-free tin spray. Among them, lead spray tin is easier to use, but it is not safe, environmentally friendly, and harmful to the human body, so lead-free tin spraying is recommended which  is non-toxic and harmless, and it is also a surface treatment process that is currently advocated.

 

XPCB Limited is a manufacturer specializing in the production of high-precision double-sided, multi-layer and impedance, blind buried vias, and thick copper circuit boards. The products cover HDI, thick copper, backplanes, rigid-flex combined, buried capacitance and buried resistance, Golden Finger and other kinds of circuit boards, which can meet the needs of customers for all kinds of products.