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What is the difference between lead-free tin and lead-spray tin on pcb boards?

2019-08-22 16:28:53 442

Pcb board What is lead-free tin spray? What is lead-spray tin? What is the difference between lead-free spray and lead spray?


The process requirement in the production of pcb circuit board is a very important factor. He directly determines the quality and positioning of a board. The following is introduced by (Juding Circuit Technology): PCB lead-free tin-plated tin and lead-spray tin Where is the difference?


For example, tin, gold, relatively speaking, Shen Jin is facing the high-end board. Because of its good quality, Shenjin is relatively high in cost, so many customers choose the most common tin-spraying process. Many people know the tin-spraying process, but they don't know that tin is also divided into lead-tin and lead-free tin.


1. From the surface of tin, lead tin is brighter, and lead-free tin (SAC) is dim. Lead-free infiltration is worse than lead.


2. Lead in lead is harmful to the human body, but not lead. The lead eutectic temperature is lower than that of lead-free. Specifically, it depends on the composition of the lead-free alloy. The eutectic like SNAGCU is 217 degrees, and the soldering temperature is eutectic temperature plus 30 to 50 degrees. It depends on the actual adjustment. The lead eutectic is 183 degrees. Lead in mechanical strength, brightness, etc. is better than lead-free.


3. The lead content of lead-free tin does not exceed 0.5, and lead has reached 37.


4, lead will improve the activity of the tin wire in the welding process, lead wire is relatively better than the lead-free tin wire, but lead is toxic, long-term use is not good for the human body, and lead-free tin will have a higher melting point than lead-tin. This makes the solder joints much stronger.


What is the difference between lead-free soldering and lead-spraying on PCB boards? What is the temperature?


1. PCB circuit board lead-free spray tin is environmentally friendly and contains no harmful substances "lead", melting point is about 218 degrees; tin soldering furnace temperature needs to be controlled at 280-300 degrees; over-peak temperature needs to be controlled at about 260 degrees; The reflux temperature is 260-270 degrees.


2, PCB circuit board lead spray tin is not environmentally friendly containing "lead" harmful substances, melting point of about 183 degrees; spray tin furnace temperature needs to be controlled at 245-260 degrees; over-peak temperature needs to be controlled at about 250 degrees; The reflux temperature is 245-255 degrees.


Shenzhen Juding Circuit Technology Co., Ltd. specializes in: PCB circuit board manufacturing, PCB board proofing, HDI board, TG board, mixed pressure board, thick copper foil board, impedance board, Rogers board, soft and hard board, metal substrate, etc. A special material or process PCB board 1-34 laminate production and production. Welcome to consult customers for more details!