In the PCBA manufacturing process, it is inevitable that there will be problems of one kind or another. Especially when the PCBA board is reflowed and wave soldered, the PCBA board will be deformed due to various factors, resulting in poor PCBA soldering. Today we will mainly introduce the main reasons for the PCBA board deformation.

The first one is the selection of PCB materials. With the popularity of lead-free technology, the furnace temperature is higher than that of lead, and the requirements for sheet materials are getting higher and higher. The circuit board of the plate with the lower TG value is easier to deform when passing the furnace, but generally speaking, the higher the TG value of the plate, the more expensive the price.

The second is the thickness of the PCBA board. With the development of electronic products in the direction of small and thin, the thickness of the circuit board is increasingly thin. It is precisely because of this that a thinner circuit board is more likely to be deformed due to high temperature during reflow soldering.

Third, PCBA board size and number of panels. When the circuit board is reflow soldered, it is generally placed on a chain for transmission. The chains on both sides are used as supporting points. If the size of the circuit board is too large or the number of panels is too large, it is easy to dent in the middle point and cause the circuit board to deform.

Fourth, the copper area on the PCBA board is uneven. Generally, a large area of copper foil is designed on the circuit board for grounding purposes. Sometimes there is also a large area of copper foil designed on the Vcc layer. When these large area copper foils cannot be evenly distributed on the same circuit board When it is installed, it will cause the problem of uneven heat absorption and heat dissipation. The circuit board will also expand and contract with heat. If the expansion and contraction cannot be performed at the same time, it will cause different stress and deformation. At this time, if the temperature of the board has reached At the upper limit of the TG value, the board will begin to soften, causing permanent deformation.

Fifth, PCBA board temperature. Each circuit board will have a maximum TG value. When the reflow soldering temperature is higher than the maximum TG value of the circuit board, it will cause the board to soften and cause deformation.

Sixth, the connection points of each layer on the PCBA board. Today's circuit boards are mostly multilayer boards with many drilled connection points. These connection points are divided into through holes, blind holes, and buried holes. These connection points will limit the effect of thermal expansion and contraction of the circuit board, thereby Lead to deformation of the board.

The above are the main reasons for PCBA board deformation. When PCBA processing and production are carried out, these reasons can be prevented, which can effectively reduce the deformation of PCBA board.