Analysis of PCBA Plate Deformation

PCBA board in the reflow soldering and wave soldering, due to various factors affect the PCBA board will be deformed, resulting in poor PCBA welding, which has become a headache for the production staff. Next for everyone to analyze the reasons for the deformation of PCBA board.

PCBA board

1, PCBA plate furnace temperature

Each circuit board will have the largest TG value, when the reflow temperature is too high, higher than the maximum TG value of the circuit board, will cause the board to soften, causing deformation.

2, PCB board

With the popular lead-free process, the furnace temperature is higher than the lead, the plate also requires more and more high. The lower the TG value of the board more easily in the furnace board deformation, but the higher the TG value, the more expensive the price.

3, PCBA board thickness

With the development of electronic products in the direction of small and thin, the thickness of the circuit board is also more and more the pursuit of thin, the thinner the thickness of the circuit board, in the reflow, the impact of high temperature more easily lead to deformation of the board.

4, PCBA board size and puzzle number

Circuit board in the reflow soldering, the general placed in the chain for transmission, both sides of the chain as a support point, the size of the circuit board is too large or too many puzzle, are easy to board to the middle point depression, resulting in deformation.

5, V-Cut depth

V-Cut will destroy the board structure, V-Cut in a large sheet of the original cut out the groove, V-Cut line too deep will lead to PCBA board deformation.

6, PCBA board on the uneven copper area

The general circuit board will be designed with a large area of copper foil as a ground use, and sometimes Vcc layer will also have a large area of copper foil design, when these large areas of copper can not evenly distributed in the same piece of circuit board On the time, it will cause the heat and heat dissipation of the uneven problem, the circuit board will certainly heat and shrink, if the rise and fall can not cause different stress and deformation, this time the board if the temperature has reached TG value of the upper limit, the board will begin to soften, resulting in permanent deformation.

7, printed circuit board assembly layers of the connection point

Today's circuit boards are mostly multilayer boards with a number of connection points, which are divided into through holes, blind holes, and buried points. These connections limit the thermal expansion and contraction of the circuit board, thus Leading to deformation of the board.

The above is the main cause of deformation of PCBA board, PCBA processing in the production, these can be a few reasons to prevent, can effectively reduce the deformation of PCBA board.