How To Solve The Problem Of PCBA Processing Welding Porosity

Publish Time: January 05,2019

Generally, reflow soldering and wave soldering during PCBA processing will generate air holes, so how to solve the problem of PCBA board welding air holes? PCBA processing factory TECOO will explain to you in detail.

1. Bake

Bake PCBs and components that have been exposed to air for a long time to prevent moisture.

2. Control of solder paste

When the solder paste contains water, it is also easy to generate pores and tin beads. First of all, choose good quality solder paste. The temperature recovery and stirring of the solder paste are strictly implemented according to the operation. The solder paste is exposed to the air as short as possible. After the solder paste is printed, it needs to be reflowed in time.

3. Humidity control in the workshop

Monitor the humidity of the workshop in a planned way and control it between 40-60%.

4. Set a reasonable furnace temperature curve

Carry out the furnace temperature test twice a day to optimize the furnace temperature curve, and the heating rate cannot be too fast.

5. Flux spraying

In over-wave soldering, the amount of flux should not be too much, and the spraying is reasonable.

6. Optimize furnace temperature curve

The temperature of the preheating zone must meet the requirements, it can't be too low, so that the flux can fully evaporate, and the speed of the furnace can not be too fast. There may be many factors that affect PCBA soldering bubbles, which can be analyzed from the aspects of PCB design, PCB humidity, furnace temperature, flux (spray size), chain speed, tin wave height, solder composition, etc. It takes a lot of debugging to get a better process.