/Classification of welding defects during manufacturing process
The welding defects of the printed circuit board during the manufacturing process can be roughly classified into the following categories: poor wetting, poor gloss, improper solder amount, and poor cleaning.
What are the welding defects of printed circuit boards caused by poor wetting?
(1) poor lead wetting
(4) The solder does not fuse
What are the welding defects of printed circuit boards caused by poor gloss?
(1) solder paste icicles
(2) Solder joint bridging
(3) Solder joint overheating
What are the welding defects of printed circuit boards caused by too little solder?
(1) The solder does not fuse
(2) Solder joints into a spherical surfacing
(3) Solder joint bridge connection
(4) solder paste icicles
What are the welding defects of printed circuit boards caused by poor cleaning?
(1) The appearance of the board is a lot of dirt
(2) flux residue
(3) solder flow
(4) Circuit board discoloration
(5) flux splash
Take the poor wetting as an example. There are many reasons for the poor wetting. First, we must understand the storage period, status, production lot number and surface treatment conditions of the components to be welded. This poor wetting is mostly caused by the unmature skill of the operator.Some are caused by improper management of the welding tools, such as defects caused by wear of the tip of solder iron or defects caused by excessively high temperature of the solder iron.
① Prepare a actual product surface soldered pcb assembly board . Because printed solder paste and the PCB assembly board without soldering cannot fix the test end of the thermocouple, it is necessary to use the soldered actual product for testing. In addition, the test sample cannot be used repea...
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