SMD materials tend to absorb moisture. If the materials, after resoldering, absorb moisture, it will have little effect on performance. But if the SMD materials absorb moisture before resoldering, it will cause serious defects. During the resoldering process, the moisture will turn into steam. This high-temperature steam will cause internal stress in the SMD material, causing damage to the internal structure of the SMD. Therefore, the SMD must be protected from moisture before resoldering.
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