What is required concerning visible residues for assemblies subjected to cleaning processes?

For assemblies that have undergone cleaning processes, it is necessary that they are free of visible residues. This requirement ensures that any contaminants, such as flux residues, dirt, or cleaning agents, do not negatively affect the assembly's performance or reliability. Visible residues can lead to issues like corrosion, electrical shorts, and reduced lifespan of the components due to potential overheating or other forms of failure.

The requirement for a clean assembly aligns with the standards set forth in J-STD-001, which emphasizes the importance of cleanliness in soldered electrical and electronic assemblies. Achieving and maintaining a residue-free condition is critical for ensuring the integrity and functionality of the assembly, as any residues present can compromise the effectiveness of the solder joints and overall assembly durability.