What is the difference between Dewetting and non-wetting?

What is the difference between Dewetting and non-wetting?

According to the IPC standard, non-wetting is defined as the inability of molten solder to form a metallic bond with the base metal. Dewetting usually refers to alloy solder joints that are not extended to PCB pads, so they do not obtain a good solder joint fillet.

What causes Dewetting solder?

Dewetting in a solder joint indicates a problem with the solder pad or component part. Solder will not bond with the part. The two underlying reasons for this are corrosion and contamination, with subsequent overheating causing the dewetted condition.

What is solder webbing?

Solder mask webbing is the tiny, strip-like pieces of solder mask that remain in between the leads of any SMT part on an assembled PCB. Its purpose is to reduce the chances of solder bridging that may occur and would otherwise short circuit the component and potentially damage your board.

What does non-wetting mean?

(i) Example: ‘Total wetting’ vs. ‘ Non-wetting’ When a drop is placed down on very clean glass, it spreads completely. By contrast, the same drop deposited on a sheet of plastic remains stuck in its place.

What is non wetting in soldering?

Printed Circuit Board Nonwetting is a condition whereby a surface has contacted molten solder but has had part or none of the solder adhere to it. PCB Nonwetting is recognized by the fact that the base metal is visible. It is usually due to the presence of contamination on the surface to be soldered.

What is solder wettability?

Therefore, the ability of molten solders to wet or spread well over the metal surface is important for proper metallic bonding and is defined as wettability or spreadability.

How do you protect solder joints?

An electronic store like Radio Shack should carry it.

  1. Pick a diameter shrink wrap that is larger enough to cover the soldered connection and cut long enough to cover the bare wires.
  2. slip it on the wire pushing it far enough away from the connection to not be affected by the heat of the iron.
  3. wrap the wires together.