How do you inspect a solder joint?
EXAMINING THE SURFACE OF THE JOINT Clues to the quality of this joint include its texture, uniformity, smoothness, color and brightness and surface characteristics. A poor solder joint with micro cracks on its surface could be “seen” with the endoscopic inspection tool but would not show up on XRAY.
What are the signs of a good quality soldered joint?
What Constitutes Good SMT Solder Joint Quality?
- component pin and footprint pad are aligned;
- pad area is completely covered with solder;
- component pin area in contact with pad is completely covered with solder;
- no excess solder covers component;
- solder joint is smooth;
- solder joint does not contain voids; and.
How can you tell if you have a bad soldering joint?
A cold solder joint occurs when the solder does not melt completely. A result of insufficient heat, cold joints are often characterized by being rigid, rough, and uneven in appearance. This solder mistake creates an unreliable joint that is highly susceptible to cracking and failure.
What precautions must be taken to avoid a cold solder joint?
Cold joints frequently have excess solder which you can draw off with the soldering iron tip. You can prevent cold solder joints by giving your soldering iron sufficient power and time to warm up. An overheated joint results from solder failing to flow and the burnt flux residue can make repair very difficult.
How do you inspect a solder joint BGA?
X-ray inspection for BGA The BGA solder joint bonds are inspected using X-rays. The X-ray inspection helps to look through the device solder joint underneath the components. Due to this ability, the Automated X-ray Inspection (AXI) technology is widely used for BGA inspection.
What are three common causes of a poor solder joint?
Top 5 Reasons for Solder Joint Failure
- Unintended Stresses from Potting, Underfills and Conformal Coatings.
- Unexpected Temperature Cycling Extremes.
- Mechanical Overstress Events.
What should a good solder look like?
A proper solder joint is smooth, shiny and looks like a volcano or cone shape. You want just enough solder to cover the entire joint but not too much so it becomes a ball or spills to a nearby lead or joint.
Why do solder joints fail?
The only way a joint can fail is if it is not made properly, whether it is because the solder did not flow properly or the pipe was not inserted all the way into a fitting. It has nothing to do with turbulence because the solder does not interact with the liquid flow.
What is the best advice for soldering components?
How to Solder
- Never touch the element or tip of the soldering iron.
- Take great care to avoid touching the mains flex with the tip of the iron.
- Always return the soldering iron to its stand when not in use.
- Work in a well-ventilated area.
- Wash your hands after using solder.
How are good and cold solder joints evaluated?
Cold solder joints can be detected by visual checking or using a magnifying glass. Primarily, a cold solder joint could look dull, whitish, and convex, or deformed, which is very different from a proper solder joint. Another way to detect a cold solder joint is by using a Multimeter.
Why is BGA used?
A ball grid array (BGA) is a type of surface-mount packaging (a chip carrier) used for integrated circuits. BGA packages are used to permanently mount devices such as microprocessors. A BGA can provide more interconnection pins than can be put on a dual in-line or flat package.
What is BGA package?
B. G. (Ball Grid Array) A popular surface mount chip package that uses a grid of solder balls as its connectors. Available in plastic and ceramic varieties, BGA is noted for its compact size, high lead count and low inductance, which allows lower voltages to be used.