Common Welding Defects inspected by X-ray
What are the common welding defects of X-ray? Common soldering defects mainly include the following: bridging, open soldering, insufficient tin, too much tin, poor alignment, voids, solder beads, missing components or pins, etc.
The solder joints of chip components The main common chip components are: chip resistors and chip capacitors. These components have only two solder ends, and the solder joint construction is relatively simple. Due to the different body materials of various chip components, the chip resistors can be completely penetrated under X-rays. Only the lead-tin solder joints at both ends can block X-rays; X-rays cannot penetrate the material, but it is impossible to wear a special substance near the cathode of a tantalum capacitor, so it can be judged whether the polarity of the tantalum capacitor is correct and whether the component is missing.
Common defects of chip components mainly include open soldering, solder beads, etc. Other defects are relatively few. Generally, these common defects are largely related to factors such as soldering temperature profile and pad design, and can be largely avoided as long as these common defects can be reasonably controlled.
There are two main types of wing-lead assemblies: QFP and SOIC. Except for the lead spacing, the solder joint images are the same for both types. Usually qualified solder joints should have sufficient solder height in the heel part. There should be good solder fillet in the middle of the bonding surface at the bottom of the lead. As for the solder on the ends of the leads, it is generally considered negligible as it has no significant effect on the strength of the solder joints. Based on the three parts of the solder and the length of the solder joint, the quality of the solder joint is again evaluated.
Shenzhen Baiqiancheng Electronics Co., Ltd. has 19 years of PCB processing experience, and has rich experience in quality management in the production process. X-rays are helpful for the detection of common bad problems in soldering of components, and we can quickly give solutions to ensure that the PCBA to customers is of high quality.
