SMT X-ray inspection NDT Non Destructive Testing

There are cases of insufficient solder and solder short in BGA soldering, but it is also possible. Because the PCB BGA board has too much gap due to heat shrinkage (CTE), the edge of the BGA board is upturned. The smile curve is formed, and the circuit board is too long due to TAL (Time Above Liquidus), and the temperature difference between the upper and lower furnaces of the reflow furnace is too large, and the two-phase interaction forms a circuit board to bend down，Caused the so-called cry curve. If the cry curve, smile curve is severely deformed, short-circuit and air-welding of the BGA will be formed at the same time, which is usually the case when both occur at the same time. The picture shows that the BGA smile curve and the cry curve on the printed circuit board strongly squeeze the BGA solder balls, causing several short circuits. In general, consider reducing the slope of the reflow oven, either by preheating the BGA to eliminate thermal stress, or by requir...

AOI & X-ray Inspection Equipment Advantages AOI (Auto Optical Inspection), It has been widely used in the circuit board assembly line of the electronics industry, and has replaced the previous manual visual inspection operations. AOI uses imaging technology, to determine whether the object under test conforms to the standard based on whether there is a large difference, between the object to be measured and the standard image. Now and In the past Of AOI Before, AOI was used to detect whether the surface printing of the IC (integrated circuit) package was defective. As the technology evolved, Now it was used to detect the PCB assembly on the quality status of SMT assembly line, or check whether the solder paste meets the standards after printing. The biggest advantage of AOI is that it can replace the manual visual inspection before and after  SMT reflow soldering , and it can judge the shortcomings of SMT assembly assembly more accurately than the huma...