Abstract: After an instrument was placed at room temperature for a period of time, the interconnection between conductive adhesive and metal skeleton was poor. The failure causes were analyzed by means of macro observation, electrical property test, X-ray inspection, tensile strength test, scanning electron microscope and energy spectrum analysis. The results show that the poor varnish coating process of conductive adhesive of the instrument caused the corrosion of metal skeleton, and then weakened the bonding interface between conductive adhesive and metal skeleton. Under the action of external stress, it caused poor contact between conductive adhesive and skeleton.