Failure Mode
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Poor solderability of input and output terminals
● When the microstrip circuit surface treatment process problems, resulting in solder at the input and output end is not wet, affect the welding quality.● Drop-in circuits of Drop-in devices are fabricated by machining beryllium bronze or brass and then electroplating. When the surface of the Drop-in oxidizes or gets scratched, it can lead to poor wetting of solder at the input and output terminals, affecting the quality of soldering.
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Open circuit in a resistor
● Isolators are manually soldered by joining the Drop-in circuit and resistors together. During abnormal production processes or under stress from temperature and mechanical factors, cracks or fractures may occur at the solder joints or leads of the resistors, resulting in an open circuit and abnormal electrical performance of the isolator. -
Cracks in ferrite substrate
● The microwave ferrite substrates used in microstrip devices are made of polycrystalline ferrite materials, which are brittle and have poor toughness. Under abnormal production processes and stress during use (such as temperature and mechanical stress), shallow surface cracks or through-cracks may appear on the substrate surface. When these cracks propagate to the surface thin-film circuit, it can result in abnormal electrical performance. -
Other failures
● Coating corrosion.● Hard scratches caused by improper testing.● Cracks in the Drop-in due to bending.