Generally, the high-rise plate is a system plate, which is thicker, heavier and larger than the conventional multi-layer plate. The corresponding heat capacity is also larger. When welding, more heat is needed, and the welding high temperature time experienced is longer. At 217 ℃ (melting point of tin silver copper solder) it takes 50 seconds to 90 seconds. At the same time, the cooling speed of high-rise board is relatively slow, so the time of over reflow welding test is extended. Combined with ipc-6012c, IPC-TM-650 standards and industry requirements, the main reliability test of high-rise board is carried out
Oct 25, 2019
