Analysis And Research On The Cracking Problem Of Chip Resistors After Assembling

"Reliability" is an important index of testing performance of space products,and the reliability of electronic components is the basis of the reliability of the whole equipment,which is one of the key factors for the success or failure of aerospace products.This paper is based on the Surface Mounted Devices resistor,and mainly studies the phenomena of cracking and falling off of glass glaze after assembly.On the one hand,the static structure of ANSYS Workbench is used to analyze the equivalent stress of patch resistance under different factors,and the preliminary analysis conclusion that paint layer thickness is the key factor.This paper analyze and put forward corresponding improvement measures from the four aspects: mechanical stress,curing stress,thermal stress and over-electrical stress,step by step in combination with the specific process of electronic assembly of products.On the other hand,the coating process of S113 polyurethane adhesive and Parylene high polymer are studied based on the conformal coating materials of patch resistance.And the corresponding test pieces are made to verify that it can effectively solve the crack problem of SMT resistor after mounting in the corresponding environment tests.The related research results have a good application prospect and technology reference value,which are helpful to improve product reliability.