Simulation Analysis For The Influence Of Pin Size Of QFP Device On Solder Joint Reliability

With the rapid development of electronic packaging industry,product reliability has become one of the important research topics.According to statistics,in the failure of electronic products,50% is caused by the welding fault between components and printed circuit boards,so the life of welding directly affects the service life of products.In the working environment of electronic packaging products,the impact of temperature and vibration on the life is more significant.In this paper,the response analysis and life prediction of QFP electronic packaging structures were carried out under the conditions of thermal cycling,random vibration and impact loading.The specific research contents are as follows:1.QFP electronic package structure is taken as the research object,and the whole board model of the circuit board is assumed and simplified.The Solid Works/ANSYS Workbench data interface was used to complete the CAD/CAE transformation of the model,and the grid independence was verified according to the specification standard of saturated mode number to obtain the finite element model of computer circuit board with saturated mode number.2.Under thermal cyclic loading,Anand viscoplastic unified constitutive model is selected to describe the thermodynamic properties of 63Sn37 Pb solder joints.ANSYS Workbench was used for thermodynamic analysis to obtain the distribution of stress and strain and the dynamic change rule of response of solder joint in the thermal cycle process,and to determine the dangerous parts of computer circuit board under the thermal cycle load.3.Under the loading of random vibration,the inherent characteristics of the structure are obtained through modal analysis,and the random vibration analysis is carried out to determine the dangerous parts of the computer circuit board under the loading of random vibration.The Steinberg model based on Gaussian distribution was selected to predict the vibration fatigue life of the two hazardous locations based on Manson's empirical high cycle fatigue relationship and the linear fatigue damage accumulation criterion.4.Conduct acceleration response analysis under impact load to determine the dangerous parts of computer circuit board under random vibration load.5.By comparing and analyzing the influence of lead shoulder width,straight lap length and station height of pin size on the reliability of QFP solder joint,the optimal pin size parameters were concluded.The research can provide some reference for the design and technology of board-level electronic packaging products.