Research On The Effects Of Insertion-extraction On The Contact Performance Degradation Of Electrical Connector

As a basic component,electrical connector is used for the transmission and control of electrical signals in model system with large amounts and plays an important role.In order to meet the increasing reliability requirements of the system,the storage life requirement of electrical connector has reached 20~30 years.At present,when evaluating the storage life of electrical connectors,the influence of temperature on the performance degradation is mainly considered.However,the insertion-extraction during test has not been taken into account.The dissertation takes the commonly used Y11P-1419 electrical connector as the research object,based on the analysis of the storage environment effect and failure mechanism of electrical connector,and reveals the effect of insertion-extraction on the degradation performance of electrical connector through accelerated degradation test,and evaluates the storage reliability and storage life of the electrical connector considering insertion-extraction by the experimental data,thus providing a basis for further research.This dissertation is composed of five chapters,and the main work of each chapter is specified as follows.Chapter 1 describes the background and discusses the significance of this research.In this chapter,the domestic and foreign research status and the remaining problems in storage reliability,the accelerated degradation test technology and the storage reliability of electrical connectors are proposed.Besides,the research object and the main research content are proposed.In chapter 2,the thesis first summarizes the structure,type and function requirements of the commonly used electrical connectors.Based on the analysis of the storage environment effect and failure mode of electrical connector,the contact failure is the main failure mode.The influence of insertion-extraction on the contact performance of electrical connector during storage is studied from the micro level.The results show that insertion-extraction will wear the gold plating layer and oxide film on the contact surface,and the growth rate of the oxide film on the contact surface is accelerated.At the same time,the contact resistance of electrical connector after insertion-extraction will increase suddenly.In chapter 3,the accelerated degradation tests considering insertion-extraction and no insertion-extraction are designed.The effect of insertion-extraction on the contact performance ofelectrical connector is verified by the accelerated degradation path of the contact resistance,and it is concluded that insertion-extraction will not only accelerates the degradation rate of electrical connector,but also cause the phenomenon of resistance jump to the degradation trail of electrical connector.And the amplitude of jump and the rebound time of jump are analysed.Furthermore,SEM and EDS are used to confirm the failure mechanism of electrical connector considering insertion-extraction.In chapter 4,based on the theory of electrical contact,the reliability evaluation model of electrical connector considering insertion-extraction is proposed.Then the parameters in this model are estimated by the least square method and the storage reliability of electrical connector considering insertion-extraction is obtained by using this model.Based on the data obtained from the accelerated degradation test,the storage life of the electrical connector is predicted,and it is about 32 years in normal environment.Chapter 5 gives a summary of the research contents and some suggestions for future research direction.