Research On The Effects Of Gold-plated Thickness On The Storage Life Of Cylindrical Slot Contacts

The electrical connector is a basic component of missiles and other equipment systems,and is used to realize important functions such as electrical signal transmission and energy transmission.The realization of these functions requires that the components in the electrical connector have a sufficient level of reliability,especially the electrical connector contacts,if failure occurs,it will cause signal loss and transmission interruption,which will further cause the failure of the entire system.Therefore,the reliability of the electrical connector contact is related to the reliability of the entire system.Since the electrical connector has the characteristic of "long-term storage with the missile",the performance degradation of the electrical connector under long-term storage will affect the reliability of the equipment system,so it is necessary to evaluate the storage reliability of electrical connector.The current reliability assessment of electrical connectors is mainly carried out by selecting several typical electrical connectors to carry out the test,which has the disadvantages of long test time,high cost,and narrow coverage.The reliability of the electrical connector obtained through the reliability evaluation of each component can effectively solve the above-mentioned problems.In this paper,the widely used YXXX type cylindrical slot contacts are chosen as the research object,and the effects of the gold-plated thickness on the storage life of the contacts are analyzed,which can provide basic data for the reliability evaluation of electrical connectors.The specific research content is as follows:The first chapter describes the development of storage reliability research,as well as the current research on the reliability of electrical connectors and the reliability of electrical connector contacts,including a review of research plans and test specifications at various stages,an introduction of typical storage reliability test projects,and a summary of research results in mechanism analysis,reliability modeling,etc.The research objectives and research content of this article are clarified according to the current research status of electrical connector contacts.The second chapter summarizes the characteristics of electrical connector contacts,especially the structure and material of the cylindrical slot contacts,analyzes the actual storage environment of the contacts,clarifies the main environmental stresses on the contacts,and focuses on the failure reasons and mechanisms of contacts under storage environment,reveals the role of the gold-plated thickness and quantifies its impact.In the third chapter,the typical plating thickness contacts produced are studied according to the relevant research experience,and the samples needed for the accelerated test are determined based on the research results;by referring to the electrical connector test experience and the plan design theory,the accelerated test plan for the contacts with three plating thicknesses is determined.In chapter 4,the constant stresses test is completed according to the accelerated test plan,and based on the contact resistance degradation data,the relationship between the contact resistance increment and the gold-plated thickness is analyzed,and the influence of the presence or absence of the plating layer and the gold-plated thickness on the degradation of contact performance is summarized;a reliability statistical model of the contacts considering the gold-plated thickness is established,and the relationship between the model parameters and the gold-plated thickness is determined by a two-step estimation method,the median life of the contacts with different gold-plated thickness is calculated.In chapter 5,the verification of the stochastic process performance degradation model and failure mechanism of the contacts is completed: the applicability of the model is qualitatively verified by analyzing the box plot and residual box plot;probability graph test and numerical test method are used to further prove that the contact resistance increment obeys the normal distribution,which quantitatively verifies the applicability of the model;the surface morphology and element content of the contacts after the test are analyzed to prove the correctness of the failure mechanism analysis.In chapter 6,the research content of the whole dissertation is summarized,and a prospect is made based on the deficiencies in the research of this dissertation and the parts that are not involved.