Reliability Test Evaluation Of Electrical Connectors Under High Temperature And Vibration Stress

Electrical connectors is an important carrier used to transmit electrical energy and signals between equipment,it has a wide range of applications and a large number of applications in aerospace and weapon systems.With the development of the international strategic situation and the progress of science and technology,a variety of advanced weapons and equipment appear in the military system.The electrical connector equipped near the engine is often subjected to high temperature,vibration and other extreme stresses,and the reliability of the high temperature electrical connector in this extreme environment puts forward higher requirements.At present,research on the reliability of electrical connectors mainly focuses on the evaluation of reliability in storage environments,but the research on reliability under high-temperature and vibration stress during operation is very shallow.It mainly focuses on material selection,contact failure analysis,and overall structural design.The performance degradation laws of key components are unclear.Reliability design,analysis and evaluation of electrical connectors suitable for high temperature and vibration extreme stress can only be conducted based on experience or foreign standards.In order to determine whether the electrical connectors can maintain high reliability when working under extreme stress,it is necessary to study the reliability evaluation methods of electrical connectors in hightemperature and vibration environments.This paper takes the J58 high-temperature electrical connector as the research object,systematically analyzes its main failure modes and corresponding failure mechanisms under high-temperature and vibration environment,established reliability models for contact and insulation components based on failure mechanisms,designs a high-temperature and vibration combined stress test plan,and conducts reliability evaluation of electrical connectors under high-temperature and vibration environment.This paper is divided into six chapters,and the main content of each chapter is as follows:In Chapter 1,the background and significance of this paper are firstly elaborated,and the research status of reliability engineering,reliability test,performance degradation modeling method,performance degradation data statistical analysis and electrical connector reliability are summarized respectively.The deficiencies of existing research are put forward,and the research objectives and content of this research are clarified.In Chapter 2,firstly,the main structure,materials and function of J58 high temperature electrical connector are analyzed.Secondly,it analyses the main stresseshigh temperature and vibration that it is subjected to while working.Subsequently,the main failure modes of electrical connectors under high temperature and vibration environments are identified-contact failure and insulation failure,and the failure mechanisms corresponding to the two failure modes are comprehensively analyzed,which lays a foundation for the subsequent establishment of reliability models and the formulation of test scheme.In Chapter 3,the mathematical expressions characterizing contact performancecontact resistance and insulation performance-insulation resistance are presented respectively.Based on the analysis of their failure mechanisms under high temperature and vibration environments,the growth laws of oxidation and corrosion products in the contact and the change laws of electrical conductivity of the insulation are presented.Subsequently,the performance degradation model and reliability model of contact resistance and insulation resistance are derived.Finally,based on the structural characteristics of the electrical connector,a reliability model of the electrical connector under high temperature and vibration environments is given.In Chapter 4,based on the failure mechanism analysis of electrical connectors,taking into account both the shortest time for performance degradation and the maximum number of stress cycles to obtain more degradation data,the stress application sequence,application time,and application frequency of electrical connector contact parts and insulation parts are determined respectively.The temperature rise of internal components of electrical connectors under high temperature environment is simulated and analyzed,and the temperature variation rule with time is obtained.Based on this,a high temperature and vibration stress combination test scheme for electrical connectors is established.In Chapter 5,using the maximum likelihood estimation method,statistical analysis is conducted on the performance degradation data of the contact and insulation parts,and the unknown parameters in the performance degradation model and reliability model of the contact and insulation components are estimated separately,achieving the reliability evaluation of electrical connectors,identify weak components of electrical connectors under high temperature and vibration environments.Subsequently,the rationality of the contact failure mechanism analysis is verified using scanning electron microscopy and energy spectrum analyzer,and the rationality of the insulation failure mechanism analysis is verified using infrared spectroscopy analyzer.Chapter 6 summarizes the content of the full text and prospects the next research work.