Study On Step-stress Acceleration Degradation Test Of Electrical Connector Contacts Under Vibration

The electrical connector is an indispensable component in an electrical and electronic system for transmitting electrical signals,the transmission of electrical signals is primarily accomplished by contacts.The loss of electrical signals in the system often causes system failure or even paralysis,so it is necessary to study the reliability of the contact of electrical connector.The reliability of the electrical connector contacts are mainly affected by the temperature and vibration stress.This paper mainly studied the degradation process of the electrical connector contacts under the vibration stress.In order to facilitate the observation,the Y1XX-XX circular electrical connector contacts with large contact size was selected as the research object,and the failure condition of the electrical connector contacts under vibration stress was studied from two aspects:contact characteristic simulation and accelerated degradation test.Firstly,the electrical contact failure mode of the electrical connector was discussed,and proposed the main failure causes.The finite element simulation model including contacts,rubber parts and outer ring was established,and the electrical connector contacts under different vibration excitation conditions were analyzed.The contact characteristics were used to verify the causes of electrical contact failure.Then designed step stress accelerated degradation test,and obtained the degradation data of performance characteristics.Finally,the Wiener process was used to describe the degradation process.After estimating the parameters,the life of the research object was proposed and determined the variation of life with the magnitude of the vibration.The first chapter introduced the research background and significance of this paper.It briefly described the basic theory of electrical contact and the existing failure study of the electrical connector contacts under the vibration conditions.This part summarized the accelerated degradation test methods and statistical analysis methods of degradation data.Finally,put forward the research content of this paper.In the second chapter,it was based on the understanding of the structure of electrical connector,analyzed the theoretical model of contact and contact pressure of electric connector contact,put forward the main failure mode of electric contact of electric connector contact,established the failure tree of electric contact,and expounded the failure reason of electric contact of electric connector under vibration condition.And the mechanism of contact failure caused by fretting wear and contact pressure reduction between the pin surfaces under vibration environment was analyzed.In the third chapter,based on the simplified dynamic model of contact vibration of electrical connector,the simulation model was established,and the ABAQUS was used to simulate the contact characteristics,and the change of insertion and extraction force were obtained to verify the calculation results of the theoretical model.The sinusoidal and random vibration simulation were carried out to determine the vibration response of the electrical connector contact under different vibration excitation conditions.The relative displacement between the jack and the pin and the change rule of the root stress of the jack spring were obtained,which provided the basis for the establishment of the degradation model in Chapter 4.In the fourth chapter,the degradation model of contact resistance based on Wiener process under random vibration stress was established.Considering the randomness of drift coefficient and diffusion coefficient,the acceleration model of drift coefficient and diffusion coefficient was established according to the principle of constant acceleration factor.The statistical analysis method of step stress accelerated degradation test data based on the above model was given.The step-stress accelerated degradation test scheme of contact under vibration environment was developed and the test was carried out.The failure mechanism was demonstrated by the research of the insertion and extraction force of the contact and the micro analysis of the contact surface.Verified the availability of the model by the statistical analysis of the test data.Finally,giving the relationship between the contact life and the vibration magnitude,and the rapid evaluation of the reliability of electrical connector contact under vibration environment was realized.The fifth chapter summarized the research content and results of this paper,put forward the shortcomings of the research,and the future research was prospected.