Research On Accelarated Life Test Of Electrical Connecters Storage Reliability

In this dissertation, combined with National Civil Aerospace Science and Technology pre-research project and Second Artillery Weapons and Equipment pre-research project, a reliability model was developed and investigated to assess the storage reliability of the Y11X-1419 electrical connector. With identifing the failure mechanism, an approach about step-stress accelerated life test (ALT) and a corresponding statistical methodology were developed. During fulfill this work, the main research includes:Firstly, the historic evolution of reliability engineering from yesterday to today and the methods and trends for reliability test and statistic were briefly re-visited and highlighting some of the major achievements and transformations occurred through the years. This paved the way for the reasearch about the storage reliability of the Y11X-1419 electrical connector.Secondly, by identifing the failure mechanism of electrical connectors under storage condition, physics of failur model was developed and the distribution used in characterizating lifeof electrical connector was investigated, which paved the way for carrying out the storage reliability test planning and developing a statistic method for reliability.Thirdly, based on principle and methodology for the step-stress ALT, a method used in optimum design of the step-stress ALT planning for electrical connectors under storage conditions in maximum likelihood estimation(MLE) method. The optimized results indicated that there are three advantages for step-stress ALT comparing with constant-stresses ALT under the same confidence interval:1) shorten test time; 2) reduce size of test samples; 3) realize fast assessment for storage reliability of the electrical connector.Fourthly, a method was developed to evaluae ALT planning in Mento Carlo with criterion of reducing mean variances and standard distance values of estimated median lives. An optimal step-stress ALT planning was investigated and the steps about how to carried out the planning(e.g., test time, test temperature) was given.Fifthly, the parameter and eigenvalue of the life function(model) was evaluated using MLE according to test date collected from the step-stress ALT for electrical connector.Sixthly, the reliability model for step-stress ALT planning was investigated by probability ploting technique and Van-Montfort numerical technique.Finally, a conclusion was made and the future research about the reliability test of electrical connector was briefly presentated.