Study On The Influence Of Closing Quantity And Plating Thickness On The Storage Life Of Contact Parts

Electrical connectors are crucial electronic parts of aeronautical systems that are in charge of electrical signal transfer and circuit connectivity.The reliability of the contact component,which is essential to the electrical connector’s capacity to transmit electrical signals,directly affects the electrical connector’s overall reliability.Due to its straightforward design and affordable processing,the slotted and closed contact is currently one of the most regularly used types of contacts in electrical connectors.The slotted connector contact is used as the study object in this paper.The performance deterioration and storage life evaluation of the contact is based on the angle of the slotted closing quantity and the thickness of the gold plating layer,two important design characteristics that determine the contact performance.The details of the study’s substance are as follows:Temperature is the primary environmental component that impacts the deterioration of contact qualities of the contacts,according to an analysis of the storage environment effect of electrical connectors.The cause of the rise in contact resistance in the storage environment was examined based on the pore properties of the gold layer on the surface of the contact components.The oxidation reaction that occurs in the pores of the contact surface to form an oxide film is what causes the contact parts to fail in storage,and the effect of variables like temperature,the thickness of the gold layer,and the degree of grooving on the rate at which the contact properties degrade was examined.Based on Hertz theory,the contact mechanics model of the contact was established,and the subsequent tests were carried out by characterizing the closing volume of the contact with the inserting and pulling force.Based on the contact failure mechanism of the contacts and the mathematical model of the contact resistance of the contacts,the Greenwood-Williamson model and the chemical reaction theory,the contact degradation trajectory model and the accelerated degradation equation of the contact performance of the slotted contacts were established,which took the closing quantity,coating thickness and ambient temperature into account,and combined with the statistical distribution theory.Finally,the storage reliability statistical model of the contact is established.The combination of each test component was determined using the orthogonal experimental design method.The contact parts were categorized according to various degrees of plating thickness and inserting and pulling force through testing the uniformity of surface plating thickness and inserting and pulling force of the test samples of the contact parts.The results of the grouping were used to develop an accelerated test scheme for electrical connector contacts,which used temperature as the accelerating stress and insertion and pulling force(the amount of closing)and coating thickness as the design variables.16 groups of accelerated degradation tests were then conducted using this scheme.The single factor effect and the interaction effect between multiple components of the test factors were both analyzed using the range analysis approach.According to the results,temperature had the biggest impact on the contact parts’ performance degradation.Raising the temperature would hasten the rate at which the contact resistance of the contact parts grew,whereas raising the insertion force and the thickness of the gold coating would have slowed it down.Moreover,there is a sizable interaction effect between the insertion and pulling force and temperature,but there is a much smaller interaction effect between these two factors and the coating thickness,temperature,and thickness of the coating.The mechanical model translated the insertion force into the sealing quantity.The maximum likelihood estimation approach was used to estimate the storage life of the contacts with varying sealing quantities and coating thickness,and the life evaluation method for the contacts with different sealing quantities and coating thickness was provided.The established contact degradation trajectory model,contact degradation rate distribution,and accelerated degradation equation were all validated using the goodness of fit test,A-D test,and variance analysis.Finally,scanning electron microscopy and energy spectrum analysis were used to confirm the failure mechanism.