| Electrical connectors are widely used in aerospace,electronic communication and other fields,which play the role of signal transmission and electrical connection.The electrical connector is one of the commonly used mechanical and electrical components.Its reliable operation directly affects the safe and reliable operation of the system.High frequency vibration is one of the main factors that affect the contact performance of the electrical connector.It will cause fretting wear of contact parts of electrical connector,which will lead to the failure of them.Therefore,in this thesis,a certain type of electrical connector is taken as the research object,and the electrical capacitance tomography technology is used to study the evolution rule of fretting wear behavior and imaging technology between electrical connector contacts under high frequency vibration condition.First of all,in the analysis of research methods and electrical capacitance tomography technology of electrical connector fretting wear at home and abroad,by comparing different non-contact non-destructive testing technology,according to the contact structure characteristics and test requirements,this thesis determines the detection method of electrical connector fretting wear(wear debris between contacts);and with reference to the national test standards of electrical connector,the electrical connector is developed Fretting wear test plan.Secondly,this thesis designs a fretting wear test device for electrical connector,which consists of three parts: electric vibration drive unit,chip induction eigenvalue detection unit and contact resistance measurement unit.Thirdly,based on the built-in fretting wear test platform,this article conducts fretting wear test on electrical connectors.The distribution characteristics of the contact area wear debris accumulation area during the fretting wear of the electrical connector under high frequency vibration were studied by the number of vibrations,frequency,acceleration and direction of vibration.The amount gradually increases,the area of the wear area gradually increases,and the position of wear debris also migrates with vibration;the amount of wear debris generated at the root of the pin is the largest,and the end is the least.When the number of vibrations is the same,the increase in vibration acceleration may increase the amount of fretting displacement during each fretting.Therefore,compared with the vibration frequency,the vibration acceleration has a greater impact on the accumulation of abrasive debris and the increase in fretting wear.When the vibration direction is Z direction,the wear is more serious than X direction and Y direction.Analyze the detected contact resistance value,and then predict the remaining life of the electrical connector contacts based on the Wiener process.In addition,through SPSS software,correlation analysis shows that contact resistance and wear debris induction characteristic values show extremely high correlation under high vibration frequency and vibration acceleration.Finally,the image reconstruction algorithm of electrical capacitance tomography for fretting wear is studied,and the image results of debris distribution under Landweber and CG algorithm are analyzed.The research shows that the results of debris distribution can be seen clearly by image reconstruction.By comparing the two algorithms,we can see that CG image reconstruction algorithm has faster convergence and better imaging effect than Landweber iterative algorithm. |
