Research On The Application Of Ultrasonic Testing Technology In Fretting Wear Detection Of Electrical Connectors

Electrical connector is the basic electromechanical component that realizes the electrical connection and signal transmission between the devices.It is widely used in military equipment and aerospace equipment.The reliability level of the electrical connector has an important impact on the safe and reliable operation of the system.Vibration stress is one of the most important factors affecting the reliability of electrical connectors.Continuous mechanical vibration stress can cause fretting wear on the pins and jacks of electrical connectors,which affects contact performance.Therefore,this paper uses ultrasonic testing technology to study fretting wear.Firstly,this paper briefly introduces the research methods of fretting wear of electrical connectors at home and abroad,the development history and current status of ultrasonic testing technology,which lays the foundation for the research of fretting wear of electrical connectors.Then the basic structural characteristics and performance of the electrical connector are analyzed,and the detection method of the wear distribution between the contacts of the electrical connector is determined by comparing different non-destructive testing methods and structural features of the contact and test requirements.Secondly,an electrical connector fretting wear ultrasonic detection system is set up,which includes micro-motion driving mechanism and ultrasonic detecting mechanism.It can apply the micro-motion excitation to the electrical connector contact and test wear debris generated between the contacts in fretting wear.A two-pin type electrical connector of a certain type is selected as the research object.The distribution and evolution of wear debris between the contacts of the electrical connector under fretting wear conditions are obtained.From the theoretical point of view,the mechanism of the influence of various factors on the fretting wear of the electrical connector is analyzed.Thirdly,according to the experimental data,the effects of vibration frequency,vibration acceleration and vibration times on the fretting wear degree of the electrical connector are studied.The degree of wear debris at different positions in the contact area of the contact is analyzed.From the theoretical point of view,the mechanism of the influence of various factors on the fretting wear of the electrical connector is analyzed.At last,the correctness of the ultrasonic testing results is verified from the microscopic point of view.The surface morphology and energy spectrum of the pin surface before and after the test are analyzed by scanning electron microscopy.The surface morphology and material at different positions of the pin contact area before and after the test are studied.The influence mechanism of vibration frequency,acceleration and vibration times on the fretting wear of the electrical connector is obtained.