Research On Microwave Nondestructive Testing For Metal Surface Defects

As one of the most important means to ensure the safe operation of specialequipment, microwave nondestructive testing technology is wildly used in equipmentmanufacture, installation, daily use, maintenance and other aspects. However,nondestructive testing technology need for an innovative new technical support, due tothe chosen of the means of non-destructive testing equipment is impacted of byoperating conditions and environment, coupled with the limitations of non-destructivetesting methods themselves. As following a cooperation project, this thesis is mainlyfocus on microwave nondestructive testing technology for aircraft shell metal surfacedefects.By comparing the existing advantages and disadvantages, the non-destructivetesting techniques is completely studied in this thesis. A metal surface microwavenondestructive testing system is proposed for metal surface defecting, based on theprinciple of microwave reflection. The microwave detection system evaluates thestructural integrity of the material and products by receiving the signal amplitude,frequency and phase information from the defect sites and normal sites. This testingsystem is mainly consisting of signal transmitting, signal receiving and signalprocessing.The contributions of this thesis are as follows:1. A complete metal surface defects microwave nondestructive testing system isproposed as based on microwave reflection properties of the metal and non-metallicpenetration characteristics.2. A microwave cavity resonating probe of the microwave sensor system, which isa key component of microwave nondestructive testing system, has been designed andproduced with the aid of Ansoft HFSS software for the simulation and optimization.3. Completed the design of a microwave signal source circuit on Lmx2541chip,and MSP430F149microcontroller is utilized for the signal processing part.4. Build a system platform based on non-destructive testing of metal surfaces, andexperiment results verified the feasibility of the detection system.A prospective study of non-destructive detection technology and a new methodfor the rapid detection of aircraft metal enclosure are made, due to the reliability ofnon-destructive testing of metal surface defects and easy to used.