碳纤维复合材料红外无损检测的数值模拟.pdfVIP

Abstract Using the large-scale finite element analytic software ANSYS ，the transient temperature field of carbon fiber composite, stainless steel 9Cr18 and cast aluminium ZL201 and titanium alloy TC3 were simulated. The defect depth, size and thickness, intensity of heat current, monopulse, multi-second heating on the thermography difference and thermography contract of the carbon fiber composite were calculated and analyzed. The effect of different and defects materials on thermography difference and contrast were analysised. The main results were obtained by computational analysis as follows: (1) When there are some surface defects, bigger defects, thicker defects in the sample, the values of temperature difference and the extreme thermography contrast are larger, the results show that the surface defects, bigger defects and thicker defects are easy to be detected, and have the higher sensitivity. (2) The intensity of heating has changed thermography difference, but which has no effect on the best detection time and thermography contract. The results show that the theoretical detection sensitivity and the best detection time have relative with the heating intensity. (3) The different size and the depth of the air defects in carbon fiber composite materials have been quantitatively analyzed. The results show that the major shortcomings of the surface need the minimum heat flux; in the deeper detection of small defects need the greatest heat flux in the testing. When the heating time is for the 0.05s and the extreme value of surface temperature contract is 0.2 ℃. (4) The total heat input constantly, the monopulse is studied by changing the heating time and heat flux. The results show that,