Defects detection in al sic metal matrix composite materials using active pulsed infrared thermography apirt by data and image processing compared with the traditional ndt methods

Abstract

The aim of this research is to detect the defects on tensile specimen of Al/ SiC metal matrix composite by using Active Pulsed Infrared Thermography Technique (APIRT). APIRT is a powerful non-destructive evaluation tool for on-line monitoring of real defects of MMC which gives an accurate region of defects with respect to temperature variations. APIRT technique includes many aspects like speed, accuracy, volumetric coverage, high resolution, reliability and also detail informative image about defect. Al/SiC composites have high strength, high resistance to wear and low weight properties which make them demandable in many industrial applications such as marine, electronic packages, cost-effective solutions for many thermal management problems, automotive and aerospace industries. 30 numbers of Al/SiC metal matrix composite specimens (A, B and C sets) were prepared by stir casting technique, out of which 20 specimens were defect free with different compositions and the remaining with induced defect and cut as per the ASTM standard B577M-14.The SEM experiments have been carried outfor proving the occurrence of defects. Also, hardness test was conducted for mechanical characterization and only one Al/SiC MMC specimen was taken for finding the tensile strength of the same. Modern NDT, thermography (APIRT) had been conducted for analyzing the defects on the A,B and C sets. These 30 numbers of Al/ SiC MMC specimens were periodically heated by pulse surface heating using halogen lamp for a specific time. The Al/SiC MMC coupon s surface temperature was measured during the cooling process by IR camera. The defects were detected by means of thermographic image analysis using SMART VIEW 3.1 tool. The APIRT experimental result showed that the Al/ SiC MMC tensile coupon s sub surface region with defect revealed higher temperature than region without defect and also cooling down process proceeded longer in the region with defect. These same coupons also had been tested and compared with three traditional non-destructive techni