Non-destructive thermal-wave-radar imaging of manufactured green powder metallurgy compact flaws (cracks). (March 2017)

• Record Type: Journal Article
• Authors: Melnikov, A.; Sivagurunathan, K.; Guo, X.; Tolev, J.; Mandelis, A.; Ly, K.; Lawcock, R.
• Is Part Of: NDT & E international. Volume 86(2017)
• Page Start: 140
• Page End: 152
• Publication Date: 2017-03
• Subjects: Cracks -- Non-contact -- Thermal wave radar imaging -- Automatic defect recognition -- Automotive manufacturing; Nondestructive testing -- Periodicals; Contrôle non destructif -- Périodiques; Electronic journals; 620.1127
• DOI: 10.1016/j.ndteint.2016.12.004
• Languages: English
• ISSNs: 0963-8695

Abstract

Abstract: Thermal wave radar imaging (TWRI) was developed to detect manufacturing cracks in automotive powder metallurgy components (transmission sprockets) in their green (unsintered) state. The crack detection capability of the TWRI phase was validated by two sets of cracked/crack-free green and sintered sprockets which were sectioned after TWRI measurements. An automatic defect recognition (ADR) TWR image processing method was also developed to differentiate cracks from local defects. Measurement results demonstrated that TWRI is superior to conventional lock-in thermography imaging (LITI) in both flaw detection resolution and speed, and thus is a viable green-sprocket manufacturing flaw imaging technology. Graphical abstract: Comparison between Thermal-wave-radar (TWR) original phase images (top) and Automatic Defect Recognition (ADR) processed images (bottom) of two green samples: (a) with cracks; and (b) without cracks. The regions with cracks, local defects and intact material are indicated with green, red and purple color, respectively, in the ADR processed images. Highlights: Thermal-Wave-Radar imaging of industrial metal compact defects. Automatic Defect Recognition for crack and non-crack flaw identification in metal compacts. Dynamic mid-infrared imaging of cracks at component recessed interior corners for real-time NDI. Green powder metallurgy automotive component manufacturing flaw depth-profilometric imaging.