Application of Non-Destructive Testing Techniques for the Assessment of Casting of AA5083 Alloy

Abstract

Non-destructive testing (NDT) plays an important role in quality control of cast products. Typically, all cast products are inspected for external, sub-surface and internal defects. In this study, three methods of NDT; visual inspection (V.T), liquid penetrant testing (L.T), ultrasonic testing (U.T), and a combination of DT and NDT techniques were employed to assess and evaluate the metal quality of AA5083 alloy that was produced by four different casting techniques: (i) Conventional casting, (ii) in-situ melting and solidification technique (without degassing), (iii) in-situ melting and solidification techniques with degassing (argon gas was injected vertically to the surface of the metal), and (iv) insitu melting and solidification techniques with degassing (argon gas was injected parallel to the surface of the metal). The principles of these methods are also presented, and its applications for the assessment of cast products have been highlighted. The main contribution of this paper is the application of 3D image of optical microscope technique for rough estimation of the depth of open surface defects. NDT results highlighted that the best product was produced by in-situ melting and solidification technique with degassing (argon gas injection parallel to the surface of the metal).