The Application, Challenge, and Developing Trends of Non-destructive Testing Technique for Large-scale and Complex Engineering Components Fabricated by Metal Additive Manufacturing Technology in Aerospace

Metal additive manufacturing (MAM) technology provides a direct and efficient way for large-scale, integrated, and sophisticated engineering components in the aerospace field. Non-destructive testing (NDT) technique has been proven to be a significant method for quality evaluation of MAM components without destructing the integrity and performance of the components. However, it is still a challenging task that how to accurately and efficiently achieve the quality evaluation of large-scale and complex MAM engineering components using NDT technique. Nowadays, most studies mainly focus on the quality evaluation of small specimens or simple structure components, with comparatively less on the assessment of large-scale or complex engineering components. Thus, this review briefly introduced three urgent demands for quality evaluation of as-fabricated large or complex structure components and eight conventional NDT techniques possibly used for the quality detection of MAM. Four main challenges and future development trends in NDT technique are discussed in detail according to testing ability, data processing ability, and test standards. Among the future development trends, the application of machine learning and digital twins in NDT technique are the most promising method for intelligent detection and quality prediction of components. This work aims to provide a insight to enlarge the application of engineering components fabricated by MAM.