{"title":"High-Resolution Millimeter-Wave Near-Field Evaluation of Additive Manufactured (AM) Polymeric Structures","authors":"F. Ahmadi, M.T. Al Qaseer, R. Zoughi","doi":"10.32548/rs.2022.012","DOIUrl":"https://doi.org/10.32548/rs.2022.012","url":null,"abstract":"Additive manufacturing (AM) is a rapidly growing industry whose utility has been expanded beyond metals and to other materials such as polymers, ceramics, and concrete, to name a few. However, advancement in the development of inspection techniques, particularly in-line nondestructive testing (NDT) methods, lags significantly. Most of the research in developing such methods has focused on metal-based AM. This paper presents a high-resolution dielectric-loaded waveguide probe for detecting small flaws in 3D printed polymeric structures. The electromagnetic (EM) design and optimization of such a probe are discussed in this paper. The probe design is based on concentrating the interrogating electric field of an open-ended waveguide in a thin dielectric slab insert. This results in obtaining a higher spatial resolution than when using only the open-ended waveguide. Subsequently, such a probe was fabricated at a frequency of 74 GHz (V-band (50-75 GHz)) and was used to raster scan a Thermoplastic Polyurethane (TPU) sample, with very small surface flaws, to generate a near-field image. The resulting image confirms the usefulness of this technique as a potentially viable method for in-line monitoring of polymeric AM structures.","PeriodicalId":367504,"journal":{"name":"ASNT 30th Research Symposium Conference Proceedings","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123697576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}