ASNT

to change the society name again; it became the American Society for Nondestructive Testing (ASNT). ASNT can be proud of its role in advancing the state-of-the-art of nondestructive testing and X-ray technology. The national conferences, the section meetings for local information exchange, the topical conferences, the society’s interna- tional participation, the Nondestructive Testing Handbook series, and educational and personnel activities all provided opportunities for exchange of nondestructive testing information. The early issues of the journal were heavily weighted toward X-ray technology, ref lecting the original name of the society. Early contributors to the journal included many respected engineers and scientists, such as Arthur Barkow, Charles Barrett, and George Clark (all of whom made early contributions to the advancement of X-ray diffraction), James Bly and Gerold Tenney (whose work included developments in high-energy radiography), Donald O’Connor (whose group at the Naval Ordnance Laboratory, with colleagues Edward Criscuolo, and Daniel Polansky, contributed much to the early X-ray nondestructive testing standards), Leslie Ball (an early user of X-ray technology in the aircraft field), Donald Kerst, the developer of the betatron, film research workers Herman Seeman and George Corney, and many others whose names and works were well-known. Along the way there have been many notewor- thy radiographic applications. Materials Evaluation readers may recall the following: the Vatican Pieta (June 1964), the world’s largest radiograph (November 1964), the Liberty Bell (February 1976), a lighthouse (March 1980), the US Capitol (September 1985) and the Statue of Liberty (October 1985). The journal has also provided an opportunity for commercial development of X-ray technology. Early advertisers in the journal included equipment suppliers such as General Electric, Keleket, North American Philips, Picker, and Westinghouse; film suppliers such as Agfa Ansco, DuPont and Eastman Kodak; and tube/accessory suppliers such as Bar-Ray Products, Machlett, Pako and Ray Proof Corporation. Only a few of these early X-ray companies continue to supply the X-ray nondestructive testing market

in the 21st century; others, such as Keleket and Machlett, have disappeared completely. Many of the society honors and awards have had a radiation connection. The Coolidge Award, named for William D. Coolidge, the inventor of the hard vacuum X-ray tube (Figure 17a), was presented from 1953 to 1964 for outstanding contributions “to the advancement of nondestructive testing using X-rays.” The Lester Honor Lecture, named for the X-ray pioneer Horace Lester (Figure 18), has been presented since 1943. The Mehl Honor Lecture, named for Robert Mehl, an early contrib- utor to gamma radiography (Lambert 1976), has been presented since 1941. Although the honor lectures are named for men known for their work in radiation, the topics of the lectures cover the entire field of nondestructive testing. The two lectures were combined into one — the Lester/Mehl Honor Lecture—in 2018. The period from 1935 to 1960 saw improvements in technology and techniques for radiation safety (Morgan 1971), gamma radiography (Briggs 1981; Moore 1985; Bell 1984), portable X-ray machines (Bell 1984; Hovland 1985), high-voltage radiography (O’Connor and Cunningham 1949; Straw 1984b; Straw 1984c),and nucleonic gauging (Davis 1989). Radiographic testing found new applications, in metals (Henry 1989), shipbuilding (Lutts 1954), and particularly in the aviation industries (Itoh 1982; Straw 1984a; Hagemaier 1985). Although radiographic testing is still performed essentially in the same through- transmission, direct shadowing way that Röntgen used 100 years ago, the twenty-first century has much better X-ray sources, detectors, and understanding of image quality factors like scatter and unsharpness. In addition, the industry today has a large arsenal of techniques — for example, digital (electronic) radiography, computed radiography, computed tomography, laminography, backscatter imaging, dual energy, microradiography, f lash techniques, and inmotion radiography. The commercial X-ray market for ADVANCES IN RADIOGRAPHIC TECHNOLOGY

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