Use of computed tomography in nondestructive testing of polymeric materials

Trial results are reported from the application of computer aided tomography (CAT) scans to nondestructive testing of industrial polymer components. The tests were carried out in a hospital and covered the detection of defects and structures in tires, a thick-walled rubber cylinder, a mirror-welded container, a filament-wound high pressure tank and a rubber spring for a reciprocating feeder. CAT scans were also performed on a fiberglass reinforced plastic reaction rod and a rubber shock absorber. The scans permitted the determination of cross-link density gradients and the bulk density of two vulcanized rubber products, i.e., a lifter bar and a thick-walled rubber cylinder. Other scans demonstrated the capability of CAT scans to reveal porosity, air entrapment and delamination as small as 0.5 mm across. (M.S.K.)