摘要:

A noncontact optothermal method is described for possible application to routine industrial evaluation of the degree of cure in polymeric composites. The surface of the part is heated by a laser beam or other radiative source while its temperature evolution is continuously monitored with an Infrared detector. A strong exothermal peak is observed when the material is partially or totally uncured. Changes in the signal shape related to variations of the part geometry or environmental conditions are minimized by a differential approach comparing subsequent heat cycles on the same area. Results obtained with cured or uncured graphite-epoxy prepreg sheets are presented.

ISSN:0278-0895    

DOI:10.1080/02780898708952928

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Elastic wave propagation in a bounded medium significantly differs from that in an unbounded medium. The bounded medium in the form of a cylinder acts like a solid waveguide directing the wave with its geometry. A continuous or a pulsed wave interacts with cylindrical boundaries producing mode-converted signals in addition to the backwall echo. The signals are received at constant time Intervals directly proportional to the diameter of a solid cylindrical object such as a bolt or an anchor stud. The Cylindrically Guided Wave Technique (CGWT) makes intelligent use of the mode-converted signals, or trailing pulses, to detect corrosion wastages in cylindrical objects.

ISSN:0278-0895    

DOI:10.1080/02780898708952929

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

ISSN:0278-0895    

DOI:10.1080/02780898708952930

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor