摘要:

A brief review is given on the use of ultrasonic techniques for the detection of cracks in metallic tubes. A new approach utilizing the interference between waves scattered from a crack and the one directly transmitted is described, and some results obtained for the detection of slots machined on the tube surface are presented.

ISSN:0278-0895    

DOI:10.1080/10589758608952922

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A multi-frequency eddy current testing technique is presented that is useful for detecting and distinguishing cracks, conductivity and thickness variations. By means of a conventional, bridge-type instrument and a network analyzer that measures resistance and reactance accurately, some structural inhomogeneities and cracks in metal matrix composite tubes are identified.

ISSN:0278-0895    

DOI:10.1080/10589758608952923

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A real-time ultrasonic technique for the nondestructive evaluation of ceramic powders during compaction has been demonstrated. Initial results indicate that this technique can detect the presence of hard agglomerates in a spray-dried alumina powder. The proposed sensor could be employed by industry to spot flawed parts prior to removing them from the die, and to provide on-line criteria for control of compaction parameters.

ISSN:0278-0895    

DOI:10.1080/10589758608952924

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Acoustic emission activity had been noted previously on corroding steel structures. This work identified the acoustic outputs from the various potential oxides formed and from paint fracture. By an algebraic prcoess it proved possible to determine when corrosion commenced and what oxide species were involved. High correlation co-efficients were determined throughout the whole work and it was finally shown that corrosion films as thin as 10 μm or as light as 3.5mg could be detected.

ISSN:0278-0895    

DOI:10.1080/10589758608952925

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A precision double-probe ultrasonic goniometer and two air-backed ultrasonic transducers were designed and constructed for use in the investigation of the surface and sub-surface structures of engineering materials, using the ultrasonic water immersion technique. The instrument has specifications which are a considerable improvement over those described elsewhere. Measurements with high frequency Lamb waves in thin films are described.

ISSN:0278-0895    

DOI:10.1080/10589758608952926

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The influence of magnetic permeability in eddy-current testing is considered together with its measurement and with means of eliminating it when detecting defects in ferromagnetic metals. Uncertainties in defining magnetic permeability are shown to present a drawback to standardising the testing of metals subject to magnetic hysteresis.

ISSN:0278-0895    

DOI:10.1080/10589758608952927

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor