摘要:

An ultrasonic evaluation system of soldered connections which uses a leaky Lamb wave device operating at a liquid-solid interface is described. The leaky Lamb wave device has two arched interdigital transducers on a thin piezoelectric ceramic plate. The direction of the sound beam into water is varied considerably by changing the operation frequency because of the very dispersive property of the Lamb wave. This characteristic can be used effectively for C-mode imaging. Typical examples obtained by using a reflected wave from the back surface of the IC plate are successfully demonslrated.

ISSN:1058-9759    

DOI:10.1080/02780899208953150

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The primary goal of image processing in transient thermography is to obtain a quantitative estimate of the subsurface structure from the recorded surface temperature data. The solution to this inversion problem can be separated into two stages. Potential “defects” are identified by utilising appropriate image enhancement techniques, and realistic thermal modelling is employed to analyse the Iransient temperature evolution. In this correspondence both strategies are reviewed and examples are provided where possible of their use.

ISSN:1058-9759    

DOI:10.1080/02780899208953151

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper describes a novel approach to the design of an automated system for conventional radiographic inspection of cast engineering components. The system incorporates a series of conventional image processing techniques to efficiently detect and analyse defects in the radiographic image. These are combined with an intelligent knowledge based (1KB) system, which uses a series of rules defined by expert inspectors, to interpret and evaluate defects against the quality assurance of the inspection process. A description of the overall design of the system is given, including the various image processing techniques used. The elements of the 1KB system are described, including the knowledge representation scheme, inference mechanism and control structure, and rules for classification and evaluation. Preliminary results are given indicating that the system is capable of meeting the requirements of an automated system for industrial radiographic inspection.

ISSN:1058-9759    

DOI:10.1080/02780899208953152

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The available electromagnetic methods used for the detection and measurement of metal fatigue cracks are first described. A distinction is drawn between the eddy-current and potential drop methods, which detect the crack primarily because of the break in electric conductivity, and the magnetic particle and flux leakage methods which detect the break in magnetic permeability. The importance of the skin-effect is stressed and the various frequency regimes distinguished. Theoretical models of each method are described and compared and their strengths and weaknesses discussed.

ISSN:1058-9759    

DOI:10.1080/02780899208953153

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor