Nondestructive Testing and Evaluation 

About: Nondestructive Testing and Evaluation is an academic journal published by Taylor & Francis. The journal publishes majorly in the area(s): Ultrasonic sensor & Nondestructive testing. It has an ISSN identifier of 1058-9759. Over the lifetime, 1000 publications have been published receiving 8679 citations.

Properties of the radiography facility neutra at sinq and its potential for use as european reference facility

Abstract: At December 3rd 1996, the spallation neutron source SINQ had its first proton beam onthe target. With a steady-state proton beam of 850 IlA this facility is now the strongest of its kind in the world. One of the first experimental facilities in operation was theradiography station NEUTRA (for NEUtron Transmission Radiography). The designwas described at earlier meetings [1,2] and the first validation measurements werereported [3]. There are some advantages in comparison to other radiography stations atresearch reactors. This will be demonstrated in detail by means of the measured valuesand examples of practical applications. The use as reference facility will be envisagedwithin an European project (COST-524).

A review of recent developments in parametric based acoustic emission techniques applied to concrete structures

Abstract: This article presents a review of recent developments in parametric based acoustic emission (AE) techniques applied to concrete structures. It recapitulates the significant milestones achieved by previous researchers including various methods and models developed in AE testing of concrete structures. The aim is to provide an overview of the specific features of parametric based AE techniques of concrete structures carried out over the years. Emphasis is given to traditional parameter-based AE techniques applied to concrete structures. A significant amount of research on AE techniques applied to concrete structures has already been published and considerable attention has been given to those publications. Some recent studies such as AE energy analysis and b-value analysis used to assess damage of concrete bridge beams have also been discussed. The formation of fracture process zone and the AE energy released during the fracture process in concrete beam specimens have been summarised. A large body of experi...

Combined laser spot imaging thermography and ultrasonic measurements for crack detection

Abstract: A surface crack, close to a small, well-defined heated spot, impedes lateral heat flow and produces alterations in the shape of the thermal spot image that can be monitored by thermography. Spot heating has been achieved using both cw and pulsed laser beam illumination on stainless steel and titanium samples and the technique has been found to be successful for determining the location of fatigue cracks. When using a pulsed laser beam one can also simultaneously generate wideband ultrasonic signals in the sample; this can be used to detect the presence of surface and sub-surface defects in the sample. Results are presented that have been obtained using a fixed camera and cw laser beam position with the sample being moved through the field of view of the camera. Results are also presented using a fixed camera and sample, with a raster scanned cw or pulsed lasers beam moving across the sample. A demonstration of how a non-contact ultrasonic measurement can be performed simultaneously is presented. Thermal i...

A new solution for automatic microstructures analysis from images based on a backpropagation artificial neural network

Abstract: This article presents a new solution to segment and quantify the microstructures from images of nodular, grey, and malleable cast irons, based on an artificial neural network. The neural network topology used is the multilayer perception, and the algorithm chosen for its training was the backpropagation. This solution was applied to 60 samples of cast iron images and results were very similar to the ones obtained by visual human tests. This was better than the information obtained from a commercial system that is very popular in this area. In fact, this solution segmented the images of microstructures materials more efficiently. Thus, we can conclude that it is a valid and adequate option for researchers, engineers, specialists, and professionals from materials science field to realise a microstructure analysis from images faster and automatically.

State-of-the-art laser adhesion test (LASAT)

Abstract: This paper proposes a state-of-the-art laser adhesion test. It consists of testing material interfaces with laser-driven shock wave. Since the first demonstration in the 1980s by Vossen, many studies and developments have been done. This paper presents recent experiments and developments on the basic physics involved. Results show the ability of the technique to perform a quantitative adhesion test for a wide range of materials and configurations. Edge effect principle and ultra-short shock wave give perspectives for new applications for multi-layer combination of material. Fundamental principles are evidenced through experiments on bulk ductile materials before demonstrating their application to coated systems.