NDE Reliability and Process Control for Structural Ceramics

Preliminary Evaluation of NDE Techniques for Structural Ceramics

A preliminary evaluation of several nondestructive testing methods for flaw detection in hightemperature structural ceramic components is being carried out. The ceramics components being investigated include silicon carbide heat-exchanger tubes and silicon nitride rotors. The nondestructive evaluation techniques under consideration include dye-enhanced radiography, holographic interferometry, i...

Microwave NDE of Ceramics

The objective of this work is to evaluate the potential of microwave techniques for detecting, classifying, and determining the dimensions of inclusions and surface cracks in structural ceramics such as Si3N4. Experimental results that show the feasibility of detecting various types of inclusions and voids in Si3N4 have been obtained, and these results are reviewed. In addition, the question of...

Microwave Techniques for NDE of Ceramics

In recent years, the technology for generating and controlling electromagnetic energy at frequencies of 100 GHz and above has improved considerably, and such components are now readily available. In view of this fact, we have undertaken a program to assess the applicability of this technology to the NDE of ceramic materials and components. We have found that SijN4 is nearly transparent at these...

NDE for Bulk Defects in Ceramics

A 50 MHz C-scan imaging system is used to find defects in ceramics. The imaging system consists of a microcomputer-controlled scanner for data acquisition and signal conditioning. Synthetic aperture imaging at 50 MHz is carried out to obtain 3-D images of flaws. Image reconstruction is accomplished digitally on a minicomputer. A square synthetic aperture is used to image flaws in flat disc samp...

NDE of Ceramics and Ceramic Composites