Mechanical Engineering Commons^™

High-Magnification Digital Image Correlation Techniques For Aged Nuclear Fuel Cladding Testing, Robert Scott Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nuclear fuel cladding in light water reactors, often made of zirconium alloys, is naturally made more brittle by exposure to the water coolant during normal reactor operation. However, this embrittlement by zirconium hydrides changes the mechanical behavior of the cladding material, affecting how it will deform and what may cause it to fail. Because the cladding already has different properties in different material directions, mechanical testing also needs to be direction specific. In addition, to understand the effects that these microscale hydride features have, measurements of deforming cladding need to be at a microscale. This dissertation describes several high-magnification innovations …

The Effect Of Bit Depth On High Temperature Digital Image Correlation Measurements, Steven Robert Jarrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital Image Correlation (DIC) is a camera-based method of measuring mechanical displacement and strain which is commonly used in high-temperature experiments due to its ability to take contactless measurements. High-temperature DIC is challenging due to light emitted from the sample which can saturate the camera sensor. Blue-DIC and UV-DIC have been developed to minimize this effect, but the maximum sample temperature range of DIC remains a function of the camera and camera settings. Bit depth, also referred to as color depth or number of bits, is an important camera setting which affects the dynamic range of an image, but which …

Development Of A Variable Extensometer Method For Measuring Ductility Scaling Parameters, Adam J. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ductility is the measure of how much a material can stretch before separation. It is usually measured in percent elongation, which is the amount a material stretches divided by its original length before stretching. This is an important property to understand for both the design for performance and safety. A material’s ductility can be influenced by several factors including heat treatment, machining, temperature, and radiation dose. Materials used in nuclear energy facilities are often exposed to all these factors, and it is important to be able to understand ductility at each possible combination.

Ductility is usually characterized through tension tests …