Date: Thursday, May 22nd
Presenter: Richard Wright, Idaho National Laboratory
Materials for structural applications in nuclear power plants require much more rigorous assessment compared to those operating under similar conditions in fossil power plants; thus there are currently only five materials available to the nuclear system designer compared to a pallet of about 150 for non-nuclear pressure vessels. Interest in very high temperature gas cooled nuclear reactors has reinvigorated efforts to qualify a nickel alloy for use up to 950 C in the intermediate heat exchanger. At this temperature properties that are not typically thought to be significant, such as strain rate sensitivity and stress relaxation, become critical to understanding material behavior. This talk will highlight some of the challenges associated with sorting out the complex inter- relationships of creep, fatigue and tensile properties in the commercial nickel based material Alloy 617 so that it can be qualified for nuclear design in the 750 to 950 C temperature range. Several approaches that are applied to engineering data to allow extrapolation of properties measured on laboratory time scales to 15 to 20 year heat exchanger lifetimes will be presented.
Dr. Wright has been a scientist at INL since March of 1985. He earned his B.S. (1976), M.S. (1978) and Ph.D. (1982) degrees in Metallurgical Engineering at Michigan Technological University. Dr. Wright is presently principal investigator and technical lead for the Next Generation Nuclear Plant (NGNP) High Temperature Metals Research and Development Program.
Dr. Wright has an understanding of the issues associated with the use of high temperature metals in both 3rd and 4th generation nuclear power plants and has become the technical lead for NGNP High Temperature Metal research and development. In this capacity he is leading a team of about 10 researchers in characterizing potential metals to be used at much higher temperatures than previously used for applications in very high temperature gas reactors.