NSTD Research Projects: TRP
Proposals
Quarterly Reports
2002:
3rd,
4th
2003:
1st,
2nd,
3rd,
4th
2004:
1st,
2nd,
3rd,
4th
2005:
1st,
2nd,
3rd,
4th
2006:
1st,
2nd,
3rd,
4th
Annual Reports
2002-2003
(submission)
2003-2004
2004-2005
2005-2006
2006-2007
Other
TRP -> Campaign/Number -> TRP 14
TRP 14. Use of Positron Annihilation Spectroscopy for Stress-Strain Measurements
May 2002 - December 2006
Research Objectives & Methods
The primary objective of this task was to evaluate the feasibility of the characterization of residual stresses in plastically-deformed and welded structural materials using a new nondestructive technique based on PAS. The residual stresses measured by a modified PAS method have been compared to those measured by three other techniques, namely the Ring-Core (destructive), X-Ray Diffraction (non-destructive), and Neutron Diffraction (non-destructive).
All four techniques have been used to evaluate residual stresses in cold-worked, plastically deformed and welded specimens of austenitic Type 304L Stainless Steel (SS), and martensitic Alloys EP-823 and HT-9. Alloy EP-823 is a leading target structural material to contain the molten lead-bismuth eutectic nuclear coolant needed for fast spectrum operations of an Accelerator-Driven Transmutation System. Type 304L SS is a universally-known corrosion resistant low-carbon iron-nickel-chrome alloy having optimum formability and weldability. Alloy HT-9 is known for its superior high temperature tensile properties. The metallurgical microstructures and the nature of defects have been analyzed by optical microscopy, scanning electron microscopy, and TEM.
Researchers
- Ajit Roy, Mechanical Engineering
Collaborators
- Stuart Maloy, AFCI Materials Team Leader, Los Alamos National Laboratory
- J. Frank Harmon, Director, Idaho Accelerator Center, Idaho State University
- Doug Wells, Associate Professor, Department of Physics, Idaho State University
- Farida Selim, Post Doctoral Researcher, Idaho Accelerator Center, Idaho State University
Students
-
Subhra Bandyopadhyay, Masters, Mechanical Engineering
(MS Thesis Not Available) -
Silpa Suresh Budugur, Masters, Mechanical Engineering
(MS Thesis Not Available) -
Srinivas Chanda, Masters, Mechanical Engineering
(MS Thesis Not Available) -
Satish Babu Dronovalli, Masters, Mechanical Engineering
MS Thesis - Raghunandan Karamcheti, Masters, Mechanical Engineering
- Vikram Marthandam, Masters, Mechanical Engineering MS Thesis
-
Anand Venkatesh, Masters, Mechanical Engineering
MS Thesis - Bhagath Yarlagadda, Masters, Mechanical Engineering