Metallurgical characterization and residual stress measurements of target structural materials

This investigation is focused on the evaluation of residual stresses in target structural materials due to plastic deformation and welding by using both destructive ring-core (RC) method and nondestructive techniques including positron annihilation spectroscopy (PAS), neutron diffraction (ND) and x-ray diffraction (XRD) methods. Materials tested were austenitic Type 304L SS and martensitic Alloys EP-823 and HT-9. Types of specimen tested include cold-worked (CW), three-point-bent and welded specimens consisting of similar and dissimilar materials. The CW specimens showed increased residual stresses with an increase in cold reduction level. Measurements made on the welded specimens revealed higher residual stresses close to the fusion line (FL), which became reduced at distances away from the FL. Comparisons of RC data to those obtained on CW and welded specimens by the ND, PAS and XRD methods showed consistent stress patterns. Metallographic evaluations by optical microscopy revealed microstructures characteristic of austenitic and martensitic stainless steel showing the weld metal, heat-affected-zone and the base metal.

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor dc:publisher

University of Nevada, Las Vegas

Year

2004

Author dc:creator

• Marthandam, Vikram

Contributors dc:contributor

• Ajit K. Roy

Statement dc:rights

• IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

Language dc:language

English

Identifier

https://oasis.library.unlv.edu/rtds/1650

OAI identifier oai:identifier

oai:oasis.library.unlv.edu:rtds-2649