Detection of discontinuities in friction stir welded components.

Author

Harsha Jyoti Phukan

Abstract

"This work looks into the detection of two major types of flaws occurring in friction stir welds - advancing side wormholes and root side kissing bonds. The latter being a laminar type of defect, located towards the root of the weld, is more difficult to detect using nondestructive methods. Butt weld samples from a design of experiment matrix with imposed skin-to-skin gaps of known width at the joint were destructively examined and the discontinuities found in them were catalogued. A relationship defining the process parameter limit for wormhole-free welds is established. Further, samples from another design of experiment matrix of wormhole-free welds were nondestructively examined for root side kissing bonds using relatively low frequency eddy current. A statistically significant correlation is established between height of kissing bond and corresponding normalized reactive voltage. Finally, the detection capability of the eddy current method is quantified using two methods - Monte Carlo simulation and probability density functions of normalized reactive voltage for zero and non-zero flaw conditions. The latter approach provides a relationship between flaw size and detection capability"--Abstract, page iii.

Advisor(s)

Richards, Von

Committee Member(s)

Liou, Frank W.
Krishnamurthy, K.

Department(s)

Mechanical and Aerospace Engineering

Degree Name

M.S. in Manufacturing Engineering

Sponsor(s)

Boeing Company
U.S. Air Force Research Laboratory (Wright-Patterson Air Force Base, Ohio)

Publisher

University of Missouri--Rolla

Publication Date

Summer 2006

Pagination

xiii, 72 pages

Rights

© 2006 Harsha Jyoti Phukan, All rights reserved.

Document Type

Thesis - Citation

File Type

text

Language

English

Subject Headings

Eddy currents (Electric)
Friction welding
Nondestructive testing
Welded joints -- Testing

Thesis Number

T 9037

Print OCLC #

85775121

Link to Catalog Record

Full-text not available: Request this publication directly from Missouri S&T Library or contact your local library.

Recommended Citation

Phukan, Harsha Jyoti, "Detection of discontinuities in friction stir welded components." (2006). Masters Theses. 5930.
https://scholarsmine.mst.edu/masters_theses/5930