Eddy Current Assessment of Near-Surface Residual Stress in Shot-Peened Inhomogeneous Nickel-Base Superalloys
Source abstract
Abstract
Recently, it has been shown that shot-peened nickel-base superalloys exhibit an approximately 1% increase in apparent eddy current conductivity at high inspection frequencies, which can be exploited for nondestructive subsurface residual stress assessment. Unfortunately, microstructural inhomogeneity in certain as-forged and precipitation hardened nickel-base superalloys, like Waspaloy, can lead to significantly larger electrical conductivity variations of as much as 4‐6%. This intrinsic conductivity variation adversely affects the accuracy of residual stress evaluation in shot-peened and subsequently thermalrelaxed specimens, but does not completely prevent it. Experimental results are presented to demonstrate that the conductivity variation resulting from volumetric inhomogeneities in as-forged engine alloys do not display significant frequency dependence. This characteristic independence of frequency can be exploited to distinguish these inhomogeneities from nearsurface residual stress and cold work effects caused by surface treatment, which, in contrast, are strongly frequency-dependent.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Non-Destructive Testing Techniques · Welding Techniques and Residual Stresses · Hydrogen embrittlement and corrosion behaviors in metals
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References (13)
Show source-provided references
1. N. Goldfine, Real-time, quantitative materials characterization using quasistatic spatial mode sensing, 41st Army Sagamore Conference (August, 1994).
2. N. Goldfine, D. Clark, and T. Lovett, Materials characterization using model based meandering winding eddy current testing (MW-ET), EPRI Topical Workshop: Electromagnetic NDE Applications in the Electric Power Industry (Charlotte, NC, August 21–23, 1995).
3. F. C. Schoenig Jr., J. A. Soules, H. Chang, and J. J. DiCillo, Eddy current measurement of residual stresses induced by shot peening in titanium Ti-6Al-4V, Mat. Eval. 53, 22(1995).
4. N. Goldfine and D. Clark, Near surface material property profiling for determination of SCC susceptibility, EPRI Balance-of Plant Heat Exchanger NDE Symposium (Jackson, WY, June 10–12, 1996).
5. H. Chang, H. F. C. Schoenig Jr., and J. A. Soules, Eddy current offers a powerful tool for investigation of residual stress and other metallurgical properties, Mat. Eval. 57, 1257 (1999).
6. A Primer on the Alternating Current Potential Difference Technique (Matelect Systems, Nepean, Ontario, 1999) pp. 18–21).
7. A. I. Lavrentyev, P. A. Stucky, and W. A. Veronesi, in Review of Progress in QNDE Vol. 19 (AIP, Melville, 2000) pp. 1621–1628).
8. J. M. Fisher, N. Goldfine, and V. Zilberstein, Cold work quality assessment and fatigue characterization using conformable MWM eddy current sensors,49th Defense Working Group on NDT (October 31–November 2, 2000).
9. V. Zilberstein, Y. Sheiretov, A. Washabaugh, Y. Chen, and N. J. Goldfine, in Review of Progress in QNDE Vol. 20 (AIP, Melville, 2001) pp. 985–995).
10. M. P. Blodgett and P. B. Nagy, Eddy current assessment of near-surface residual stress in shot-peened nickel-base superalloys, J. Nondestr. Eval. 23, 107 (2004)).10.1023/B:JONE.0000048866.40648.fe ↗
11. F. Yu and P. B. Nagy, Simple analytical approximations for eddy current profiling of the near-surface residual stress in shot-peened metals, J. Appl. Phys. 96, 1257 (2004).10.1063/1.1762708 ↗
12. F. Yu and P. B. Nagy, Piezoresistive effect for near-surface eddy current residual stress assessment, in Review of Progress in QNDE Vol. 24 (AIP, New York, 2005) pp. 1371–1358).
13. M. P. Blodgett, F. Yu, and P. B. Nagy, Eddy current nondestructive residual stress assessment in shot-peened nickel-base superalloys, in Review of Progress in QNDE Vol. 24 (AIP, New York, 2005) pp. 1347–1354).