Engine Titanium Consortium - Center for Nondestructive Evaluation ...

Attenuation (dB/in) .
Waspalloy Attenuation at 7.5 MHz
4.00
3.50
Axial
3.00
Hoop
2.50
Radial
2.00
1.50
1.00
0.50
0.00
0" 1" 2" 3" 4"
(center)
Measurement Site
Attenuation (dB/in) .
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
GFM-A Attenuation at 7.5 MHz
Axial
Hoop
Radial
0" 1" 2" 3" 4"
(center)
Measurement Site
Attenuation (dB/in) .
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
V-Die-A Attenuation at 7.5 MHz
Axial
Hoop
Radial
0" 1" 2" 3" 4"
(center)
Measurement Site
Attenuation (dB/in) .
V-Die-B Attenuation at 7.5 MHz
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
Axial
Hoop
Radial
0" 1" 2" 3" 4"
(center)
Measurement Site
Figure 7. Measured attenuation values at 7.5 MHz for the Ni billet specimens. Results are shown
for three orthogonal inspection directions. The distance from each measurement site to the billet
center is indicated.
Attenuation at 7.5 MHz (dB/in)
7
6
5
4
3
2
1
Correlation Between Measured Attenuation and
Measured Average Grain Diameter
GFM-A
VDIE-A
VDIE-B
Wasp
JT model for pure Ni
Waspaloy Trendline
Note : tw in boundares
w ere not counted as bona
fide grain boundaries.
Attenuation at 7.5 MHz (dB/in)
0.6
0.5
0.4
0.3
0.2
0.1
Correlation Between Measured Attenuation and
Measured Average Grain Diameter
GFM-A
VDIE-A
VDIE-B
Wasp
JT model for pure Ni
IN718 Trendline
Note : tw in boundares
w ere not counted as bona
fide grain boundaries.
Vdie_A
coupons
H, I, L
0
0 20 40 60 80 100 120
Estimated Grain Diameter (microns)
0.0
0 10 20 30 40
Estimated Grain Diameter (microns)
Figure 8. Correlation between measured attenuation at 7.5 MHz and estimated average grain
diameter. Right panel shows a blow-up of the region near the plot origin. The prediction of the Joe
Turner Attenuation Model (for pure Nickel) is shown for comparison, along with a trend lines
through the data with the same shape as the model curve.
Quarterly Report – January 1, 2002 –March 31, 2002
print date/time: 6/6/2002 - 8:39 AM – Page 10