N eutroN I magINg of H ydrogeN IN a354 g rade Bd S teel a NcHor r odS - - PowerPoint PPT Presentation

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Sep 23, 2023 420 likes •496 views

N eutroN I magINg of H ydrogeN IN a354 g rade Bd S teel a NcHor r odS by Lisa Thomas, P .E. Metallurgist, Berkeley Research Company m eaSure H ydrogeN c oNceNtratIoN To assess the risk of environmental hydrogen embrittlement cracking to other

SLIDE 1

NeutroN ImagINg of HydrogeN IN a354 grade Bd Steel aNcHor rodS

by Lisa Thomas, P .E. Metallurgist, Berkeley Research Company

SLIDE 2

To assess the risk of environmental hydrogen embrittlement cracking to

ther A354 Grade BD anchor rods

do this... Measure H concentration in the failed rods, near the fracture and in the top ends

meaSure HydrogeN coNceNtratIoN

SLIDE 3

Neutron Tomography Gamma-Ray Activation

generate 3D maps of hydrogen concentration across the entire rod cross-section

NIST Center for Neutron Research

Dr. Daniel Hussey
Dr. Thomas H. Gnaeupel-Herold
Dr. Rick L. Paul
Dr. Richard M. Lindstrom
Dr. David L. Jacobson

NIST scientists:

SLIDE 4

all tHat IS requIred:

3-millimeter thick discs

specimens from both ends of the S1 & S2 rods & from any other rods that are available

SLIDE 5

H gradIeNt IN top eNdS vs. H gradIeNt IN Bottom eNdS

“W a s HE c r ac k i n g E xc lu s i v E to

co r ro s i o n o f b ot to m t H r E a d s?”

informs tHE managEmEnt stratEgy of

tHEr rods

SLIDE 6

These studies using neutron imaging to measure hydrogen content in A354 Grade BD steel fasteners of this size have not been done! It will be invaluable, not only for the SAS Bay Bridge but for infrastructure projects around the world!