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Search Publications by: Peter Bradley (Fed)

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Displaying 1 - 25 of 55

Hydrogen Embrittlement Susceptibility and Fracture Toughness Measurements of Welded X65M Pipeline Steels

November 14, 2024
Author(s)
Newell Moser, Zack Buck, Nicholas Derimow, May Ling Martin, Damian Lauria, Enrico Lucon, Peter Bradley, Matthew Connolly
Hydrogen is known to deteriorate the mechanical performance of steels (i.e., hydrogen embrittlement). The welding processes involved in the manufacturing and joining of steel pipelines locally modifies the microstructure of the steel, further complicating

Assessing girth weld quality of pipeline steels and their susceptibility to hydrogen embrittlement

August 28, 2024
Author(s)
Zack Buck, Newell Moser, Nicholas Derimow, May Ling Martin, Damian Lauria, Enrico Lucon, Douglas Stalheim, Peter Bradley, Matthew Connolly
Hydrogen has long been considered a viable carbon-free option for ever-increasing societal desires to transform our energy infrastructure towards more renewable and alternative technologies. However, the effects of hydrogen-assisted damage mechanisms that

Effects of hydrogen on the evolution of 4130 steel microstructure as a result of tensile loading

July 12, 2024
Author(s)
Zack Buck, May Ling Martin, Damian Lauria, Jason Killgore, Peter Bradley, Yan Chen, Ke An, Matthew Connolly
Neutron diffraction and Scanning Kelvin Probe Force Microscopy (SKPFM) were used to study the evolution of lattice strain, dislocation density, and phase partitioning of a ferrite/martensite pressure vessel steel (AISI 4130) that resulted from tensile

Assessing girth weld quality of pipeline steels and their susceptibility to hydrogen embrittlement

June 16, 2024
Author(s)
Zack Buck, Newell Moser, May Ling Martin, Nicholas Derimow, Damian Lauria, Enrico Lucon, Douglas Stalheim, Peter Bradley, Matthew Connolly
Hydrogen is known to cause premature failure in various steel infrastructures due to effects of embrittlement, which is particularly detrimental to ferritic steel structures such as pipelines and pressure vessels. Therefore, understanding the

Effects of mechanical deformation on dislocation density and phase partitioning in 4130 steel

August 22, 2023
Author(s)
Zack Buck, Matthew Connolly, May Ling Martin, Damian Lauria, Jason Killgore, Peter Bradley, Yan Chen, Ke An, Andrew Slifka
Interrupted tensile tests were performed on an AISI 4130 pressure vessel steel and investigated by neutron diffraction and scanning microscopy techniques. Analysis of the neutron diffraction patterns reveal a partitioning of ferrite and martensite phases

Determining Steel Weld Qualification and Performance for Hydrogen Pipelines: Phase I Report

May 23, 2023
Author(s)
Matthew Connolly, May Ling Martin, Zack Buck, Newell Moser, Enrico Lucon, Damian Lauria, Peter Bradley, Andrew Slifka, Robert Amaro
This report details the results of Phase I of the DOT/PHMSA sponsored work on "Determining Steel Weld Qualification and Performance for Hydrogen Pipelines". In this work, the goals of Phase I were 1) to perform a literature review of steel weld

Strain-life performance in hydrogen of DOT pressure vessel steel

November 7, 2022
Author(s)
May Ling Martin, Peter Bradley, Damian Lauria, Robert L. Amaro, Matthew Connolly, Andrew Slifka
Strain-life testing of a 4130 pressure vessel steel was conducted in air and in a high-pressure gaseous-hydrogen environment. Hydrogen causes an order of magnitude decrease in lifetime compared to in-air performance at the same strain-amplitudes. This

High Energy X-Ray Diffraction and Small-Angle Scattering Measurements of Hydrogen Fatigue Damage in AISI 4130 Steel

June 4, 2022
Author(s)
Matthew Connolly, May Ling Martin, Peter Bradley, Damian Lauria, Andrew Slifka, Jun-Sang Park, Robert Amaro, Jonathan Almer
Accurate lifetime predictions are critical for repurposing existing pipelines for hydrogen transmission as well as for developing novel steels which are minimally susceptible to lifetime degradation by hydrogen. Ultimately, lifetime prediction models

Evaluating a Natural Gas Pipeline Steel for Blended Hydrogen Service

March 19, 2022
Author(s)
May Ling Martin, Matthew Connolly, Zack Buck, Peter Bradley, Damian Lauria, Andrew Slifka
An X70 natural gas pipeline steel that is being considered for blended natural gas/hydrogen gas service was evaluated in a high-pressure hydrogen gas environment. Fracture toughness testing and fatigue crack growth rate testing were conducted according to

Materials Testing in Hydrogen

November 30, 2021
Author(s)
Matthew Connolly, May Ling Martin, Damian Lauria, Peter Bradley, Zack Buck, Andrew Slifka, Robert L. Amaro

Experimental study of shear and tensile properties of LIGA Ni-Fe and Ni-Co alloys at quasi-static and intermediate strain rates

April 1, 2021
Author(s)
Li-Anne Liew, David T. Read, May Martin, Todd R. Christenson, Peter E. Bradley, Nicholas Barbosa, Frank W. DelRio, John T. Geaney, Jeffrey Smyth
We report the in-plane shear properties, to fracture, of 200 um-thick LIGA nanocrystalline Ni- 10%Fe and micrograined Ni-10%Co. Planar simple shear specimens were designed, fabricated and pulled to fracture using a miniature commercial tension test stage

Characteristics and Mechanisms of Hydrogen-Induced Quasi-Cleavage Fracture of Lath Martensitic Steel

January 10, 2021
Author(s)
Lawrence Cho, Peter E. Bradley, Damian S. Lauria, May L. Martin, Matthew J. Connolly, Jake Benzing, Eun Jung Seo, Kip O. Findley, John G. Speer, Andrew J. Slifka
This study presents an in-depth characterization of the microstructures, crystallographic orientations, and dislocation characteristics beneath the hydrogen-induced quasi-cleavage features of an as-quenched, lath martensitic (') 22MnB5 steel. The fracture

Elastic-plastic properties of mesoscale electrodeposited LIGA nickel alloy films: microscopy and mechanics

November 22, 2020
Author(s)
Li-Anne Liew, David T. Read, May Martin, Frank W. DelRio, Peter E. Bradley, Nicholas Barbosa, Todd R. Christenson, John T. Geaney
The elastic-plastic properties of mesoscale electrodeposited LIGA Ni alloy specimens are investigated as a function of specimen size, strain rate, and material composition. Two material compositions are studied: a high-strength fine-grained Ni-Fe alloy and

HEXRD Measurement of Strain and Dislocation Density ahead of Crack Tips Grown in Hydrogen

September 13, 2019
Author(s)
Matthew J. Connolly, May L. Martin, Peter E. Bradley, Damian S. Lauria, Andrew J. Slifka, Jun Sang Park, Robert Amaro
The deformation fields near fatigue crack tips grown in hydrogen and in air were measured using high-energy x-ray diffraction. A larger magnitude of elastic strain was observed in the hydrogen case compared to the air case. The magnitude of elastic strain

Demonstration of a Chamber for Strain Mapping of Steel Specimens Under Mechanical Load in a Hydrogen Environment by Synchrotron Radiation

June 4, 2018
Author(s)
Matthew J. Connolly, Peter E. Bradley, Damian S. Lauria, Andrew J. Slifka, Elizabeth S. Drexler
We present a demonstration of a chamber for diffraction measurements of lattice strain for specimens in hydrogen gas under mechanical load. The chamber is suitable for static and cyclic mechanical loading. Synchrotron x-ray radiographs of a fatigue crack

In Situ Neutron Transmission Bragg Edge and Synchrotron X-Ray Measurement of Strain Fields Near Fatigue Cracks Grown in Hydrogen

April 18, 2018
Author(s)
Matthew J. Connolly, Peter E. Bradley, Damian S. Lauria, Andrew J. Slifka, Elizabeth S. Drexler
The embrittlement and enhanced fatigue crack growth rate of metals in the presence of hydrogen is a long-standing problem. In an effort to determine the dominate damage mechanism behind hydrogen assisted fatigue crack growth, we performed High-Energy X-ray