Search Results

You searched for all publications:

with publication states 'Published (Approved)'

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

Exact matches
Related results

3 items found (0 items not approved), displaying all items.1

Instruments / Technical Area	Publication Details	Published
E02-JEM ARM 300CF	The mechanism of twin thickening and the elastic strain state of TWIP steel nanotwins Thomas W. J. Kwok , T. P. Mcauliffe , A. K. Ackerman , B. H. Savitzky , M. Danaie , C. Ophus , D. Dye Materials Science And Engineering: A 324 DOI: 10.1016/j.msea.2023.145005 Diamond Proposal Number(s): [18770] Open Access Show Abstract ▼ Abstract: A Twinning Induced Plasticity (TWIP) steel with a nominal composition of Fe-16.4Mn-0.9C-0.5Si-0.05Nb-0.05V was deformed to an engineering strain of 6%. The strain around the deformation twins were mapped using the 4D-STEM technique. Strain mapping showed a large average elastic strain of approximately 6% in the directions parallel and perpendicular to the twinning direction. However, the large average strain comprised of several hot spots of even larger strains of up to 12%. These hot spots could be attributed to a high density of sessile Frank dislocations on the twin boundary and correspond to shear stresses of 1–1.5 GPa. The strain and therefore stress fields are significantly larger than other materials known to twin and are speculated to be responsible for the early thickness saturation of TWIP steel nanotwins. The ability to keep twins extremely thin helps improve grain fragmentation, i.e. the dynamic Hall-Petch effect, and underpins the large elongations and strain hardening rates in TWIP steels.	Apr 2023
	Robust measurements of functional material properties using in situ 4D-STEM Colin Ophus , Michele Conroy , Mohsen Danaie , Benjamin H. Savitzky , Alexander Rakowski , Abigail Ackerman , Steven E. Zeltmann , Jim Ciston , Andrew M Minor , David Dye Microscopy And Microanalysis 28, 2312 - 2313 Microscopy & Microanalysis 2022: P09 - Insights into Phase Transitions in Functional Materials by in situ/operando TEM: Experiment Meets Theory DOI: 10.1017/S1431927622008881 Show Abstract ▼ Abstract: Conventional scanning transmission electron microscopy (STEM) imaging experiments record only a few values per probe position, generating bright field or dark field images, consisting of unscattered or scattered electrons respectively. The contrast in these images is highly sensitive to changes in local structure and the resolution is sufficient to resolve individual atoms. Unfortunately, many real-world samples in materials science studies are too thick or too complex to easily measure the structural properties of interest in this manner. An alternative to conventional STEM imaging is to use a high-speed direct electron detector, which records a full image (2D data) of the diffracted electron probe scanned over the sample (2D grid of positions), producing a four-dimensional measurement known as 4D-STEM. These 4D-STEM measurements of millions of diffraction patterns are extremely rich in information, but require efficient and robust software in order to measure sample properties. We have developed the py4DSTEM open source analysis toolkit to perform these analyses.	Aug 2022
E02-JEM ARM 300CF	In situ analysis of nm-scale alpha formation in titanium alloys A. K. Ackerman , C. Ophus , M. Danaie , P. Karamched , A. J. Knowles , A. Wilkinson , D. Rugg , D. Dye Microscopy And Microanalysis 25, 1490 - 1491 Microscopy & Microanalysis 2019: P01 - In situ TEM Characterization of Dynamic Processes During Materials Synthesis and Processing DOI: 10.1017/S1431927619008183 Diamond Proposal Number(s): [18190]	Aug 2019

Publications Database

Search Results

You searched for all publications:

Search Again...

Subject Areas (check all that apply) select all

Instruments used to collect data (check all that apply) select all

Collaborations involved (check all that apply) select all

Diamond Offline Facilities used

Relevant Technical Areas (check all that apply) select all

Menu for Anonymous User