Extraordinary hardening-by-annealing in bulk ultrafine grained magnesium with ultra-low yttrium addition

Zheng, R.*; Gong, W.; 6 of others*

Acta Materialia, 293, p.121098_1 - 121098_12, 2025/07

https://doi.org/10.1016/j.actamat.2025.121098

Complementary layer thickness effects of Q235 and SUS304 layers of multilayered steels for improving of tensile strength and plasticity simultaneously

Lin, Z. M.*; Liu, B. X.*; Ming, K. S.*; Xu, P. G.; Yin, F. X.*; Zheng, S. J.*

Scripta Materialia, 263, p.116692_1 - 116692_7, 2025/07

https://doi.org/10.1016/j.scriptamat.2025.116692

On the role of austenite stability in yielding behavior of a medium Mn steel with a duplex austenite-martensite microstructure

Wang, Y.*; Gong, W.; Harjo, S.; 7 of others*

Acta Materialia, 288, p.120840_1 - 120840_14, 2025/04

https://doi.org/10.1016/j.actamat.2025.120840

Characteristic deformation microstructure evolution and deformation mechanisms in face-centered cubic high/medium entropy alloys

Yoshida, Shuhei*; Gong, W.; 9 of others*

Acta Materialia, 283, p.120498_1 - 120498_15, 2025/01

https://doi.org/10.1016/j.actamat.2024.120498

Effect of carbon segregation at prior austenite grain boundary on hydrogen-related crack propagation behavior in 3Mn-0.2C martensitic steels

Okada, Kazuho*; Shibata, Akinobu*; Kimura, Yuji*; Yamaguchi, Masatake; Ebihara, Kenichi; Tsuji, Nobuhiro*

Acta Materialia, 280, p.120288_1 - 120288_14, 2024/11

https://doi.org/10.1016/j.actamat.2024.120288

Anomalous dislocation response to deformation strain in CrFeCoNiPd high-entropy alloys with nanoscale chemical fluctuations

Ying, H.*; Yang, X.*; He, H.*; Yan, A.*; An, K.*; Ke, Y.*; Wu, Z.*; Tang, S.*; Zhang, Z.*; Dong, H.*; et al.

Scripta Materialia, 250, p.116181_1 - 116181_7, 2024/09

https://doi.org/10.1016/j.scriptamat.2024.116181

Control of twin boundary mobility by solute segregation in Mg binary alloys

Somekawa, Hidetoshi*; Tsuru, Tomohito; Naito, Kimiyoshi*; Singh, A.*

Scripta Materialia, 249, p.116173_1 - 116173_6, 2024/08

https://doi.org/10.1016/j.scriptamat.2024.116173

The segregated twin boundaries play a role in obstruction of dislocation slips. Thus, they contribute to increase in hardness. Internal friction tests reveal that, irrespective of the solute elements, induced twin boundaries are effective in enhancing damping capacity, owing to their reversible motion, i.e., growth and shrinkage. In contrast, by comparison of the loss factor of specimens with/without twin boundary segregation, segregation leads to a decrease in damping capacity. The energy barrier required for twin boundary sliding to occur is closely related to the loss factor.

Combining muon spin relaxation and DFT simulations of hydrogen trapping in AlMn

Shimizu, Kazuyuki*; Nishimura, Katsuhiko*; Matsuda, Kenji*; Akamaru, Satoshi*; Nunomura, Norio*; Namiki, Takahiro*; Tsuchiya, Taiki*; Lee, S.*; Higemoto, Wataru; Tsuru, Tomohito; et al.

Scripta Materialia, 245, p.116051_1 - 116051_6, 2024/05

https://doi.org/10.1016/j.scriptamat.2024.116051

Hydrogen at the mass ppm level causes hydrogen embrittlement in metallic materials, but it is extremely difficult to experimentally elucidate the hydrogen trapping sites. We have taken advantage of the fact that positive muons can act as light isotopes of hydrogen to study the trapping state of hydrogen in matter. Zero-field muon spin relaxation experiments and the density functional theory (DFT) calculations for hydrogen trapping energy are carried out for AlMn. The DFT calculations for hydrogen in AlMn have found four possible trapping sites in which the hydrogen trapping energies are 0.168 (site 1), 0.312 (site 2), 0.364 (site 3), and 0.495 (site 4) in the unit of eV/atom. Temperature variations of the deduced dipole field width () indicated step-like changes at temperatures, 94, 193, and 236 K. Considering their site densities, the observed change temperatures are interpreted by trapping muons at sites 1, 3, and 4.

Stress corrosion cracking induced by the combination of external and internal hydrogen in Al-Zn-Mg-Cu alloy

Tang, J.*; Wang, Y.*; Fujihara, Hiro*; Shimizu, Kazuyuki*; Hirayama, Kyosuke*; Ebihara, Kenichi; Takeuchi, Akihisa*; Uesugi, Masayuki*; Toda, Hiroyuki*

Scripta Materialia, 239, p.115804_1 - 115804_5, 2024/01

https://doi.org/10.1016/j.scriptamat.2023.115804

Stress corrosion cracking (SCC) behaviors induced by the combination of external and internal hydrogen (H) in an Al-Zn-Mg-Cu alloy were systematically investigated via in situ 3D characterization techniques. SCC of the Al-Zn-Mg-Cu alloy could initiate and propagate in the potential crack region where the H concentration exceeded a critical value, in which the nanoscopic H-induced decohesion of -MgZn precipitates resulted in macroscopic cracking. External H that penetrated the alloy from the environment played a crucial role during the SCC of the Al-Zn-Mg-Cu alloy by generating gradient-distributed H-affected zones near the crack tips, which made Al alloys in water environment more sensitive to SCC. Additionally, the pre-existing internal H was driven toward the crack tips during plastic deformation. It was involved in the SCC and made contributions to both the cracks initiation and propagation.

Ionic radii in fluorites

Vauchy, R.; Hirooka, Shun; Murakami, Tatsutoshi

Materialia, 32, p.101934_1 - 101934_12, 2023/12

https://doi.org/10.1016/j.mtla.2023.101934