Results 71 to 80 of about 10,394 (267)

Wolf-Rayet stellar evolution models with improved treatment of the atmosphere

Astronomy & Astrophysics
Context. Evolutionary models of massive stars are quasi-exclusively computed using an Eddington gray atmosphere. This approximation does not accurately describe the complex physical phenomena occurring in the atmosphere of massive stars. Aims.
Voje Thomas, Palacios Ana, Martins Fabrice   +2 more
doaj   +1 more source

The Formation of Very Massive Stars in Early Galaxies and Implications for Intermediate Mass Black Holes

The Open Journal of Astrophysics, 2020
We investigate the ab-initio formation of super-massive stars in a pristine atomic cooling halo. The halo is extracted from a larger self-consistent parent simulation.
John A. Regan, John H. Wise, Tyrone E. Woods, Turlough P. Downes, Brian W. O'Shea, Michael L. Norman   +5 more
doaj   +1 more source

Current Status and Challenges in Data Collection for Aerospace Coatings Deposited by Plasma Spraying

Advanced Engineering Materials, EarlyView.
An innovative approach has been integrated into the GRENAT project to optimize plasma spraying and coating performance. Raw materials are accelerated and melted in the plasma generated by torches, creating coatings. Monitoring sensors collect process data which are combined with ex situ characterization data.
Lila Randriamananjara, Vincent Rat, Quentin Dubreuil, Patrice Valorge, Simon Goutier, Alain Denoirjean, Olivier Messe, Céline Ruelle, Jean‐Philippe Poli   +8 more
wiley   +1 more source

In Situ Micromechanical Study of Bimodal γ′–γ″ Precipitate Assemblies in Ni–Cr–Al–Nb Superalloy

Advanced Engineering Materials, EarlyView.
A Ni–Cr–Al–Nb superalloy with a bimodal γ′–γ″ precipitate distribution is developed. Composite precipitate assemblies form through heterogeneous nucleation, effectively impeding dislocation motion. Micropillar compression reveals high strength at room and elevated temperatures, governed by precipitate shearing, with coupled faulting mechanisms ...
Ujjval Bansal, Tae‐Hyeok Kang, Pyuck‐Pa Choi, Subin Lee, Christoph Kirchlechner   +4 more
wiley   +1 more source

Supernovae from Massive Stars [PDF]

, 2017
Massive stars, by which we mean those stars exploding as core collapse supernovae, play a pivotal role in the evolution of the Universe. Therefore, the understanding of their evolution and explosion is fundamental in many branches of physics and astrophysics, among which, galaxy evolution, nucleosynthesis, supernovae, neutron stars and pulsars, black ...
openaire   +3 more sources

Grain Refinement During Severe Plastic Deformation and Similitude of Subgrain Formation: A Molecular Dynamics Study

Advanced Engineering Materials, EarlyView.
Molecular dynamics is used to investigate structure refinement during severe plastic deformation. The results show similitude with experimental data. Molecular dynamics simulations of severe plastic deformation of monocrystalline and polycrystalline samples by multiaxial compression of aluminum are carried out.
Roberto B. Figueiredo
wiley   +1 more source

Microstructure, Thermal Transport, and Dry‐Sliding Tribology of Powder‐Metallurgy Al7075 Composites Reinforced With Sol–Gel‐Derived ZnO–rGO Hybrid Nanoparticles

Advanced Engineering Materials, EarlyView.
Sol–gel‐derived ZnO–rGO hybrid nanoparticles enable Al7075 powder‐metallurgy composites to achieve concurrent gains in hardness and thermal conductivity while markedly lowering friction and wear. The hybrid architecture couples ZnO‐based load support with rGO‐assisted lamellar sliding and heat spreading, revealing a promising route toward lightweight ...
Bunyamin Aksakal, Cevher Kursat Macit, Merve Ayık, Hakan Tutumlu   +3 more
wiley   +1 more source

External and Internal Cracking Caused by Heat Treatment in Laser Powder Bed Fusion‐Fabricated Inconel 738LC Components

Advanced Engineering Materials, EarlyView.
Manufacturing problems such as heat treatment‐induced cracking hinder the widespread application of the laser powder bed fusion (LPBF) process to superalloys. In this study, cracks in the LPBF components of Inconel 738LC superalloy are characterized after heat treatment at various temperature ranges, revealing two distinct cracking behaviors.
Kosuke Kuwabara, Masahiro Kusano, Ayako Ikeda, Toshio Osada, Makoto Watanabe   +4 more
wiley   +1 more source

The drastic impact of Eddington-limit induced mass ejections on massive star populations

Astronomy & Astrophysics
Context. Massive stars emit copious amounts of radiation, profoundly affecting their environment in galaxies and contributing to the reionization of the Universe.
Pauli D., Langer N., Schootemeijer A., Marchant P., Jin H., Ercolino A., Picco A., Willcox R., Sana H.   +8 more
doaj   +1 more source

Enhancing Fatigue Crack Growth Resistance in Heterostructured Aluminum Bimetals by Tailored Interface Design

Advanced Engineering Materials, EarlyView.
Different Al/Al bimetals with a single engineered interface reveal how mechanical mismatch governs fatigue crack growth under cyclic loading. Additionally, loading–unloading–reloading tests link the microyielding behavior to the fatigue crack growth resistance, while crack‐path analysis reveals toughening mechanisms at the interface, highlighting ...
Sebastian Vollath, Philip Manuel Pohl, Heinz Werner Höppel   +2 more
wiley   +1 more source