Flexural and thermomechanical properties of the epoxy-based carbon fiber composites (CFCs) on addition of single and binary nanoparticles (nanoclay and graphene) have been investigated. It was found that nanoclay acts more effectively in increasing the stiffness of the CFCs, whereas graphene is more effective in achieving higher strength. Nanoclay-added samples exhibited highest flexural (64.5 GPa) and storage (25.3 GPa) modulus among all types. Graphene-added samples showed highest improvement (by 21%) in flexural strength and exhibited most stable thermomechanical properties with highest energy dissipation capability (3.1 GPa loss modulus) in flexural test and dynamic mechanical analysis (DMA), respectively. By contrast, addition of binary nanoparticles reduced the stiffness and significantly increased the strain to failure (42%) of the composites. Optical microscopy and scanning electron microscopy indicated that addition of nanoparticles significantly reduced delamination and matrix cracking of the CFCs because of strong interfacial bonding and toughened matrix, respectively.

The initial steps of the thermal chemistry of Cu(I)-2-(tert-butylimino)-5,5-dimethyl-pyrrolidinate on metal surfaces were characterized using temperature-programmed desorption experiments and density functional theory (DFT). The relative stability of the initial dimer relative to its dissociation on metal surfaces was evaluated. Several molecular desorption temperatures were identified on Ni(110), but all correspond to dimers, either containing the initial Cu ions or after their removal; no monomer was ever detected. DFT calculations also indicated preferential bonding on Cu(110) as a dimer, albeit with a distorted configuration, via the Cu atoms and in registry with the lattice of the substrate. A potential dissociation pathway of the adsorbed dimer was identified involving the partial detachment of the ligands via the scission of one Cu–N bond at the time and migration to adjacent surface sites. This process is accompanied by the reduction of the Cu centers of the metal–organic complex, indicating that it may be the rate-limiting reaction that leads to further fragmentation of the ligands.

This paper demonstrates the application of Natural Language Processing (NLP) tools to explore large libraries of documents and to correlate heuristic associations between text descriptions in figure captions with interpretations of images and figures. The use of visualization tools based on NLP methods permits one to quickly assess the extent of the research described in the literature related to a specific topic. The authors demonstrate how the use of NLP methods on only the figure captions without having to navigate the entire text of a document can provide an accelerated assessment of the literature in a given domain.

Mo, Zr, and Y with low diffusion coefficients in Al matrix were used to improve the high-temperature properties of the Al–5.8Cu–0.3Mn–0.2Mg alloy. The effects of these microalloying elements on the microstructures of the Al–5.8Cu–0.3Mn–0.2Mg alloy were investigated with the aid of optical microscopy and high-resolution transmission electron microscope (HRTEM). The HRTEM images and selected area electron diffraction patterns indicated that L12-Al3(Zr, Y), Al3Zr, Al3Y, and Al12Mo could precipitate in the process of solid solution treatment after adding Mo, Zr, and Y. These Mo-, Zr-, and Y-containing precipitates were stable at high temperatures and could slow the coarsening rate of θ′ precipitates at high temperatures. The tensile strength of the Al–5.8Cu–0.3Mn–0.2Mg alloy modified by Mo, Zr, and Y microalloying elements was improved significantly at both room and high temperatures. The strengthening mechanisms were discussed in detail.

Graphite nitride carbon nanosheets have received more and more attention toward the photocatalytic research and applications. Ultrathin g-CN nanosheets with porous structure were synthesized successfully by thermal calcination of melamine supramolecular complexes, which was obtained by pre-treating melamine in nitric acid solution at different concentrations (0.5–2 mol/L). Effects of HNO3 pre-treatment on the microstructure of supramolecular complexes were studied. The characteristics of g-CN nanosheets were investigated by X-ray diffractometry, X-ray photoelectron spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The degradation performance for RhB and water splitting hydrogen production performance were used to evaluate the photocatalytic performances of g-CN nanosheets. The morphology and microstructure of HNO3/melamine supramolecular complexes are different from those of melamine precursor due to the better arrangement of the melamine units. Ultrathin porous g-CN nanosheets which possess a thickness of less than 2 nm were successfully prepared by calcination of melamine pre-treated with 1.0 mol/L nitric acid. The g-CN(1.0) nanosheets possess the highest photocatalytic degradation performance and water splitting hydrogen production performance due to the effective separation of photogenerated carriers and high specific surface area providing a large number of active sites.

For achieving flame-retardant AZX912 magnesium alloy with superior mechanical properties, cast ingots were solution-treated at different temperatures of 420–525 °C prior to extrusion at 280 °C. With increasing solution treatment temperature, brittle Al2Ca intermetallic compound changed from a network-like morphology to a spheroidized shape, with an increase in hardness and became unbroken during extrusion. As the solution treatment temperature increased, cracking of Al2Ca particles during tensile deformation tended to be restricted due to hardening and spheroidizing behaviors, and tensile elongation of extruded alloys significantly enhanced from 11.2 to 19.2%. High mechanical strength was maintained with an improvement in ductility when increasing the solution treatment temperature up to 510 °C. The extruded alloy solution-treated at 510 °C exhibited a superior balance between mechanical strength and ductility, with a high ultimate tensile strength of 367 MPa and a good elongation of 16.8%.

Deformation twins have a major role in the microstructure evolution of hexagonal close packed (HCP) metals. Voids are common defects in metals and have a significant impact on their properties. In this work, using molecular dynamics, a tension simulation of single-crystal titanium (Ti) with different void sizes under uniaxial stress conditions was performed. The results showed that the evolution and dominance of the $\left\{ {10\bar{1}2} \right\}$ twin system using the Henning potential was not consistent with the Schmid criterion when the single-crystal Ti contained void defects. From a microscopic perspective, the authors analyzed the relationship between the nucleation and growth of twins and the emission of dislocation loops. The authors found that the existence of voids not only contributes to the emission of dislocation loops but also hinders the movement of these loops. With the increase in void size, the peak dislocation density of ${1 \over 3}\left\langle {\bar{1}100} \right\rangle$ partial dislocation loops decreased. This work is helpful to further investigate the nucleation and evolution of tension twins and to form an effective growth criterion for twins to study the twinning process of HCP metals during plastic deformation.

This work established the feasibility of flexible solution-processed radiation sensors prepared from an organic scintillator (1-phenyl-3-mesityl-2-pyrazoline) and a biocompatible semiconducting polymer (violanthrone-79). Absorbance, steady-state, and time-resolved photoluminescence measurements demonstrated a high efficiency for the transfer of absorbed energy from the scintillator to the semiconductor. Blended nanoparticles containing both materials were fabricated in order to reduce the intermolecular distance between molecules, creating a highly efficient energy transfer pathway. Radiation-sensing devices were then constructed from the materials. These exhibited successful sensitivity for gamma radiation from a 137Cs source that was not present for the control semiconducting polymer alone.

This article examines two intertwined topics on architected materials with imperfections—their mechanics and optimum design. We first discuss the main factors that control defect sensitivity along with a range of strategies for defect characterization. The potency of both as-designed and as-manufactured defects on their macroscopic response is highlighted with an emphasis on those caused by additive manufacturing technology. As a natural extension of defect sensitivity, we describe the design approaches for architected materials with particular focus on systematic tools of topology optimization. Recent extensions to formally incorporate imperfections in the optimization formulation are discussed, where the ultimate goal is to generate architectures that are flaw-tolerant and perform robustly in the presence of imperfections. We conclude with an outlook on the field, highlighting potential areas of future research.

The effort to develop metallic alloys with increased structural strength and improved radiation performance has focused on the incorporation of either solute elements or microstructural inhomogeneities to mitigate damage. The recent discovery and development of single-phase concentrated solid-solution alloys (SP-CSAs) has prompted fundamental questions that challenge established theories and models currently applicable to conventional alloys. The current understanding of electronic and atomic effects, defect evolution, and microstructure progression suggests that radiation energy dissipates in SP-CSAs at different interaction strengths via energy carriers (electrons, phonons, and magnons). Modification of electronic- and atomic-level heterogeneities and tailoring of atomic transport processes can be realized through tuning of the chemical complexity of SP-CSAs by the selection of appropriate elements and their concentrations. Fundamental understanding of controlling energy dissipation via site-to-site chemical complexity reveals new design principles for predictive discovery and guided synthesis of new alloys with targeted functionalities, including radiation tolerance.

Architected materials are a unique and emerging class of materials where performance is fundamentally controlled by geometry at multiple length scales, from the nano- to the macroscale, rather than chemical composition alone. As a result, the realization of these remarkable materials is contingent upon the ability to faithfully reproduce the designed architecture. This presents fundamental challenges in fabrication due to the required three-dimensional complexity, multiple length scales, range of material constituents, possibility of multiple materials in a single architecture, and overall manufacturing throughput. Additive manufacturing (AM) processes can provide solutions to some of these challenges and are discussed in this article. Specifically, light-based and extrusion-based processes and associated materials are presented with an emphasis on recent developments, including volumetric additive manufacturing, and on-the-fly mixing of materials in extrusion-based printing systems. While remarkable advancements have been made in AM for architected materials, bringing these materials and processes to industrial realization remains a significant challenge.