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The main focus of this work is to investigate the impact of varying milling times (2 to 18 h) on the structural and mechanical properties of the developed Ti-Nb-Mo alloy. The morphology, phase composition, microstructure, and mechanical behavior of milled and sintered Ti-25Nb-25Mo alloy samples were characterized systematically using x-ray diffraction, scanning electron microscope, optical microscope, and Vicker microhardness. It was noted that the quantity of the β-Ti phase increased as the milling time increased. After 12 h of milling, the synthesized alloys exhibited a spherical morphology and texture with homogeneous distribution. The milled alloys' structural evolution and morphological changes were found to be dependent on their milling duration. Morphological analysis revealed that the crystallite size and mean pore size decreased when the milling duration increased, reaching minimum values of 51 nm and < 1 μm, after 12 and 18 h respectively. As the milling time increased, the grain size decreased, resulting in an increase in density, microhardness, and elastic modulus. Ti-25Nb-25Mo will presents good anti-wear ability and higher resistance to plastic deformation due to enhanced mechanical characteristics (H/E, and H3/E2). Hence, the developed Ti-25Nb-25Mo alloys with reduced elastic modulus and desirable mechanical properties were found to be a promising option for biomedical applications.

This paper is a collection of selected contributions of the 1st International Workshop on Mechanochemistry of Metal Hydrides that was held in Oslo in May 2018. In this paper, the recent developments in the use of mechanochemistry to synthesize and modify metal hydrides are reviewed. A special emphasis is made on new techniques beside the traditional way of ball milling. High energy milling, ball milling under hydrogen reactive gas, cryomilling and severe plastic deformation techniques such as High-Pressure Torsion (HPT), Surface Mechanical Attrition Treatment (SMAT) and cold rolling are discussed. The new characterization method of in-situ X-ray diffraction during milling is described.

Ball-end cutters are widely used in industries of dies, molds, and aerospace, which have the problem of poor machined surface quality due to the low cutting speed near the tool-tip. With the increase in the complexity of parts, it will become more and more difficult to avoid the tool-tip participating in the cutting. In this paper, the velocity effect sensitivity of the ball-end cutter is analyzed, and several key positions, including the intersection points of the CWE boundaries, are selected to describe the cutting speed in three dimensions. The relationships between the cutting speed of the critical points and important variables such as the machining inclination angle and the feed direction were investigated. The optimal range of feed direction is obtained when the tool-tip engages in the contact circle. The core aim of the feed direction selection is to make the tool engagement area in a high position by changing the feed direction, to avoid surface damage and improve the quality of the machined surface. Finally, an experimental study was carried out, and the results corroborate the effectiveness of the selection method. In the experiment, it was also found that cutting-out from the cutter contact position can improve the surface quality in the directions of non-optimal range, and the milling force and chips shape will vary with the change of the feed direction.

Magnesium hydride and selected magnesium-based ternary hydride (Mg2FeH6, Mg2NiH4, and Mg2CoH5) syntheses and modification methods, as well as the properties of the obtained materials, which are modified mostly by mechanical synthesis or milling, are reviewed in this work. The roles of selected additives (oxides, halides, and intermetallics), nanostructurization, polymorphic transformations, and cyclic stability are described. Despite the many years of investigations related to these hydrides and the significant number of different additives used, there are still many unknown factors that affect their hydrogen storage properties, reaction yield, and stability. The described compounds seem to be extremely interesting from a theoretical point of view. However, their practical application still remains debatable.

Electromagnetic (EM) wave absorption performance is greatly affected by the microscopic morphology of the absorbing material particles. In this study, a facile and efficient ball-milling method was applied to increase the aspect ratio of particles and prepare flaky carbonyl iron powders (F-CIPs), one of the most readily commercially available absorbing materials. The effect of ball-milling time and rotation speed on the absorption behaviors of the F-CIPs was investigated. The microstructures and compositions of the F-CIPs were determined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The EM parameters were measured using a vector network analyzer (VNA) in the frequency range of 2–18 GHz. The results indicated that the ball-milled flaky CIPs exhibited a better absorption ability than the raw spherical CIPs. Among all the samples, the sample milled at 200 r/min for 12 h and the sample milled at 300 r/min for 8 h showed remarkable EM parameters. The ball-milling sample with 50 wt.% F-CIPs had a minimum reflection loss peak of −14.04 dB at a thickness of 2 mm and a maximum bandwidth (RL < −7 dB) of 8.43 GHz at a thickness of 2.5 mm, a result that conformed with the transmission line theory. Hence, the ball-milled flaky CIPs were considered to be beneficial for microwave absorption.

Throughout human history, any society’s capacity to fabricate and refine new materials to satisfy its demands has resulted in advances to its performance and worldwide standing. Life in the twenty-first century cannot be predicated on tiny groupings of materials; rather, it must be predicated on huge families of novel elements dubbed “advanced materials”. While there are several approaches and strategies for fabricating advanced materials, mechanical milling (MM) and mechanochemistry have garnered much interest and consideration as novel ways for synthesizing a diverse range of new materials that cannot be synthesized by conventional means. Equilibrium, nonequilibrium, and nanocomposite materials can be easily obtained by MM. This review article has been addressed in part to present a brief history of ball milling’s application in the manufacture of a diverse variety of complex and innovative materials during the last 50 years. Furthermore, the mechanism of the MM process will be discussed, as well as the factors affecting the milling process. Typical examples of some systems developed at the Nanotechnology and Applications Program of the Kuwait Institute for Scientific Research during the last five years will be presented in this articles. Nanodiamonds, nanocrystalline hard materials (e.g., WC), metal-matrix and ceramic matrix nanocomposites, and nanocrystalline titanium nitride will be presented and discussed. The authors hope that the article will benefit readers and act as a primer for engineers and researchers beginning on material production projects using mechanical milling.

The control variable method is a method to study the influence of a certain factor on the result quantity by artificially controlling other factors. Some researches have shown that a micro-texture can effectively reduce the surface work-hardening degree of the tool surface. Therefore, in this study, based on the control variable method, a micro-texture ball-end milling cutter was used to mill titanium alloy. The influence rules of micro-texture distance from edge, micro-texture distribution type and mode and cutting stroke on work hardening degree were analysed. The results show that the surface work-hardening degree was the smallest(118%) at a distance of 90 μm from the cutting edge and at a 0.3° offset angle. When the micro-texture is micro-pit texture, the work hardening degree is 121% and is minimum. The content of the O element in the surface modification layer of the micro-textured tool is 6.97%, which is less than 16.17% of that of the non-textured tool, and the content of the C element is 4.95% and 4.97% respectively. The results show that the micro-texture placement can effectively reduce the oxidation degree and work hardening degree of the machined surface of the milled titanium alloy.

Phosphorus (P) possesses the highest theoretical specific capacity (865 mA h g−1) among all the elements for potassium‐ion battery (PIB) anodes. Although Red P (RP) has intrinsic advantages over its allotropes, including low cost and nontoxicity, and simpler preparation, it is yet unknown to effectively activate it into a high‐performance PIB anode. Here, high‐performance RP PIB anodes are reported. Two important factors are found to facilitate RP react with K‐ions reversibly: i) nanoscale RP particles are dispersed evenly in a conductive carbon matrix composed of multiwall carbon nanotubes and Ketjen black that provide an efficient electrical pathway and a tough scaffold. ii) The results of X‐ray photoelectron spectroscopy spectrum and the electrochemical performance perhaps show that no PC bond formation is beneficial to allow K‐ions to react with RP effectively. As a result, the RP/C electrodes deliver a reversible specific capacity of ≈750 mA h g−1 and exhibit a high‐rate capability (≈300 mA h g−1 at 1000 mA g−1). RP/C full cells using potassium manganese hexacyanoferrate as cathode show a long cycling life (680 cycles) at a current density of 1000 mA g−1, in addition, a pouch‐type battery is built to demonstrate practical applications. Red phosphorus (RP) is activated for potassium‐ion battery anodes via a facile wet‐ball milling process. Supported by the conductive network composed of multiwall carbon nanotubes and Ketjen black, full cells comprising an RP/C anode and a potassium manganese hexacyanoferrate cathode show a high specific energy density (193 Wh kg−1) that is a high value for K‐ion full cells.

This review aims to expose mechanical milling as an alternative method for generating copper-based particles (copper particles (CuP) and copper composites (CuC)); more specifically, via a top-down or bottom-up approach, on a lab-scale. This work will also highlight the different parameters that can affect the size distribution, the type, and the morphology of the obtained CuP or CuC, such as the type of mechanical mill, ball-to-powder ratios (BPR), the milling speed, milling time, and the milling environment, among others. This review analyzes various papers based on the Cu-based particle generation route, which begins with a pretreatment step, then mechanical milling, its approach (top-down or bottom-up), and the post-treatment. Finally, the characterization methods of the resulting CuP and CuC through mechanical milling are also discussed.

The use of blisk is essential for improving the performance of aviation engines, and the cutting of blade curved surface is the core of blisk CNC machining. In response to the problem of traditional ball end milling cutter and barrel milling cutter that is difficult to take into account the quality and efficiency of blade machining, this article proposes a barrel-taper-ball milling cutter. The contour of the new cutter’s barrel taper area is more fit with the blade curved surface, which is conducive to obtaining a larger cutting step and a tiny scallop height. Further, for the problem of weak rigidity thin-wall curved surface machining chatter, the cutting dynamics model of the five-axis machining of the barrel-taper-ball milling cutter is established. Through the determination of the material contact criterion of cutting edge micro element, a cutting geometry analysis algorithm is proposed. By deducing the oblique cutting forces of barrel taper area and ball end area, exploring the time-varying characteristics of blade modes, the multiple frequently method theory is extended to construct the stability machining parameter domain. Experiments and simulations indicate that the cutting step of the new cutter under the same surface roughness can increase by seven times, the solution error of cutting geometry on blade curved surface is only 0.5%, the prediction error of three-dimensional cutting force is about 4.95%, and the optimized stability parameter domain can achieve machining without chatter.