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The history of antimony modification of Al–Si casting alloys is reviewed, together with the important technical and commercial reasons why antimony is no longer used as a modifier. [ABSTRACT FROM AUTHOR]

Paper-based devices enable low-cost mass production, wide availability and useful technical aspects such as light weight, mechanical bendability and natural integration in existing paper-based creations such as educational books, administrative documentation and artwork. While magneto-electronics and spintronics play an important role in delivering sensing, communication and data storage solutions, especially necessary in the framework of the internet of things, it is beneficial to achieve compatibility between this technology and paper materials. As a first example of paper-based magneto-electronics, we investigate the manufacturing of well performing anisotropic magneto-resistors on paper by means of low power sputter deposition of permalloy $$(\hbox {Py:Ni}_{81}\hbox {Fe}_{19})$$ , shadow mask patterning and magnetic clamping of the shadow mask. A range of commercially available papers were studied by varying most significant mechanical, chemical and geometrical attributes of the paper to this application. The dependence of magnetic properties (coercivity, saturation remanence and relative permeability) on the paper properties (surface roughness, stiffness and paper making process) was studied based on magnetic characterization, surface profilometry and elemental analysis. Subsequently, conclusions on the optimal magnetic $$\hbox {Py:Ni}_{81}\hbox {Fe}_{19}$$ -on-paper system were drawn. [ABSTRACT FROM AUTHOR]

Traditional bending products are usually divided into two steps: extrusion and bending. Staggered extrusion (SE) as a new process was proposed to prepare Mg alloy bending products in this paper. By designing the structure at one end of the stem, the dual functions of extrusion process and bending process can be realized in a single extrusion pass. The results of the present study show that by adjusting the degree of deformation of the AZ31 Mg alloy, a bending product with a specific curvature could be obtained by the SE process, and the microstructure of the bending product was refined. When the extrusion ratio was increased from 11.11 to 44.44, the grain size was refined from 23.89 to 9.69 μm, and the percentage of recrystallized structures increased from 61.1 to 78.8%. [ABSTRACT FROM AUTHOR]

Supported Pd catalysts were synthesized using various semiconductor materials by a photo-assisted deposition method under UV-light irradiation. The Pd precursor was deposited and partially reduced by the direct interaction with the photo-excited state of the semiconductor materials, and subsequently transformed into metal particles by H2reduction. CO adsorption and Pd K-edge XAFS measurements demonstrated that the mean diameter of the deposited Pd particles can be controlled by the type of employed semiconductor materials. The catalytic activities in the direct synthesis of hydrogen peroxide (H2O2) using H2and O2gases under atmospheric pressure were strongly dependent on the type of supports. Here, the use of TiO2comprising a mixed phase of anatase and rutile was the most efficient based on the amount of Pd. The photo-assisted deposition also provides a simple and straightforward method to synthesize PdAu alloy nanoparticles. For the structural model of PdAu nanoparticles, we suggest that most of the Au atoms are preferentially located in the core region, whereas the Pd atoms are preferentially located in the shell region. The PdAu/TiO2catalysts prepared by the photo-assisted deposition method were shown to perform significantly better than the pure Pd/TiO2catalysts. [ABSTRACT FROM AUTHOR]

High Cr content Ni-Cr-Ti arc-sprayed coatings have been extensively applied to mitigate corrosion in black liquor recovery boilers in the pulp and paper industry. In a previous article, the effects of key spray parameters on the coating's microstructure and its composition were investigated. Three coating microstructures were selected from that previous study to produce a dense, oxidized coating (coating A), a porous, low oxide content coating (coating B), and an optimized coating (coating C) for corrosion testing. Isothermal oxidation trials were performed in air at 550 and 900 °C for 30 days. Additional trials were performed under industrial smelt deposits at 400 and 800 °C for 30 days. The effect of the variation in coating microstructure on the oxidation and smelt's corrosion response was investigated through the characterization of the surface corrosion products, and the internal coating microstructural developments with time at high temperature. The effect of long-term, high-temperature exposure on the interaction between the coating and substrate was characterized, and the mechanism of interdiffusion was discussed. [ABSTRACT FROM AUTHOR]

As a destructive phenomenon with possible detrimental impact especially when it comes to human life, tribocorrosion has always been imperative to be researched. Hence, various investigations have outlined its influential role in the biomaterial apparatuses. Also, disparate routes have been introduced to address this problem. The use of several types of alloys, the application of various types of coatings, and the production of porous layers are some of these efforts made till now. Because of this issue's importance, and lack of a comprehensive review paper in this area of research, this paper shows an overview of existing publications in this area of research. This study presents the important ideas behind studies and provides a perspective of the research trend. In this exploration, the critical elements of the tribocorrosion-related studies were discussed thoroughly. The origin of the problem and the influential parameters in the process like loading, manufacturing, environment, and surface innate oxide film were scrutinized. Also, the efficacy of the use of different alloys, coatings, and the recommended modifications with respect to the tribocorrosion was discovered. We hope that this survey helps promote the emergence of new ideas for future research. [ABSTRACT FROM AUTHOR]

Since the fundamental works of Kachanov and Rabotnov, creep damage mechanics is an established field of research in solid mechanics. The starting point is the creep behavior of materials under moderate loads but elevated temperatures. The final stage of creep behavior is accompanied by damage and other microstructural changes such as embrittlement. In the present paper a detailed analysis of literature is given. A special focus is made on the different types of representation of damage by scalar, vectorial and tensorial variables. In addition, some Russian sources are presented which are not widely known yet. The survey is representative, but not complete - due to the large number of sources, it is not possible to provide a complete overview. Considering the huge number of parameters of tensorial damage variables which should be established experimentally in the second part of the paper a simple model for the high temperature creep and embrittlement in metals and alloys under conditions of the long-term usage is introduced. The model is an extension of R. Arutunyan's model developed in the 90th of the last century. The extension includes the consideration of a compressible medium, the introduction of the mass conservation law and true stress, and definition of the damage parameter as a relative change in the density of the material. The parameters are experimentally estimated and the comparison of simulations and experiments is given. [ABSTRACT FROM AUTHOR]

FeRh-based alloys have attracted significant attention due to their magnetic phase transition and significant magnetocaloric effects. These properties position them as promising candidates for fundamental research and practical applications, including magnetic cooling and targeted drug delivery. The study of FeRh alloys, particularly those where Rhodium or Iron atoms are substituted with other transition metals, is crucial as certain substitutions preserve the alloy's magnetocaloric properties. However, even within a specific structural type and without considering competing phases, determining which atom (Fe or Rh) is replaced upon introducing a third element remains unclear. This paper addresses this ambiguity through ab initio calculations. We propose an approach to predict whether a dopant will replace Fe or Rh, offering insights into the electronic and structural factors influencing the substitution. Additionally, we present a dataset of ab initio calculations on doped FeRh alloys, which will support future data-driven modeling efforts. Our findings not only advance the understanding of FeRh-based alloys but also contribute to the design of novel materials for experimental and industrial applications. [ABSTRACT FROM AUTHOR]

Al and Mg alloy high pressure die castings (HPDC) are increasingly used in automotive industries. The microstructures in the castings have decisive effect on the casting mechanical properties, in which the microstructure characteristics are fundamental for the investigation of the microstructure-property relation. During the past decade, the microstructure characteristics of HPDC Al and Mg alloys, especially micro-pores and α-Fe, have been investigated from two-dimensional (2D) to threedimensional with X-ray micro-computed tomography (μ-CT). This paper provides an overview of the current understanding regarding the 3D characteristics and formation mechanisms of microstructures in HPDC alloys, their spatial distributions, and the impact on mechanical properties. Additionally, it outlines future research directions for the formation and control of heterogeneous microstructures in HPDC alloys. [ABSTRACT FROM AUTHOR]

The article presents a list of papers related to materials science published in volumes 39, 40 and 41 of the periodical. The articles include "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," by A. Baldan, "Thermo-Mechanical Fatigue of Shape Memory Alloys," by E. Hornbogen and "Models in Thermoluminescence," by C. Furetta and G. Kitis.

This paper provides a critical overview of experimental and computational studies conducted on additive manufacturing (AM) or 3D printing using bimetallic alloys. The review acknowledges the complexity introduced by mechanical interactions and significant interface anisotropies in multi-material AM, making the mechanisms of phase change and microstructure evolution more intricate. Various computational models, such as density functional theory (DFT), phase field, and finite element models, employed in the study of 3D printed bimetallic materials are discussed. The paper highlights the importance of future research in developing quantitative predictions that can simulate and forecast microstructure formation during the AM process. By incorporating computational modeling, this review underlines the potential for overcoming challenges associated with the intricate interactions between different materials in multi-material AM (MMAM). [ABSTRACT FROM AUTHOR]

This paper reports on the development and validation of a formal model for an automotive adaptive exterior lights system (ELS) with multiple variants in Alloy 6, which is the most recent version of the Alloy lightweight formal specification language that supports mutable relations and temporal logic. We explore different strategies to address variability, one in pure Alloy and another through an annotative language extension. We then show how Alloy and its Analyzer can be used to validate systems of this nature, namely by checking that the reference scenarios are admissible, and to automatically verify whether the established requirements hold. A prototype was developed to translate the provided validation sequences into Alloy and back to further automate the validation process. The resulting ELS model was validated against the provided validation sequences and verified for most of requirements for all variants. [ABSTRACT FROM AUTHOR]

The article presents a list of several articles on chemistry including "Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials," by A. Baldan, "Thermo-mechanical fatigue of shape memory alloys," by E. Hornbogen, and "Observations of common microstructural issues associated with dynamic deformation phenomena: Twins, microbands, grain size effects, shear bands, and dynamic recrystallization," by L. E. Murr and E. V. Esquivel.

The article presents a list of articles related to materials science published in volumes 39, 40, and 41. The articles include "Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials," "Observations of common microstructural issues associated with dynamic deformation phenomena: Twins, microbands, grain size effects, shear bands, and dynamic recrystal," and "Role of entropy of fusion in phase transformation and selfdiffusion."

The article presents a list of articles published in the "Journal of Materials Science," including "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," "Thermo-Mechanical Fatigue of Shape Memory Alloys," "Role of Entropy of Fusion in Phase Transformation and Self-Diffusion," "Synthetic Routes, Properties and Future Applications of Polymer-Layered Silicate Nanocomposites," and "Models in Thermoluminescence."

Integral blisk blades are typical complex curved structures with small thickness, low stiffness, and complex boundaries. Due to the high material removal rate during the machining process, they are prone to force-induced deformation, resulting in significant machining errors. This seriously contradicts the requirements for high design accuracy and surface accuracy in the aerospace industry. Therefore, accurately predicting the distribution pattern of deformation caused by dynamic milling forces during the machining process and proposing reasonable error compensation strategies are urgent issues to be solved in the manufacturing of integral blisk blade. Firstly, this paper establishes a prediction model for the deformation distribution during the milling process of the integral blisk blade. Secondly, based on the finite element deformation prediction model of blades, the selection of blade milling processing methods and parameters was completed with the goal of minimizing machining deformation. Finally, a reverse reconstruction geometric modeling compensation strategy is proposed, and the tool path program containing the deformation error compensation amount is regenerated. The prediction model and compensation strategy proposed in this paper were validated through milling experiments and profile accuracy measurement experiments on a certain aeroengine integral blisk blade. The results showed that the prediction model has high reliability, with an average error of 7.96%; the new compensation strategy can reduce the tool-yielding error to within the tolerance range. This study will provide technical support for improving the machining accuracy and efficiency of integral blisk blade. [ABSTRACT FROM AUTHOR]

The article presents a list of papers published in the 2004 and 2005 issues of the "Journal of Materials Science." Some of the papers listed are: "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials"; "Role of Entropy of Fusion in Phase Transformation and Self-Diffusion"; "Models in Thermoluminescence"; "Electrical Applications of Carbon Materials"; "Use of Polymers for Cement-Based Structural Materials"; and "Effect of Anions on the Textural and Catalytic Activity of Titania-Silica Mixed Oxide."

The article presents a list of papers published in the vol. 39 and 40 of the "Journal of Materials Science." Some of the papers are, "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," by A. Baldan, "Thermo-Mechanical Fatigue of Shape Memory Alloys," by E. Hornbogen, "Electrical Applications of Carbon Materials," by D.D.L. Chung, and others.

This article presents a list of research papers related to materials science, published in the "Journal of Materials Science." These research papers include "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," by A. Baldan; "Thermo-Mechanical Fatigue of Shape Memory Alloys," by E. Hornbogen; "Role of Entropy of Fusion in Phase Transformation and Self-Diffusion," by G.P. Tiwari, J.M. Juneja and Y. Iijima; "Models in Thermoluminescence," by C. Furetta and G. Kitis; and "Electrical Applications of Carbon Materials," by D.D.L. Chung.

The article presents several review papers published in the Volumes 39 and 40 of the "Journal of Materials Science" including "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," by A. Baldan, "Thermo-Mechanical Fatigue of Shape Memory Alloys," by E. Hornbogen, "Recent Developments in Polyurethane-based Conducting Composites," by J. Njuguna and K. Pielichowski, "A Review of Anode Materials Development in Solid Oxide Fuel Cells," by San Ping Jiang, Siew Hwa Chan, and "Advances in the Study on Wear of Metals by Polymers," by Si-Wei Zhang and Ren-Yang He.

Lists research papers in the volumes 39 and 40 of the "Journal of Materials Science". "Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials," by A. Baldan; "Thermo-mechanical fatigue of shape memory alloys," by E. Hornbogen; "Role of entropy of fusion in phase transformation and self-diffusion," by G.P. Tiwari, J.M. Juneja and Y. Illjima.

Presents review papers in the volumes 39 and 40 of the February 15, 2005 issue of the "Journal of Materials Science". Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials; Thermo-mechanical fatigue of shape memory alloys; Electrical applications of carbon materials,

Lists review papers published in vols. 39 and 40 of the "Journals of Materials Science" publication. "Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials," by A. Baldan; "Thermo-mechanical fatigue of shape memory alloys," by E. Hornbogen; "Models in thermoluminescence," by C. Furette and G. Kitis; "Electrical applications of carbon materials," by D.D.L. Chung.

In recent years, the thermal analysis (TA) technique has been widely applied in aluminum foundries to predict alloy composition and microstructural constituents. This technique has been extended to solidification, providing valuable information for simulation experts, such as characteristic solidification temperatures, the amount of fraction solid, and the alloy feeding ability. This paper analyzes the solidification path of two series of hypoeutectic aluminum alloys, AlSi7Cu(1–4) and AlSi9Cu(1–4), applying differential scanning calorimetry (DSC) and TA techniques. The alloys latent heat (LH) was measured with a DSC apparatus at a cooling rate of 10 °C min−1. The cooling curve was analyzed to calculate the amount of fraction solid and LH released at 10 °C min−1 cooling rate. The Newtonian technique of zero curves was used to establish a baseline and calculate the amount of fraction solid and its LH. The LH calculated by the TA method was compared with the measured values gained by applying DSC and with the calculated LH values obtained by applying the market-available JMatPro software package. The aim of the paper is to show the possibility of determining LH using the TA technique. [ABSTRACT FROM AUTHOR]

This study concentrates on comparing effects of conventional and laser-assisted machining (LAM) of laser-borided Monel 400 alloy. For this purpose, the shaft made from Monel 400 was covered with 200-µm thick boron layer and surface melted using diode laser. For determining the influence of laser beam scanning velocity on final microstructure, microhardness, and depth of melting, four laser beam scanning velocities were set: 5, 6, 8. and 10 m/min. Obtained microstructures are typical for laser-melted metal and are composed of fine crystals. Microhardness increased significantly due to enriching Monel 400 with boron and the level of this increase depends on the laser beam scanning velocity carried out for the process. During both conventional and laser-assisted turning, cutting forces were measured for comparison. Other compared parameters after carrying out these processes were obtained surface roughness and tool life. It was found that it is possible to form laser-borided surface of Monel 400 alloy by machining and using additional laser-assist has a positive impact on the efficiency of the process. Laser-assisted machining allows to lower cutting forces during machining and this leads to extended tool life. On the other hand, this method provides lower values of roughness parameters on the machined surface due to the effect of softening the surface during the process. The paper is the first description of effects obtained by laser-assisted machining of laser-borided surface. [ABSTRACT FROM AUTHOR]

Ti6Al4V alloy is one of the typical difficult-to-machine materials and often results in rapid tool wear, leading to poor machining quality in aircraft assembling. Compared to conventional helical milling, the ultrasonic assistant helical milling (UAHM) process has indicated its superior performance; however, it is still a great challenge to improve the hole surface quality and accuracy. In addition, few studies have been conducted on the effect of different variables and cooling strategies on the hole-making performance in longitudinal-torsional ultrasonic assisted helical milling (LT-UAHM). This paper, for the first time, reports effects of machining variables on geometric precision and surface roughness in LT-UAHM of Ti6Al4V. In addition, the lubrication/cooling mechanism on the simultaneous application of LT-UAHM and MQL is theoretically analyzed. The design approach of Taguchi experiment was employed to study how major variables such as the cutting speed, tangential feed, axial feed, and the workpiece hardness influence the dimensional and geometrical tolerances and surface roughness. This paper also discussed the effect of three cooling strategies, i.e., dry condition, air coolant, and minimum quantity lubrication (MQL) in LT-UAHM. Theoretical analysis demonstrated that the MQL coolant can be nebulized into hyper-fine droplets owing to the resonant cavitation phenomenon. Combined with the penetrating action caused by the separate-cutting principles of LT-UAHM, the cooling and lubrication performance of MQL was further enhanced. As a result, LT-UAHM with MQL had the most positive effect on circularity, cylindricity, nominal diameter, and surface roughness, contributing to 34%, 32%, 39%, and 40%, respectively. The second important machining factor was the cutting speed, contributing to 31%, 29%, 36%, and 22%, respectively. The tangential feed and workpiece hardness have the negative effect on geometrical accuracy, respectively. [ABSTRACT FROM AUTHOR]

Within microservice architecture-based systems, some microservices are integrated to build the software. The integration of these services may be defined based on a workflow model. There are also a variety of different languages available for defining these workflow models. BPMN and YAWL are two such options. It is important that testers test the integration of these microservices. This paper proposes the formal method as the solution for integration testing. This method translates the workflow model to the Alloy. The algorithm has suggested a translation of workflow models to formal specifications. This specification takes into consideration both structural and behavioral aspects. The first perspective is about general structures, while the second is about the behavior of the objects in a specific model. We have proved the correctness of the suggested specifications. For this purpose, the paper has shown that formal definitions are sound and are complete with nine theorems for these properties. The translation from YAWL to Alloy is defined based on their BNF grammar. The generated model is an appropriate source for different purposes containing software testing. The suggested method for software testing is model-driven testing. Logical predicates define the structure of Alloy models. This method uses these logical predicates for generating tests. The test method has used RACC coverage as an example criterion. Alloy Analyzer tests the model by generating test predicates. [ABSTRACT FROM AUTHOR]

Ram Devanathan and Laurent Capolungo are Guest Editors for the ICME Committee of TMS and coordinated the topic on Computational Design of Alloys for Energy Technologies in this issue. The first paper in this topic deals with metal-carbide interfaces that are ubiquitous in alloys and play a crucial role in the mechanical properties. Their work, "Data-guided feature identification for predicting specific heat of multicomponent alloys", shows that it is possible to predict alloy properties reliably even from small datasets if high-quality training data are available. [Extracted from the article]

Background: Mini-screws are widely used as temporary anchorages in orthodontic treatment, but have the disadvantage of showing a high failure rate of about 10%. Therefore, orthodontic mini-screws should have high biocompatibility and retention. Previous studies have demonstrated that the retention of mini-screws can be improved by imparting bioactivity to the surface. The method for imparting bioactivity proposed in this paper is to sequentially perform anodization, periodic pre-calcification, and heat treatments with a Ti–6Al–4V ELI alloy mini-screw. Materials and methods: A TiO2 nanotube-structured layer was formed on the surface of the Ti–6Al–4V ELI alloy mini-screw through anodization in which a voltage of 20 V was applied to a glycerol solution containing 20 wt% H2O and 1.4 wt% NH4F for 60 min. Fine granular calcium phosphate precipitates of HA and octacalcium phosphate were generated as clusters on the surface through the cyclic pre-calcification and heat treatments. The cyclic pre-calcification treatment is a process of immersion in a 0.05 M NaH2PO4 solution and a saturated Ca(OH)2 solution at 90 °C for 1 min each. Results: It was confirmed that the densely structured protrusions were precipitated, and Ca and P concentrations, which bind and concentrate endogenous bone morphogenetic proteins, increased on the surface after simulated body fluid (SBF) immersion test. In addition, the removal torque of the mini-screw fixed into rabbit tibias for 4 weeks was measured to be 8.70 ± 2.60 N cm. Conclusions: A noteworthy point in this paper is that the Ca and P concentrations, which provide a scaffold suitable for endogenous bone formation, further increased over time after SBF immersion of the APH group specimens. The other point is that our mini-screws have a significantly higher removal torque compared to untreated mini-screws. These results represent that the mini-screw proposed in this paper can be used as a mini-screw for orthodontics. [ABSTRACT FROM AUTHOR]

In recent years, more attention to unique and complex structures, such as nature-inspired and porous structures for medical applications, has been strongly developed. Open-cell porous metal-based ones display more benefits than rigid ones since they facilitate the transformation of load between the bone and the implants and avoid the phenomenon of stress shielding and bone resorption. By being biodegradable and non-toxic, as well as having lower density and mechanical properties close to those of natural bone, Mg and its alloys are considered promising materials for porous scaffolds. However, a high corrosion rate is the main drawback of Mg alloys. The porosity of porous structures can also worsen it as it enhances the surface area exposed to the corrosive solution and negatively impacts the performance of porous structures, that these issues have not been addressed in detail so far. Since fabrication methods of Mg-based scaffolds can significantly affect the porosity-related properties (e.g., porosity percentage, type, size, and geometry) and, consequently, scaffolds' mechanical behavior and corrosion resistance, this paper reviews and compares the fabrication methods of porous structures and how they affect the resultant properties. However, among different methods, due to the expansion of additive manufacturing as a novel and exciting manufacturing technique, the paper's central focus is on using additive manufacturing in biomedical applications, discussing its advantages over other techniques. The effect of geometrical parameters on mechanical properties and corrosion rate, which strongly affects bio-application, are also given. Moreover, different strategies are briefly introduced for tailoring the high corrosion rate of Mg and its alloys, such as alloying elements and coatings. However, there is still less information regarding the additive manufacturing of porous Mg scaffolds and the optimum way of controlling the corrosion rate of Mg-based parts. [ABSTRACT FROM AUTHOR]

Si–Ge–Sn alloys are offering unusual material properties with a strong potential to add a variety of functionalities to advanced CMOS technology. Being a group IV alloy, SiGeSn can be monolithically integrated on Si. The discovery of a direct band gap at Sn concentration above 8%, the extremely small effective mass for electrons and holes as well as the pronounced phonon scattering are opening new opportunities for Si photonics, high frequency devices and thermoelectrics. Si–Ge–Sn alloys with Sn concentration far beyond the solid solubility limit are metastable, artificial materials, which request challenging growth conditions. In this paper the epitaxial conditions for Si–Ge–Sn alloys to achieve precise control of the Sn content, to manage the lattice mismatch and defects, as well as to fabricate doped layers are discussed. The applied process control allows for epitaxy of group-IV heterostructures, required for typical devices for photonic and electronic applications. In this context, lasers and nanowires MOSFETs are discussed in this paper. In additions, the thermal conductivity is investigated as a critical material parameter to obtain a high thermoelectric figure of merit in GeSn alloys. [ABSTRACT FROM AUTHOR]

Biodegradable materials like magnesium-based alloys are widely employed for making implants. Mg-based alloys show good biocompatibility, biodegradability, and mechanical properties similar to bone material unlike other commonly used implant materials, i.e., stainless steel, titanium, and Co–Cr alloy, which have negligible degradation rates and require revision surgery for the removal of the implant. Magnesium alloy-based implant has high degradation rates and avoids the need for a second surgery. But high degradation rates and poor mechanical properties in magnesium alloys also pose a challenge to their use as implant material. In the absence of controlled degradation, they can degrade completely before serving their intended purpose in the human body. Several surface modification techniques are used to control the degradation rates. Surface coating is one of the methods of surface modification. This paper discusses various types of surface coating techniques for magnesium-based alloys. This paper also discusses the future scope of surface technology of magnesium-based implant materials. [ABSTRACT FROM AUTHOR]

A list of articles related to physics is presented in the December 2005 issue of the "Journal of Materials Science" including "Adhesively-Bonded Joints and Repairs in Metallic Alloys, Polymers and Composite Materials," by A. Baldan, "Thermo-mechanical fatigue of shape memory alloys," by E. Hornbogen, "Role of Entropy of Fusion in Phase Transformation and Self-Diffusion," by G. P. Tiwari, J. M. Juneja and Y. Ijima, "Models in Thermoluminescence," by C. Furetta and G. Kitis and "Electrical Applications of Carbon Material," by D. D. L. Chung.

In the present research paper, the structural, electronic and thermodynamic properties of the Si1-yCy binary in a super cell consists of 08, 16 and 32 atoms were studied. The Full Potential-Linearized Augmented Plane Wave (FP-LAPW) method was used within the Density Functional Theory (DFT); which was performed directly in WIEN2K code.. The exchange and correlation potential is treated with the local density approximation (LDA). The deviation of lattice parameter was analyzed by the use of Vegard's Law depending on the concentration and, therefore, the results seem to obey the Vegard's law. Moreover, the modified exchange potential proposed by Becke -Johnson to calculate the gap were applied. The results achieved by the local density approximation (LDA) and potential of modified Becke -Johnson (MBJ-LDA) was discussed. Difference in the gap was observed especially in low concentrations y = 0.125; the gap value increases from −0.016 eV to 0.177 eV and when y = 0.5 the gap improved from 1.302 eV to 2.272 eV obtained by the LDA and the MBJ respectively; close to the experimental value 2.39 eV. Next, in order to study the microscopic origin of the bowing gap, Zunger's approach was introduced. Finally, thermodynamic properties were calculated as well as the results were discussed. Based on the results, it can be concluded that the values obtained are in a better agreement with those of other theoretical and experimental data. [ABSTRACT FROM AUTHOR]

Grain-boundary diffusion affects composition profiles developed during selective oxidation in polycrystals. It is therefore desirable to consider the grain size when choosing an alloy or setting acceptable operating conditions for an application where high-temperature corrosion resistance is important. This paper aims to provide guidelines to evaluate subsurface composition changes as a function of grain size and oxidation conditions. We show that depletion profiles around isolated grain boundaries of Ni-based Cr2O3-forming alloys oxidized at 1000 ∘ C can be described by a 2D diffusion model, where fast diffusion at the alloy–scale interface is considered in addition to grain-boundary diffusion. We then illustrate the general features of depletion profiles in polycrystals, in comparison with single crystals. Finally, we use a set of simulations covering a wide range of times, temperatures and grain sizes to identify regimes where a 1D model can be used, either because grain-boundary diffusion can be neglected or because it produces a uniform depletion front. [ABSTRACT FROM AUTHOR]

A novel multi-directional eddy current thermography (ECT) system is presented generating sets of directional phase images that have been fused with a processing pipeline allowing for an improved probability of detection (POD). Inhomogeneous electromagnetic Joule heating derived from the diversion of induced eddy currents provoked by cracks, altering its path around as well as under its bottom, is the principal phenomenon enabling its usage as a non-destructive-evaluation (NDE) technique. Most induction thermography systems employ inductors derived from old designs, optimized for localized heating with a fixed magnetic field direction. This provokes a directional detection blind-spot for surfaces with random crack orientations. In this paper we have observed that the pattern associated with the thermal response distribution can be geometrically correlated to the relative orientation of the magnetic field regarding the crack, conforming to a rotating feature that has not been described before. Extracting the apparent motion as an optical flow, with a phase-shifting interpolation of the intermediate orientations, generates a signal that enables a robust segmentation of a wide variety of defects in ferritic and austenitic alloys. Its performance has been evaluated with two 'Hit/Miss' POD studies TIG welds Inconel 718 and Haynes 282 alloys. Results show an increased detectability regarding the manual labelling of the defects in the same directional set, employing the same input. [ABSTRACT FROM AUTHOR]

Here we use phase field to model and simulate "hopper" crystals, so named because of their underlying cubic structure but with a hopper-like depression on each of the six faces. Over the past three decades simulations of single phase solidification have successfully explored dendritic structures, in two and three dimensions, formed under high undercooling from a slight perturbation in anisotropy. More recently we see the modelling of faceted structures at near equilibrium, and also, under high undercooling, the formation of dendritic-like structures in two dimensions which retain some faceting in the dendrite arms. A cubic hopper crystal appears to be a hybrid structure, somewhere between a perfect cube and a dendrite, and, to date, has not appeared in the modelling literature. In this paper we describe a model for faceted cubic growth and explore results, necessarily in three dimensions, that include perfect cube, hopper and dendritic. We also touch briefly on one other morphology—octahedral. [ABSTRACT FROM AUTHOR]

Topologically close-packed (TCP) phases such as Laves phases are usually considered to harm the mechanical properties of classical superalloys for high-temperature applications. However, if an optimal fraction and size are designed, this situation can completely change for some compositionally complex alloys (CCA). Based on existing studies on austenitic or ferritic steels, we propose in this paper a design strategy aimed at exploiting the role of the Laves phase in defining the mechanical properties of wrought CCAs at elevated temperatures. We demonstrate its efficiency by applying it to the design and production of a new Laves phase—reinforced CCA and present the results of their experimental and theoretical investigation. The results show that a new Laves phase-reinforced CCA can have fine-grained microstructures, lower density, and superior mechanical strength at elevated temperatures while maintaining workability. These new alloys show promising properties compared to existing CCA wrought alloys and actual Ni-based superalloys. [ABSTRACT FROM AUTHOR]

Processability refers to the ease of achieving the required component while maintaining mechanical performance and processing schedules, which are critical for determining the cost and efficiency of using a given material, from the raw condition to the final product of any manufacturing process. Components built using the laser powder bed fusion with metallic alloys (LPBF-M) process show variability in their mechanical performance, which can be attributed to a range of process parameters and characteristics of the powder material employed by each type of machine. These variations are currently hindering the adoption of this technology at the industrial level. This paper presents a processability approach that could be applied in the LPBF-M to evaluate the possibility of speeding up productivity and minimising the effect on the mechanical properties and relative density and is defined based on the process parameters and powder material characteristics that generate the melting pool and meet bonding criteria at a specific build rate. A case study is carried out with stainless steel 316 (SS316), although this processability analysis could be applied to any other alloy. The results show that a wide range of process parameters generates a suitable processability interval with different values of the build rate. It is also found that slow build rates give rise to less variability in the mechanical properties, while faster rates produce more variability; this is caused by a fast-growing melt pool due to the use of high scan velocities for the SS316 alloy under study. [ABSTRACT FROM AUTHOR]

The cracking of nickel-based single-crystal alloys is associated with the residual stress. In this paper, we employed focused ion beam and digital image correlation (FIB-DIC) technology to characterize the crack-tip residual stress at ultrahigh spatial resolution. The repeatability and accuracy of FIB-DIC were validated by experiments and simulations. A direct correlation between residual stress and hardness was established, which provides a new way to prevent cracking through the visualization and control of residual stress. [ABSTRACT FROM AUTHOR]

Benjamin Adam is the Guest Editor for the TMS High Temperature Alloys Committee and organized the topic High Temperature Alloys: Manufacturing, Processing, and Repair in the August and September 2022 issues of JOM. This I JOM i topic is sponsored by the High-Temperature Alloys Committee of TMS and addresses advances in the manufacturing and processing of high-temperature alloys. Finally, in 2022, a symposium will be organized for the Materials Science and Technology Conference in Pittsburgh, PA on October 9-13: "Alloy Phase transformations at elevated temperature alloys". [Extracted from the article]

The mechanical properties possessed by surface layers of metal alloys hardened by severe plastic deformation methods were studied by indentation. The test materials were AISI O2 and AISI 316L steels and D16 aluminum alloy. Most scientific papers evaluate the mechanical properties of hardened surface layers and thin coatings only by hardness measurement. Hardness alone cannot characterize the ductility of a material without using modern concepts for determining the physical ductility from hardness. The mechanical behavior of a material can only be characterized by determining both the ductility and the yield stress. These quantities can be found by micro- or nanoindentation. We developed indentation methods to find the physical ductility δH and yield stress σSH of the surface layers of metal alloys hardened by various techniques (with analysis of changes in these characteristics across the hardened layer) to select the optimal hardening method. The hardening characterized by the ratio between the yield stresses of the hardened layer and the starting material σ SH hard / σ SH start was much greater for all studied alloys than the hardening characterized by the hardness ratio (HVhard/HVstart). Thus, the use of δH and σSH obtained from standard microhardness measurements enhanced the informative nature and efficiency of the indentation method in studying the mechanical behavior of metal alloy layers hardened by various techniques. [ABSTRACT FROM AUTHOR]

In this paper, we draw attention to the investigation of the novel exact solution [1.Scripta Mat. 210:114430; M.A. Dayananda, in JPED, this issue, (2022);] that is applicable to a multicomponent (n-component) interdiffusion couple where the interdiffusion matrix may change with alloy composition. In the derivation of this solution the interdiffusion flux J j of a component j is related to (n-1) independent composition gradients for an isothermal, diffusion couple using the well-known continuity equation. Novel exact expressions are then derived for all of the interdiffusion coefficients, D ~ ij n (i, j = 1, 2, .....n − 1), where the partial derivatives of the product J j y - y 0 with respect to composition C i ( y 0 is the Matano plane) are used. In this paper, it is shown that the novel solution leads to a computational procedure similar to the Boltzmann-Matano analysis. Note that the derivatives ∂ (J j y - y 0 ) / ∂ C i , i , j = 1 , ... , n - 1 (that are required for the solution) can only be calculated along the diffusion path and therefore, for n > 2 , a single couple will not be enough to calculate all of them correctly. [ABSTRACT FROM AUTHOR]

A cross-scale analysis method for predicting the compressive mechanical properties of tin-based bearing alloy was proposed based on microstructure finite element simulation and molecular dynamics (MD) simulation. The actual metallographic microstructure of tin-based bearing alloy taken by optical microscopy was utilized to construct the representative volume element (RVE) model for the computational modeling. The compression stress–strain curves of β-Sn and Cu6Sn5 obtained by MD simulation were used as the input material property parameters of each constituent phase in RVE model for the microstructure finite element analysis. The compression simulation was carried out for the tin-based bearing alloy with the microstructure containing Sn matrix and Cu6Sn5 phase. The results show that the simulation analysis method can predict the compression strength and elasticity of the studied tin-based bearing alloy well by comparing the simulated results with the experimentally obtained data. It is hoped that this paper can provide a simulation method for realizing the prediction of the mechanical properties based on microstructure and revealing the microscope mechanism of materials, thus providing theoretical guidance for the micro-design of high-performance tin-based bearing alloy. [ABSTRACT FROM AUTHOR]

Although rare-earth magnesium (Mg-RE) alloys are widely used in various industries, they show much poorer machinability for shaping into desired dimensions than conventional magnesium ones. The most critical issues associated with cutting Mg-RE alloys are high risk of chip ignition and short tool life dominating the chip removal process. The present paper aims to address the tool performances on the machinability of Mg-RE alloys under dry cutting. Four types of tools covering uncoated and diamond-coated ones were examined, and a special focus was devoted to explore the effects of various tool parameters on the milling responses of Mg-RE alloys as well as the underlying wear mechanisms. The experiments reveal that the cutting tools with larger rake, clearance, and helix angles can achieve high-quality milling of Mg-RE alloys at controllable cutting temperatures. The cutting parameters can be maintained at a certain level, such as the cutting speed of 120–240 m/min and the feed per tooth of 0.1–0.2 mm/z, to meet the requirements of safe milling of Mg-RE alloys without ignition risk. [ABSTRACT FROM AUTHOR]

The unclear contraction behavior of Mg-Gd-Y-Zr alloy during low-pressure sand casting bring obstructs into the dimensional control in the fabrication of large and complex parts, restricting the further engineering applications of this alloy. This paper investigated the rule for free and constrained contraction of typical Mg-Gd-Y-Zr (Mg-9Gd-3Y-0.5Zr, VW93K) alloy during low-pressure sand casting. A series of castings with different volumes and geometric structures were designed and a 3D scanner was employed to measure different types of dimensions, which were then used for the calculation of contraction coefficients. The convergent value of free contraction coefficients was derived through statistical analysis, and the correlation between constrained contraction coefficients and geometric characteristics of castings was established by the utilizing of core volume factor. In the condition of low-pressure casting, free contraction coefficients of VW93 alloy are concentrated around a fixed value of 1.72%, constrained contraction coefficients of VW93 alloy show a decreasing linear tendency against core volume factor, and pouring pressure makes effects on free contraction. The experimental results and proposed formulas provide guidance for accurate dimensional control in fabrication of large and complex Mg-RE alloy parts by low-pressure sand casting. [ABSTRACT FROM AUTHOR]

Grain size has a significant impact on the superelasticity of alloys. Large-sized grains show superior superelastic properties because the grain boundaries are minimized and the grain constraints caused by triple junctions are reduced. Cyclic heat treatment (CHT) is commonly employed to generate subgrains, whose energy can be consumed to induce abnormal grain growth (AGG) and obtain large-sized grains. In this paper, the effects of adding Cu on the subgrain characteristics during AGG and microstructural evolution of FeMnAlNi-based superelastic alloys were systematically investigated. The addition of Cu reduced the temperature at which the γ phase precipitates and altered the morphology of the γ phase. After the dissolution of the refined γ phases, the average subgrain size became smaller and misorientation increased. These characteristic subgrain changes improved the driving force for AGG and accelerated the grain boundary migration rate. Due to the addition of Cu, the maximum grain size reached 28.2 mm. This study provides a new method for the preparation of FeMnAlNi-based superelastic alloys with large-sized grains. [ABSTRACT FROM AUTHOR]

Porous Zn scaffold, as a novel biodegradable metallic material, has emerged as a promising candidate for biomedical applications. In this paper, by using carbamide particles as the pore-making agent and Zn and Mg powders as the starting materials, porous Zn-Mg alloy scaffolds were fabricated via the low-temperature sintering route. A so-called one-step hydrothermal method was applied to form a hydrophobic film on surface of the porous Zn alloy scaffolds. The degradability of the porous Zn alloy scaffolds coated with/without hydrophobic film in the simulated body fluid (SBF) was investigated, and the results show that the hydrophobic film, which can adhere well to the metal substrate with thickness around 50 μm, can effectively delay the degradation of porous Zn alloy scaffolds; the degradation rates of porous Zn alloy scaffolds coated by the hydrophobic film are 26–57% lower than those of porous scaffolds without coating; especially the degradation rate of the porous Zn-5 wt.%Mg scaffold with the coating in SBF, which is 0.32 mg/(cm2 day), is at the same level as that of pure Zn. [ABSTRACT FROM AUTHOR]

Ductility dip cracking (DDC) is a solid-state failure occurring during multi-pass solidification processes (e.g., welding, additive manufacturing) for FCC alloys that exhibit a distinct dip in their ductility at intermediate temperatures. While the phenomenon has been studied for over a century, the majority of current research focuses on a subset of DDC-susceptible FCC alloys (Ni–Cr–Fe). The review paper herein presents an analysis of published data to evaluate the current state of understanding regarding the materials mechanisms at work. Recent advances in test methods have permitted highly controlled approaches for testing and quantifying DDC, but the wide range of unique tests often provide conflicting results regarding the fundamental materials behaviors and underlying mechanisms. At present, three mechanisms have been proposed for DDC: grain boundary sliding, precipitate-induced strain, and impurity element segregation. While the majority of published studies support grain boundary sliding as the primary mechanism of DDC, an examination of the aggregate data available across multiple studies suggests combinatorial impact of simultaneous (and competing) mechanisms for DDC. Further, the long-held assumptions regarding the negative impact of key alloying elements become less convincing when comparing results across studies. There are considerable future opportunities for research on DDC behaviors in other alloy systems, and there are a lacunae of data when considering the effect of welding process parameters on DDC and the use of modeling and simulation approaches to understand the DDC behavior in the highly susceptible FCC alloy systems. [ABSTRACT FROM AUTHOR]