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Lightweight design strategies and advanced energy applications call for high-strength Al alloys that can serve in the 300‒400 °C temperature range. However, the present commercial high-strength Al alloys are limited to low-temperature applications of less than ~150 °C, because it is challenging to achieve coherent nanoprecipitates with both high thermal stability (preferentially associated with slow-diffusing solutes) and large volume fraction (mostly derived from high-solubility and fast-diffusing solutes). Here we demonstrate an interstitial solute stabilizing strategy to produce high-density, highly stable coherent nanoprecipitates (termed the V phase) in Sc-added Al–Cu–Mg–Ag alloys, enabling the Al alloys to reach an unprecedented creep resistance as well as exceptional tensile strength (~100 MPa) at 400 °C. The formation of the V phase, assembling slow-diffusing Sc and fast-diffusing Cu atoms, is triggered by coherent ledge-aided in situ phase transformation, with diffusion-dominated Sc uptake and self-organization into the interstitial ordering of early-precipitated Ω phase. We envisage that the ledge-mediated interaction between slow- and fast-diffusing atoms may pave the way for the stabilization of coherent nanoprecipitates towards advanced 400 °C-level light alloys, which could be readily adapted to large-scale industrial production.High-density, highly stable coherent nanoprecipitates are created in Al alloys that enable high strength and creep resistance at 400 °C. This is realized via a growth-ledge-triggered in situ phase transformation assembling slow-diffusing solutes with high-solubility solutes into nanoprecipitates.

Wear-related energy and material loss cost over 2500 Billion Euro per year. Traditional wisdom suggests that high-strength materials reveal low wear rates, yet, their plastic deformation mechanisms also influence their wear performance. High strength and homogeneous deformation behavior, which allow accommodating plastic strain without cracking or localized brittle fracture, are crucial for developing wear-resistant metals. Here, we present an approach to achieve superior wear resistance via in-situ formation of a strong and deformable oxide nanocomposite surface during wear, by reaction of the metal surface with its oxidative environment, a principle that we refer to as ‘reactive wear protection’. We design a TiNbZr-Ag alloy that forms an amorphous-crystalline oxidic nanocomposite surface layer upon dry sliding. The strong (2.4 GPa yield strength) and deformable (homogeneous deformation to 20% strain) nanocomposite surface reduces the wear rate of the TiNbZr-Ag alloy by an order of magnitude. The reactive wear protection strategy offers a pathway for designing ultra-wear resistant alloys, where otherwise brittle oxides are turned to be strong and deformable for improving wear resistance. Wear-resistant metals have long been a pursuit of reducing wear-related energy and material loss. Here the authors present the ‘reactive wear protection’ strategy via friction-induced in situ formation of strong and deformable oxide nanocomposites on a surface.

Alloying is a powerful tool that can improve the electrocatalytic performance and viability of diverse electrochemical renewable energy technologies. Herein, we enhance the activity of Pd-based electrocatalysts via Ag-Pd alloying while simultaneously lowering precious metal content in a broad-range compositional study focusing on highly comparable Ag-Pd thin films synthesized systematically via electron-beam physical vapor co-deposition. Cyclic voltammetry in 0.1 M KOH shows enhancements across a wide range of alloys; even slight alloying with Ag (e.g. Ag 0.1 Pd 0.9 ) leads to intrinsic activity enhancements up to 5-fold at 0.9 V vs. RHE compared to pure Pd. Based on density functional theory and x-ray absorption, we hypothesize that these enhancements arise mainly from ligand effects that optimize adsorbate–metal binding energies with enhanced Ag-Pd hybridization. This work shows the versatility of coupled experimental-theoretical methods in designing materials with specific and tunable properties and aids the development of highly active electrocatalysts with decreased precious-metal content. Electrocatalyst development is key to improving the performance and viability of many electrochemical energy technologies. Here, the authors design Ag-Pd alloys with specifically tuned electronic structures to have enhanced oxygen reduction electrocatalysis and decreased precious metal content.

Scandium added to Al–Cu–Mg–Ag alloys leads to an in situ phase transformation of coherent Cu-rich nanoprecipitates at elevated temperature, with Sc atoms diffusing and occupying their interstitial sites. The transformed nanoprecipitates have enhanced thermal stability while maintaining a large volume fraction and these two microstructural features enable high tensile strength of the Al alloy with creep resistance up to 400 °C.

Al-Cu-Mg-Ag alloys are widely used in aerospace due to their excellent heat resistance, high specific strength, and good machinability. In solidification, the compositional distribution and segregation of the alloy play an important role in its properties. Therefore, in this paper, the solidification phase field model was established by using the phase field method to simulate the compositional distribution of the alloy after solidification. The experiments show that the solutes are expelled during the advancement of the interface to the liquid phase, and that the content of each element is higher in the intergranular than in the intragranular, with the most severe enrichment of Cu, which exists in the form of θ-phase, and a lesser enrichment of Si, with respect to the Mg and Ag elements. The experimental results are in full agreement with the pattern predicted by simulations.

As a typical structural material with high strength, lightweight, heat resistance, and good processability, Al-Cu-Mg-Ag alloy has been widely used in aerospace, automobile manufacturing, electronic equipment, and other fields. However, in the actual service environment, Al-Cu-Mg-Ag alloy still has failure or damage. In this regard, based on the actual application requirements, this paper will deeply study the influence of the surface ultrasonic rolling process on the microstructure and properties of Al-Cu-Mg-Ag alloy, and analyze and verify it through design experiments. The practice has proved that there is no new phase before and after ultrasonic rolling. When the load is 0.3 MPa and the reduction is 0.1 mm, the surface thickness of the alloy reaches 70μm and the surface hardness is increased by 49.%. In addition, the electrochemical test results show that the corrosion resistance of alloy samples treated by the surface ultrasonic rolling process is obviously enhanced, which is 2.43 times higher than that of untreated samples.

The methodological advancements in surface‐enhanced Raman scattering (SERS) technique with nanoscale materials based on noble metals, Au, Ag, and their bimetallic alloy Au–Ag, has enabled the highly efficient sensing of chemical and biological molecules at very low concentration values. By employing the innovative various type of Au, Ag nanoparticles and especially, high efficiency Au@Ag alloy nanomaterials as substrate in SERS based biosensors have revolutionized the detection of biological components including; proteins, antigens antibodies complex, circulating tumor cells, DNA, and RNA (miRNA), etc. This review is about SERS‐based Au/Ag bimetallic biosensors and their Raman enhanced activity by focusing on different factors related to them. The emphasis of this research is to describe the recent developments in this field and conceptual advancements behind them. Furthermore, in this article we apex the understanding of impact by variation in basic features like effects of size, shape varying lengths, thickness of core–shell and their influence of large‐scale magnitude and morphology. Moreover, the detailed information about recent biological applications based on these core–shell noble metals, importantly detection of receptor binding domain (RBD) protein of COVID‐19 is provided. Bimetallic alloy Au–Ag surface‐enhanced Raman scattering (SERS) biosensors exhibit ultrahigh SERS sensitivity. Au–Ag SERS‐based biosensors have been utilized in biological components detection, including; proteins, antigens antibodies complex, circulating tumor cells, DNA, and RNA (miRNA), etc.

Al-Cu-Mg-Ag alloys are widely used in aerospace field due to their excellent heat resistance, high specific strength and good machinability. In order to obtain excellent performance, the control of its solidification structure is very important, so it is necessary to numerically simulate its solidification structure and then control its structure. In this paper, the solidification phase field model was established by phase field method to study the microstructure evolution during solidification. The solidification process of Al-Cu-Mg-Ag-Si alloy is simulated and verified by experiments. The results show that the grains grow in cellshape and the second phase forms at the grain boundary of α phase. The faster the cooling rate, the smaller the grain size and the lower the content of the second phase. The samples were observed by metallography and scanning electron microscopy, and the phase composition of the as-cast samples was characterized by EDS and XRD. It is verified that the second phase in simulation and experiment is mainly θ phase, and the grain morphology accors with th simulation results.

Ag-Sn-In-Ni-Te alloy ingots were produced through a heating–cooling combined mold continuous casting technique; they were then drawn into wires. However, during the drawing process, the alloy wires tended to harden, making further diameter reduction challenging. To overcome this, heat treatment was necessary to soften the previously drawn wires. The study investigated how variations in heat treatment temperature and holding time affected the microstructure, microhardness and corrosion resistance of the alloy wires. The results indicate that the alloy wires subjected to heat treatment at 700 °C for 2 h not only exhibited a uniform microstructure distribution, but also demonstrated low microhardness and excellent corrosion resistance.

This article introduces the addition of Mg, Ag trace elements, and AlTi5B refiners to the Al-Cu-Mn alloy furnace charge to regulate the size, morphology, and distribution of precipitates, as well as the distribution of particles, to form highly dispersed and thermally stable nanoparticles. A high strength and toughness Al-Cu-Mn-Mg-Ag alloy with fine microstructure and uniform grain distribution is obtained. The experimental results indicate that the addition of Mg, Ag trace elements, and AlTi5B in Al-Cu-Mn alloy can significantly refine α- Al dendrite, the grain size can be refined to 150 μ below m, and the microstructure is more uniform. When the Mg content is 0.2% and Ag content is 0.3%, the T (Al 20 Cu 2 Mn 3 ) phase at the grain boundary is significantly increased, and the T phase is in a point-like and discontinuous distribution at the grain boundary. At this time, the comprehensive performance of the alloy is the best (Rm: 431 MPa; RP0.2: 251 MPa; A: 13.2%; hot crack ring width: 20 mm).