An ultrafine lamellar structure with tailored phase fractions was developed in a martensitic stainless steel via heavy warm rolling followed by quenching and partitioning (Q&P) treatment, leading to a superior strength-ductility synergy. Heavy warm rolling established an ultrafine lamellar martensitic matrix with a high dislocation density, while subsequent Q&P treatment tailored the fractions of tempered martensite (TM), retained austenite (RA), and fresh martensite (FM). As the quenching condition was varied, the retained-austenite fraction first increased and then decreased, while fresh martensite formation was inferred at higher quenching temperatures, and its estimated contribution increased thereafter. Tensile strengths of 1986–2554 MPa and uniform elongations of 3.1–10.5% were achieved, with the optimum strength-ductility balance obtained in the condition characterized by a high retained-austenite fraction and a limited estimated contribution of fresh martensite. The superior ductility is associated with the gradual transformation of retained austenite over a wide strain range, which enabled sustained transformation-induced plasticity and persistent strain hardening, whereas the increasing estimated contribution of fresh martensite enhanced strength but reduced uniform elongation. A semi-quantitative phase-dependent strengthening analysis further rationalized the yield strength evolution. Overall, the superior strength-ductility synergy originates from the coupling of an ultrafine lamellar martensitic matrix and tailored phase fractions.

Building on conventional cyclic heat treatment (CHT), this study introduces a multiple rapid-heating (MRH) strategy tailored for low-carbon low-alloy (LCLA) steels, enabling efficient grain refinement through coordinated carbide dissolution and austenitization. The MRH process achieves complete austenitization within seconds and refines the prior austenite grain size to similar to 2.9 mu m and the effective grain size to similar to 1.8 mu m. This refined microstructure achieves a yield strength over 1.5 GPa and an ultimate tensile strength above 2.0 GPa with retained ductility. The ultrafast heating rate and zero-holding strategy are the key to this refinement, which enable an extremely high nucleation rate for austenite while intrinsically limiting grain growth. Employing a hot-rolled state with epsilon-carbides, rather than an annealed pearlitic microstructure, allows complete carbide dissolution during rapid heating, thereby shortening the required austenitization times. The (Nb,Ti)(C,N) precipitates introduced by microalloying remain stable throughout the process, providing a persistent Zener pinning effect. Quantitative strengthening analysis indicates that the superior strength-ductility synergy arises from the combined effects of grain boundary strengthening and dislocation strengthening. This work establishes a cost-effective pathway to achieve ultrahigh strength in LCLA steels by overcoming the intrinsic incompatibility between carbide dissolution and short austenitization time.

The H2S corrosion mechanism of Cu foil current collectors under simulated non-operating exposure conditions relevant to sulfide solid-state batteries has been systematically investigated from a crystallographic perspective. The corrosion product is precisely identified as a single-layer monoclinic Cu2S phase. This study reveals, in the context of solid-state batteries, the mesoscale spatial corrosion sequence, the three-dimensional structure of the corrosion scale and its growth texture, as well as the nanoscale microstructural characteristics of the internal corrosion region. The poor H2S corrosion resistance of pure copper is attributed to the intrinsically Cu-vacancyrich crystal structure of the corrosion product and its poor growth compatibility with the Cu matrix.

Here, Guinier-Preston (GP) zones were, for the first time, induced in a Cu-Al alloy through Zr microalloying combined with heavy warm rolling and short-time annealing. Benefiting from the synergy of high-density annealing nanotwins, GP zones, and their interactions with stacking faults (SFs), the alloy achieved an exceptional strength-ductility balance, with a yield strength of 950 MPa and an elongation above 10 %, comparable to or even surpassing conventional high-strength copper alloys. The GP zone-SF interaction promotes stress homogenization by preventing dislocation pile-up at grain or phase boundaries, while also sustaining strain hardening during later stages of deformation.

Elemental redistribution, particularly the solute exchange between the matrix and precipitates, is a central issue in alloys subjected to severe plastic deformation (SPD). To elucidate this behavior, a nickel-aluminum bronze (NAB) alloy was processed by high-pressure torsion (HPT), and its microstructural evolution was systematically investigated using multiscale characterization techniques. A dynamic competition between precipitate dissolution and reprecipitation was identified during SPD. More notably, direct evidence was provided for the diffusion of the matrix element Cu into kappa precipitates under heavy deformation, leading to the formation of high-density Cu-rich AlCu3 nanoparticles embedded within the kappa precipitate. This unusual elemental redistribution was shown to be thermodynamically favorable under the nonequilibrium conditions induced by SPD. By extending a classical size concentration model based on Fick's second law to a multicomponent alloy system, the coupled growth behavior of AlCu3 nanoparticles and the kappa precipitate is successfully rationalized. These results provide new insight into elemental diffusion pathways and microstructural evolution in complex alloys subjected to SPD. (sic)(sic)(sic)(sic)(sic)(sic)(Severe Plastic Deformation, SPD)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(Nickel-Aluminum Bronze, NAB)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(High-Pressure Torsion, HPT)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic),(sic)SPD(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic),(sic)kappa(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Cu(sic)AlCu3(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Cu(sic)kappa(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)SPD(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)Fick(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)-(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)AlCu3(sic)(sic)(sic)(sic)(sic)kappa(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)SPD(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

It is essential to develop efficient non-precious metal catalysts for urea oxidation reactions (UOR) to enable hydrogen production. In this work, the NiS/Cu2S heterostructure was obtained via a simple surface sulfidation treatment of Monel 400 alloy to investigate electrochemical reconstruction behavior under UOR conditions. The results showed that the selective dissolution and redeposition of alloy elements in NiS/Cu2S induced phase reconstruction, suggesting the formation of CuS/Ni(OH)(2)/NiOOH heterostructure. Although the precursor undergoes phase transition after chronopotentiometric aging (CP-aging), the reconstructed structure shows an outstanding electrocatalytic UOR performance, which requires a low potential of 1.362 V (RHE) to achieve the current density of 10 mA cm(-2). The ex-situ characterization indicates changes in surface element valence and phase, which provides a new strategy for designing high performance electrocatalysts by surface engineering.

Micro-textured regions (MTRs), which are formed by thermomechanical processing of titanium alloys with α + β lamellar structure, induce incompatible deformation and result in early crack initiation during plastic deformation. In this study, we developed an innovative thermomechanical processing routine that eliminates the formation of band-like MTRs in Ti-6Al-4V alloy. The first step of this routine is solution treatment at 1050 °C for 20 min followed by ice water quenching, to obtain an initial microstructure of full acicular α’ martensite. As a comparison, a sample with typical α + β lamellar structure was fabricated by solution treatment at 1050 °C for 20 min followed furnace cooling. Thereafter, both the two samples were processed with a heavy warm rolling procedure at 700 °C and an annealing treatment at 700 °C for one hours. Microstructure characterization showed that after heavy warm rolling and subsequent annealing at 700 °C, acicular α’ martensitic transform into homogeneous and random fine equiaxed grains. This is in contrast with the annealed α + β lamellar structure that a large number of band-like MTRs are formed. Mechanical properties of the sample with annealed martensite are thus significantly improved due to the elimination of MTRs. The strength reaches 1100 MPa, and the total elongation is approximately 14.3

With the rapid development of the titanium alloy industry, low-cost titanium alloys have garnered increasing attention. In this study, a typical low-cost Ti-4Al-2.5V-1.5Fe alloy was selected as experimental material. The alloy was subjected to heavy warm rolling at the alpha+ (3 phase region, followed by annealing treatments at 600 degrees C, 700 degrees C, 800 degrees C, 850 degrees C, and 900 degrees C for 1 h, respectively. Thermodynamic calculations revealed that heavy warm rolling introduced a high density of dislocations within alpha phase, increasing its free energy and lowering the phase transformation temperature. During subsequent annealing, particularly at 800 degrees C, a large number of finely dispersed nano-sized (3 particles precipitates from the alpha phase matrix, simultaneously improve the strength and ductility. These nano-(3 phases contributed to a sustained work hardening during tensile deformation, thereby imparting excellent strength-ductility synergy to the low-cost Ti-4Al-2.5V-1.5Fe alloy. The findings of this study offer a novel strategy for simultaneous strengthening and toughening in other alpha+(3 titanium alloys.

Copper and its alloys are widely used in aerospace, electronics, energy, and advanced manufacturing because of their excellent electrical and thermal conductivity combined with favorable mechanical properties. However, when exposed to elevated temperatures, these materials are highly susceptible to oxidation, which degrades surface integrity, reduces service reliability, and limits their application in demanding environments. Although substantial progress has been made in recent decades, a systematic and up-to-date review dedicated to the high-temperature oxidation of copper alloys remains lacking. This review summarizes the oxidation behavior of pure Cu and representative Cu-based alloy systems, including Cu–Al, Cu–Ni, Cu–Cr, Cu–Zn, Cu–Be, Cu–Sn, and Cu–Si alloys, with emphasis on oxidation kinetics, oxide-scale structures, and the roles of temperature, oxygen partial pressure, composition, and microstructure. The review further discusses major protection strategies, including alloying design, coating technologies, annealing-induced pre-oxidation, and microstructural regulation. Recent mechanistic advances are also highlighted, such as cross-scale oxide growth, surface homogenization induced by elemental diffusion and consumption, and the construction of atomic-scale protective scales. By integrating classical oxidation theory with recent experimental progress, this review clarifies the governing factors for oxidation resistance in Cu-based alloys and provides perspectives for the design of next-generation copper alloys capable of service under increasingly severe high-temperature conditions.

To accurately predict and evaluate the creep characteristics of nickel-based alloys, it is essential to systematically consider the relationship between tensile properties and creep properties. This article investigates the high-temperature performance of a nickel-based alloy under different temperatures and stresses. The primary contribution of this work is the proposal of a novel normalization methodology that integrates tensile parameters into established creep models. The Wilshire equation was used to analyze the minimum creep rate and life of various alloys. Based on the strain rate and elongation from tensile tests, the Monkman–Grant relationship and Wilshire equation were modified. The results indicate a close relationship between creep strength and tensile strength. The Wilshire equation effectively describes creep data over a wide range of lifetimes, and the modified Monkman–Grant relationship and Wilshire equation better characterize creep performance, providing a unified framework for creep life prediction.

An ultra-strong steel with enhanced ductility and ultrafine lamellar structure was produced by heavy warm rolling (HWR) of metastable austenite and subsequent quenching. The HWR steel exhibited an ultrahigh yield strength of 1.09 GPa and an ultimate tensile strength of 2.6 GPa, with a total elongation of 6.7

A heavy warm rolling followed by tempering and partitioning (HWRTP) process was employed to develop a martensitic stainless steel with ultrahigh strength and good ductility. The results show that the heavy warm rolling process significantly reduces the prior austenite grain size (PAGS) compared to the direct quenching (DQ) process. The microstructure after heavy warm rolling is characterized by ultrafine lamellar structured martensite with retained austenite. Heavy warm rolling followed by tempering and partitioning (T P) treatment at 300 °C for 2.0 h achieves an excellent strength–ductility balance: a yield strength of 1647 MPa, an ultimate tensile strength of 2141 MPa, and a total elongation of 13

The rapid expansion of titanium alloy industry has driven a strong focus on low-cost design and development. To meet this demand, the Ti-4Al-2.5V-1.5Fe alloy has been developed as a promising alternative to traditional Ti-6Al-4V alloy. However, researches on the strengthening and toughening this new alloy remain limited. In this study, both Ti-6Al-4V and Ti-4Al-2.5V-1.5Fe alloys underwent heavy warm rolling followed by water cooling (WC), then, were subsequently annealed at 600 °C, 700 °C, and 800 °C for 1 h. During the annealing process, the partition of alloying elements (Al, V, Fe) between the α and β phases resulted in changes in volume fraction, microhardness, and grain size, which in turn, led to significant variations in the mechanical properties of the alloys at different annealing temperatures. The results demonstrate that the optimal mechanical properties for both alloys were achieved at an annealing temperature of 700 °C. Moreover, Ti-4Al-2.5V-1.5Fe alloy exhibited mechanical properties superior to conventional Ti-6Al-4V alloy. The enhanced strength of Ti-4Al-2.5V-1.5Fe is attributed to a higher β-phase content, which contributes to substantial second-phase strengthening. Furthermore, the improved plasticity of Ti-4Al-2.5V-1.5Fe compared to Ti-6Al-4V is largely due to more pronounced twinning deformation, significantly enhancing the alloy’s ability to accommodate deformation.

Understanding the strengthening mechanism of high entropy alloys (HEA) is vital to improve their mechanical properties. In this study, we thoroughly investigated the strengthening effect of L12 nanoprecipitates on the mechanical properties of the face-centered cubic (FCC) CoCrFeNi HEA. The L12 nanoprecipitates were introduced by adding titanium (Ti), niobium (Nb), and aluminum (Al). Following a series of heat treatments (aged at 400 degrees C, 600 degrees C, and 800 degrees C for 4 h), the samples aged at 800 degrees C exhibited a noticeable improvement in tensile strength compared to the CoCrFeNi-based alloy, while maintaining excellent ductility (elongation greater than 29 %). This enhanced in performance is primarily attributed to the synergistic effects of multiple strengthening mechanisms, with precipitation strengthening playing a particularly prominent role (Delta sigma P = 385.6MPa). Transmission electron microscopy (TEM) results revealed that the volume fraction of L12 precipitates reached 35 %, with sizes around 12 nm. This study provides valuable theoretical insights for optimizing the composition and processing strategies of high entropy alloys and lays a solid foundation for the development of high-performance alloys suited to complex engineering applications.

Here, we present a novel microstructural design for a Co-free Ni42Fe30Cr12Mn8Al5Ti3 complex-concentrated alloy (CCA), where partial recrystallization and nanoprecipitation are synergistically integrated via a simple thermomechanical process. This partially recrystallized heterogeneous structure give rise to a high yield strength of similar to 1.2 GPa, an ultimate strength of similar to 1.4 GPa and a tensile elongation of 21.2 % at room temperature. The tensile elongation of the partially recrystallized sample is almost five times higher than that of the cold-rolled sample while without sacrificing strength. The obtained outstanding mechanical properties in the partially recrystallized microstructure have been discussed based on hardening effects due to dislocations, grain refinement, nanoprecipitates and heterogeneous deformation between the non-recrystallized coarse grains and recrystallized fine grains. It may provide important insight for the future development of high-performance cost-effective CCAs via microstructural tailoring.

In this study, we investigated the microstructure evolution and mechanical properties of heavy cold-rolled Custom 465 maraging stainless steel subjected to annealing treatments at various temperatures ranging from 300 to 1000 degrees C. The results indicate that the evolution of microstructure and mechanical behavior can be distinctly divided into three stages as the annealing temperature increases. In the aging stage (Stage A), when annealing temperature is below 550 degrees C, the synergistic effects of ultrafine lamella structure, high-density dislocations, and newly formed fl-Ni3Ti precipitates contributed to the exceptional mechanical properties, demonstrating ultrahigh yield strength of 2011 MPa, ultimate tensile strength of 2034 MPa, and low uniform elongation of 0.42 % when annealed at 500 degrees C. In the overaging stage (Stage B), when annealing temperature is within the range of 600-700 degrees C, the primary microstructural changes observed are the formation of reverted austenite and the coarsening of the fl-Ni3Ti precipitates, which exhibits low work hardening capacity and good elongation. In the recrystallization stage (Stage C), annealing above 750 degrees C allows for complete austenitization during the holding period, and the formation of fresh martensite. Annealing at 750 degrees C results in the austenite content of 84 vol%, with the average prior austenite grain size of 1.04 mu m, whereas annealing temperature is above 850 degrees C, the increased prior austenite grain size leads to the formation of fresh martensite and results in mechanical properties similar to those of the undeformed Custom 465. In addition, in the heavy cold-rolled Custom 465, the precipitation phase transitions from fl-Ni3Ti to Laves phase with increasing annealing temperature, with the transformation occurring at 700 degrees C. Moreover, the ultrafine refinement of prior austenite grain size effectively enhances the stability of austenite. These observations provide valuable insights into the microstructural design and control of ultrahigh-strength steels.

The impact of rolling temperature and the crystallographic orientation of alpha-colonies on the globularization behavior of lamellar alpha+/7 microstructure in Ti-6Al-4V alloy was investigated. Firstly, the lamellar structure was heavily rolled at 600, 700, 800 and 900 degrees C, respectively. Heavy rolling from temperatures of 600 to 900 degrees C resulted in an increased volume fraction and thickness of /7 lamellae, while the corresponding parameters for alpha lamellae decreased. Then, these rolled alpha+/7 lamellar microstructures were spheroidized into equiaxed grains upon subsequent annealing. The results demonstrate that the globularization fraction of the lamellar structures diminishes as the rolling temperature increases. Additionally, the globularization fraction for alpha-colonies with hard crystallographic orientations, such as (0001 //ND and (0001 //TD, is considerably lower compared to those with softer orientations, positioned at certain angles to ND, RD, and TD during annealing process. This results in heterogeneous globularization of alpha lamellae, leading to the development of pronounced sharp micro-texture. Furthermore, the slipping deformations of alpha-colonies with varying crystallographic orientations during rolling were meticulously analyzed.

With the increasing demands for material performance in modern industries, there is a growing need for aluminum alloys with high strength and good ductility. In addition, energy consumption in power transmission process makes developing transmission materials with high strength and outstanding electrical conductivity more urgent. Here, a heterogeneous lamella structure containing dense Si nanoprecipitates, which provides excellent mechanical and electrical properties, was intentionally introduced into a coarse-grained Al-1%Si alloy through solution treatment, heavy cold rolling, and subsequent annealing. The continuous 97.5 % cold rolled Al1%Si exhibits a yield strength of 276 MPa and a uniform elongation over 3 %. A further improved yield strength of 302 MPa, an ultimate tensile strength of 318 MPa, and a conductivity of 53.3 % IACS are achieved in the sample annealed at 150 degrees C for 1 h. The coarse size and different orientation of the original grains result in the heterogeneous lamella structure. The hetero-deformation induced hardening during tensile deformation offers an outstanding strain-hardening ability, delaying the onset of necking and enabling high strength and good ductility. The dense nanoprecipitates are the main reason for further improved strength and good electrical conductivity. Our results demonstrate the heterogeneous structure resulting in excellent comprehensive mechanical properties and offer a feasible method for preparing high strength and high electrical conductivity using Al-based dilute alloys.