Cold spray deposition exploits the phenomenon of impact bonding for solid-state consolidation of metallic microparticles. However, the particle interfaces in the deposits are susceptible to crack propagation under mechanical stresses, which results in inferior ductility. In this work, we seek to develop insights into splat-substrate interface bonding by in-situ micromechanical investigations. A miniaturized

Tensile deformation and damage evolution of a metastable β titanium alloy (Ti–5Cr–4Al–4Zr–3Mo–2W–0.8Fe) with lamellar microstructure are studied by in-situ tensile test under scanning electron microscopy. In the tensile process, the main deformation modes include the dislocation slip, phase interface shear and grain boundary shear, and the geometrical orientation of α lamellae determines the activation

A carbide-free bainite steel of 0.29C–2.50Si-1.50Mn-1.0Mo-0.97Cr (wt.%) with no voids and cracks was fabricated via laser powder deposition (LPD). Different post-treatment plans were conducted and then microstructures and properties of the steel were studied through optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffractometry (XRD), transmission electron microscopy (TEM), hardness

Directed energy deposition (DED) of Inconel 718 is a promising process for the reconstruction of aerospace components, but a large number of Laves phases precipitated in inter-dendrites can impair the mechanical properties of the reconstructed parts. This paper puts forward a gradient laser power (GLP) deposition method to tailor the morphology and content of the Laves phase effectively, thereby enhancing

Ultra-high strength steel (UHSS) has been widely applied in a variety of industries to satisfy lightweight requirements. For now, it is still a challenge to realize both high strength and excellent toughness in welded joints of UHSS, especially in the coarse grain heat affected zone (CGHAZ). In this research, an innovative step cooling process was proposed to control microstructures and mechanical

Laser hot wire cladding (LHWC) technology has been proved to be a very efficient laser cladding manufacturing process due to its advantages of fast deposition rate, high material utilization rate, and less environmental pollution. In this study, LHWC technology was used to prepare multiple layers of 308L stainless steel coatings on ordinary mild carbon steel substrates. The microstructure of the weldment

In this work, rotating bending fatigue, scanning electron microscope in-situ fatigue, pre-fatigue (and post-fatigue) electron backscatter diffraction tests were carried out for rolled Ti–6Al–4V alloys. The macrozone sizes and orientations of the materials were classified and the effect of macrozones on fatigue cracking behavior and fracture mechanisms was studied. The results indicated that intra-granular

The hydrogen effect on a X65 carbon steel was investigated using in-situ electrochemical nanoindentation approach. The alterations in elastic behavior, pop-in load, and hardness under hydrogen-free and hydrogen-charged conditions in both ferrite and bainite were compared and discussed. The results demonstrated a non-affected elastic behavior by hydrogen in both microconstituents. The homogeneous and

Severe plastic deformation (SPD) processes have received less attention at low temperatures (sub-zero and cryogenics). Hence, in this study, SPD of a commercially pure aluminum (AA1050) through Multi-Directional Forging (MDF) at Low-Temperature (LTMDF) and Room-Temperature (RTMDF) is investigated for different strains. Multi-directionally forged (MDFed) samples were annealed at 150, 250, 350, and 450 °C

The fracture surfaces and cracks in technically pure iron, Fe-2.5% Si alloy and low-carbon steel grade S235JR produced by quasi-cleavage (QC) hydrogen-assisted cracking (HAC) as well as by true cleavage (TC) were studied and compared on different scales through the quantitative and qualitative fractographic and side surface examinations. The mixed type QC/TC fracture surfaces were obtained using two-step

In the present work, for the first time, the effect of asymmetric rolling at room temperature on the microstructural evolution, texture, hardness, tensile properties, and fracture surface of AA7075 alloy was investigated. It was found that the width of grains significantly decreased to 2.6 μm by 60 % asymmetric rolling. Also, shear bands in the RD-ND (rolling direction – normal direction) plane of

The effect of temperature and cyclic loading on stress relaxation (SR) behavior of Ti–6Al–4V titanium alloy was studied by uniaxial tensile test. SR limit and rate vary with increasing the temperature and cyclic loading times. The microstructural variations were observed by scanning and transmission electron microscopes. Unstable SR behavior happens at 450–550 °C, which becomes obvious with the increase

The effect of specimen inclination angle with respect to building direction on the tensile properties of a selective laser melt 316L alloy was investigated. Tensile test specimens were fabricated with the angles between 0° to 90° at 15° intervals using a rotation scanning. In addition, 316L alloy test specimens were generated in the ANSYS 2020R1 additive module and tensile tested in LS-DYNA in order

Nanotructural evolution and grain refinement leading to heterogeneous bimodal structure were investigated during thermomechanical processing in carbon-containing FeMnCoCr twinning induced plasticity (TWIP) high-entropy alloy (HEA). The homogenized single-phase face-centered cubic alloy with the stacking fault energy of 19.4 ± 2 mJ m−2 was cold rolled up to thickness reduction of 84 % and annealed at

In this study, we prepared a Zn-0.8Mg-0.2Sr (wt. %) alloy and processed it by ECAP. The evolution of the microstructure during the processing was observed and discussed in detail. The obtained results revealed the continuous dynamic recrystallization as the prevailing recrystallization mechanism. It affected all the aspects of the microstructure, namely the grain size, residual stresses, and dislocation

In the trend of integration of structure and function, novel thermal management materials are urgent to be developed owning good mechanical properties as well as excellent thermal properties. In this work, a complete and dense copper (Cu) coating with a thickness of 400 nm was deposited on the surfaces of graphite films (GFs) by ultrasonic-assisted electroless plating, which can improve the surface

The bimodal microstructure of a metastable β Ti–7Mo–3Nb–3Cr–3Al (Ti-7333) alloy was successfully tuned through various thermomechanical processing steps, to achieve strength and ductility combinations, in the range between 903 and 1443 MPa and 2.9 % and 17 %, respectively. The influence of the microstructural variables on the deformation micro-mechanisms and fracture mechanisms were further elucidated

This article presents the Laser Beam Direct Energy Deposition (DED-LB) process as a method to build a graded austenitic-to-martensitic steel junction. Builds were obtained by varying the ratio of the two powders during DED-LB processing. Samples with gradual transitions were successfully obtained using a high dilution rate from one layer to the next. Long austenitic grains are observed on the 316 L

The elevated temperature tensile properties of SLM IN718 were measured as a function of strain rate and test temperature to better understand the time-dependent and thermal aspects of environmental sensitivity. SLM and wrought materials were solution treated, aged, and tested over the range of 550–750 °C and 10−3 to 10−6 s−1. The SLM material tested across all conditions had inferior strength and ductility

In this work, various alloy compositions of immiscible copper-tantalum (Cu–Ta) are systematically studied to understand the interplay between cluster stability, precipitation hardening, and the overall stability of the matrix's average grain size. An alloy composition of Cu-3at.%Ta is found to exhibit dramatic improvements relative to other Ta contents only after exposures of more than 300 hours at

Al-based composites with enhanced thermomechanical properties are in high demand. However, obtaining a uniform distribution of the strengthening phase in the metal matrix and achieving a strong metal/ceramic interface is still a great challenge. In this work, nanoAl/nanoSiC powder mixtures after high-energy ball milling were treated with Ar microwave plasma. Plasma processing was designed to remove

This research reports a promising bio-applicable new Ti35Zr15Nb25Ta25 (at.%) medium entropy alloy (MEA) designed with an atomic mismatch value (δ) of 4.0 % through replacing 10 at.% Zr with 10 at.% Ti in its parent equiatomic TiZrNbTa MEA (δ = 4.84 %). The as-cast MEA shows a single body centred cubic (BCC) phase with ∼81 % of its solidification grain boundaries (SGBs) having misorientation angles

This study presents a unique melting strategy in electron beam-powder bed fusion of Alloy 718 to tailor the grain morphology from the typical columnar to equiaxed morphology. For this transition, a specific combination of certain process parameters, including low scanning speeds (400–800 mm/s), wide line offsets (300–500 μm) and a high number of line order (#10) was selected to control local solidification

As is known, solidification rate has an obvious effect on microstructure and property. Mechanical properties of Fe-Al-Ta eutectic composites at the solidification rates of 650 μm/s, 700 μm/s, 800 μm/s and 900 μm/s were studied in the present paper. Microhardness, tensile property and fracture toughness of Fe-Al-Ta eutectic composites at different solidification rates were studied respectively. Microhardness

This study aimed to systematically investigate the microstructure evolution of the nail-shaped weld on electron beam welded joint of Ti–6Al–4V alloy. The microstructure evolution demonstrated that the needle martensitic α′ phases constituted the microstructure in the fusion zone, in which the grain size decreased in the depth direction, and the Widmannstätten structure lamellar α phases covered the

W alloys prepared via oxide dispersion strengthening have shown enhanced mechanical performance. In this paper, W-1.10 vol% Zr-2.00 vol% Y2O3 (WZY) and W-1.10 vol% Zr-2.00 vol% Er2O3 (WZE) were fabricated to investigate the effects of formation of complex oxide dispersions on mechanical properties and microstructure of multi-doped W alloys. By controlling the atomic ratio of added ZrH2 and rare earth

High-temperature performance is a key factor to concern for the application of cast Al–Si alloys. The evolution of microstructures and mechanical properties of a multiphase Al–Si–Cu–Mg–Ni–Ce alloy during tension in a temperature range from 25 °C (ambient temperature) to 425 °C was investigated. The results show that the main strengthening precipitates of the alloy are θ′ and Q phases. They are stable

We describe here the high cycle fatigue (HCF) behavior of a rail steel comprised of multiphase structure of bainite, martensite and film-like retained austenite, which was processed by the quenching and tempering (Q&T) heat treatment process. Conventional mechanical properties of experimental materials were determined, and the high cycle fatigue S–N curve of rail steel was obtained through ultrasonic

Nano SiC layer is innovatively introduced into carbon nanotubes/Al (CNTs/Al) interface to improve the interface bonding and control the interface reaction between CNTs and Al matrix. SiC-cladded CNTs (CNTs@SiC) reinforced aluminum matrix composites (AMCs) were prepared by variable speed ball milling process-powder metallurgy-hot extrusion route. The results show that the introduction of SiC layer hinders

In this study, the stir casting method was used to prepare aluminum matrix bimodal syntactic foams by mixing alumina hollow spheres of different size ranges. Alumina hollow spheres of 1.0–4.0 mm were divided into six size ranges. In bimodal syntactic foams, the hollow spheres of different size ranges were mixed in equal volume to ensure that their average diameter was almost the same, or the hollow

Dual-phase microstructures arising out of eutectic reactions offer several advantages: ease of casting, composite properties and tunable characteristic length scale of the phases. Eutectic high entropy alloys (EHEA) with a multi-component solution phase and a hard intermetallic phase are candidate materials to identify alternate high-temperature materials. Alloying elements can be chosen to improve

In this paper, the mechanical properties and microstructure of hot-rolled low carbon steel containing Ti–Mg oxide inclusions as well as the effect of austenite grain size on acicular ferrite (AF) nucleation and the nucleation mechanism of AF were studied. The results indicated that the dominant inclusions in Ti–Mg deoxidized steel comprised Ti–Mg–Mn–O·MnS, which effectively promoted the nucleation

Intermetallic compounds (IMCs) formation during friction stir welding (FSW) of dissimilar metals such as aluminum (Al) and steel (St) is known to cause a reduction in the joint strength. IMCs are brittle and act as the preferential sites for fracture propagation. In the present study, a modified FSW was used to join a commercially pure Al to a mild carbon St. Several characterization techniques were

A periodic layer (PL) structure characterized with interval distribution of austenite for 17-4 PH steel is achieved by the laser direct metal deposition and aging. The synergism of strain partitioning hardening and austenitic transformation-induced plasticity contributes crucially to the excellent strength-ductility combination in the PL structured 17-4 PH steel.

Simultaneously increasing the strength and ductility of hot work die steels is of significant interest for broad applications. The in-situ development of a nano-phase in steels is a promising method for achieving this objective. However, little success has been reported so far. In this study, trace amounts of TiC nanoparticles were successfully introduced into a high-Cr hot work die steel (HHD) through

A novel high strength and high-density steel was obtained by the addition of tungsten element. Compared with traditional steel, the novel steel exhibits a higher density (＞9 g/cm3), while maintaining high strength, and good ductility. Small precipitates of the μ phase dispersed in the matrix.

Vacuum hot-rolled bonding (VHRB) titanium (Ti)-steel clad composites have been increasingly serving in both severe corrosion and heavy load conditions, and their overall properties severely depend on the microstructure of interfacial reaction layer. Notably, introducing an appropriate interdiffusion barrier to minimize the brittle Fe–Ti intermetallics has still been a popular scheme for optimizing

The tensile and Charpy impact properties of four strip samples from two different B-added low-C ultra-high-strength steel strips (Al-treated and Ti-treated), coiled at two different temperature ranges (360–380 °C and 450–460 °C), have been evaluated and correlated to the microstructural parameters, dislocation density, and the intensity of high-angle boundaries. The effects of coiling temperatures

The present study investigates low cycle fatigue behaviour of the metastable austenitic 304L steel in two variants: i) as-received and ii) after additional solution annealing at 1050 °C/30 min. The applied heat treatment resulted in a decrease of δ-ferrite volume fraction and slight grain coarsening. After the solution annealing, significantly prolonged fatigue life within the whole range of studied

Challenges are encountered with the laser-blown-powder directed-energy-deposition (LBP-DED) of high-performance alloys such as IN718. Complications that arise include the formation of undesired phases, irregular microstructure, and pronounced texture leading to anisotropic elastic properties. To mitigate these issues, deposition parameters and post-processing treatments must be carefully selected to

In the coarse grain heat-affected zone (CGHAZ) of a low carbon Mo–V–Ti–B steel subjected to a simulative welding thermal cycle with a heat input as high as 75 kJ/cm, the influence of an increase in nitrogen content from 0.0085 to 0.0144 wt% on the microstructures and impact properties of the steel was comparatively estimated using Gleeble-3800 simulation, microstructure characterization and impact

The tensile properties and deformed microstructures of Ti–5Al–1V–1Sn–1Zr-0.8Mo (Ti5111) alloy with a bimodal structure under different deformation temperatures are investigated. As the deformation temperature decreases from 0 °C to −196 °C, the tensile strength, and elongation of Ti5111 increase simultaneously. The distinguishing characteristic of the deformed structure is the presence of {101‾2}101‾1

It is challenging to simultaneously achieve nearly full density and high strength in refractory alloys using selective laser melting (SLM). In this study, the achievement of ultrahigh-strength resulting from nearly full density has been reported in beta-type titanium alloy by controlling the melt pool mode in SLM. The melt pool mode was divided into the conduction and keyhole modes, which were determined

A lean duplex stainless steel material (2304-grade) in its base metal and electron beam (e-beam) welded conditions were studied microstructurally and mechanically as a function of irradiation conditions to evaluate its use as a structural material at low temperatures (60–100 °C). Neutron irradiation up to a fluence of 1.40 × 1019 n/cm2 (E > 0.1 MeV) or ~0.011 dpa decreased the total elongation of both

In this study, a functionally graded material (FGM) was fabricated using a powder bed fusion additive manufacturing technique. The FGM evaluated was Ti–6Al–4V, due to its importance in the medical device and aerospace sectors. The microstructure at selected build locations was analysed using both scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) techniques, where a gradient

We study the influence of different grain size (density of grain boundaries) on the way of phase transformations in the surface layers of 316 L-type austenitic stainless steel under ion-plasma treatment. Using thermomechanical treatments, we fabricated a series of specimens possessing a single-phase austenitic structure, close density of the defects of the crystal lattice and different grain sizes

In this study, the effect of ARB process on the microstructural evolution and precipitation characteristics of an Al–Ag-Sc alloy was explored. Four and eight cycles of the ARB process were applied on a solution treated Al–Ag-Sc alloy. As well, artificial aging heat treatment was applied on the solution treated and the severe plastically deformed specimens in the temperature range of 100 °C–500 °C.

The coarsening behavior of the γʹ precipitates and compression deformation mechanism of the γʹ-strengthened CoNi-base superalloys are investigated. By substituting 1 at.% Ta for 1 at.% W, the 4W2Ta alloy exhibits a higher γʹ solvus temperature of 1218 °C and a lower mass density of 8.93 g/cm3. During the aging process from 900 to 1000 °C, both of the 5W1Ta and 4W2Ta alloys show stable γ/γʹ two-phase

Laser metal deposition (LMD) with a coaxial powder feeding technology has been applied to fabricate pure aluminum alloy (AlSi7Mg) and low oxidation graphene aluminum matrix (LOG-Al) composites with low oxidation graphene (LOG) contents of 0.05 wt % and 0.1 wt % after the powder was prepared by wet ball milling. The LOG-Al composites showed improvements in all properties including hardness, tensile

Hot compression testing was performed on specimens of an Fe–30Mn–9Al–1Si-0.9C-0.5Mo wt.% low density steel which were extracted from an industrial casting with large grain size (320 ± 50 μm). Grain boundaries act as nucleation sites for dynamic recrystallization in the present material and the large grain size results in fewer nucleation sites, which delays dynamic recrystallization to larger strains

Mechanical response of transformation-induced plasticity (TRIP)-enabled metastable high entropy alloys that display austenite (γ) to martensitic (ε) phase transformation under uniaxial tension is characterized by a constant work hardening segment preceded and succeeded by stages of gradual drop in work hardening. A four-parameter empirical model based on the nature of the work hardening curve is developed

Cracks can occur in the welded joints of weathering mild steel during the conventional welding process, due to the high phosphorus content. The present work studies the microstructure and mechanical properties of weathering mild steel by friction stir welding (FSW), which makes welding possible at lower temperature. The weathering steels SMA490-AW and SPA-H with different chemical compositions were

Hybrid additive manufacturing, incorporating additive manufacturing (AM) and other thermo-mechanical processes, has been developed to improve AM mechanical properties by modifying the as-deposited microstructure and eliminating defects. Additive manufactured parts present strong anisotropic properties, as shown by the anisotropic columnar grain morphology and texture. Samples of AM Inconel 718 were

To evaluate the effects of microstructural factors on the plastic behavior of Ti–6Al–4V alloys, micro-cantilevers featuring several grains were machined using a focused ion beam. The equiaxed structure (a mixture of equiaxed α phase and intergranular β phase) and bimodal structure (a mixture of an equiaxed α phase and lamellar phase) were examined to verify the microstructural effects. To determine

Based on the hypothesis of lattice distortion, compositional complexity of high entropy alloys (HEAs) induces severe lattice distortion. Recent studies on the experimental and theoretical approaches to lattice distortion have been made to evaluate this hypothesis. However, the understanding of this effect is not complete due to their highly complex compositions and limited direct evidence. This work

Ti–Nb alloys have been widely researched for biomedical applications because of their excellent mechanical properties, corrosion resistance, and superior biocompatibility. In this investigation, the influence of oxygen content on the microstructure and mechanical properties of Ti–Nb alloys with relatively low Nb contents was evaluated. Arc-melted Ti–Nb–O ingots (Nb contents were 15, 17.5, 20, and 22