Addition Of Er Research Articles

The Influence of Er and Zr on the Microstructure and Durability of the Mechanical Properties of an Al-Mg Alloy Containing 7 wt.% of Mg.

Al-Mg alloys are characterized by permanent solid solution hardening and can additionally be work-hardened. The high mechanical properties of Al-Mg alloys with above-standard Mg content obtained after plastic deformation processes decrease over time. The addition of minor alloying elements like Er or Zr is an alternative method to improve the durability of mechanical properties and increase the strength of Al-Mg alloys due to densely and evenly distributed dispersoids being formed. In this paper, Al-Mg alloys with above-standard Mg content (7 wt.%) and Zr and Er micro-alloying elements and their influence on the microstructure and durability of the mechanical properties were examined. The cast ingots of AlMg7 alloys were characterized by a smooth surface without cracks. The plastic deformation process in a static compression test resulted in an about 60 HBW increase in the Brinell hardness of all the deformed alloys relative to casting. It was revealed that the addition of Er and Zr significantly improved the mechanical properties and durability of the mechanical properties of the Al-Mg after annealing. The addition of Er or Zr slightly restrained the decrease in the Brinell hardness after annealing but did not inhibit it.

Effect of Er on the Hot Deformation Behavior of the Crossover Al3Zn3Mg3Cu0.2Zr Alloy

The effect of an erbium alloying on the hot deformation behavior of the crossover Al3Zn3Mg3Cu0.2Zr alloy was investigated in detail. First of all, Er increases the solidus temperature of the alloy. This allows hot deformation at a higher temperature. The precipitates resulting from the Er alloying of the Al3Zn3Mg3Cu0.2Zr alloy were analyzed using transmission electron microscopy. Erbium addition to the alloy produces the formation of more stable and fine L12-(Al3(Zr, Er)) precipitates with a size of 20–60 nm. True stress tends to increase with a decline in the temperature and an increase in the deformation rate. The addition of Er leads to decreases in true stress at the strain rates of 0.01–1 s−1 due to particle-stimulated nucleation softening mechanisms. The effective activation energy of the alloy with the Er addition has a lower value, enabling an easier hot deformation process in the alloy with an elevated volume fraction of the intermetallic particles. The addition of Er increases the strain rate sensitivity, which makes the failure during deformation less probable. The investigated alloys have a significant difference in the dependence of the activation volume on the temperature. The flow instability criterion allows better deformability of Er-doped alloys and enables the alloys to be formed more easily. The evenly distributed particles prevent the formation of shear bands with elevated storage energy and decrease the probability of crack initiation during the initial stages of hot deformation when only one softening mechanism (dynamic recovery) is working. The microstructure analysis proves that dynamic recovery is the main softening mechanism.

Diffusion behavior and mechanical properties of the Mg-Er binary system

The Mg-Er binary system, as a new lightweight alloy material system with important research value and prospects for development and application, has attracted much attention from researchers in the field of materials science. Studies have shown that the addition of the rare earth element Er can improve the mechanical strength and heat resistance of magnesium alloys. However, the specific mechanism of the interaction between Mg and Er and its effect on the mechanical properties still need to be studied in depth. A combination of microscopic morphology characterization and nanoindentation experiments were employed to investigate the binary diffusion behavior and mechanical properties of the Mg-Er system between 748 K and 823 K in this research. The results indicate that the growth constant of the diffusion layer increases with temperature, with Mg24Er5 exhibiting a higher growth constant than the sum of Mg2Er and MgEr. Notably, the Mg2Er phase has the lowest growth activation energy (127.81 kJ/mol), which suggests that it is formed first during the initial growth stage due to its relatively low energy barrier. Moreover, the interdiffusion coefficient of Mg24Er5 was found to be the highest. By calculating diffusion activation energy, this sequence of formation (Mg2Er→Mg24Er5→MgEr) is in agreement with the trend of growth activation energy. Additionally, nanoindentation experiments and first-principles calculations were utilized to derive the mechanical properties of the Mg-Er binary system. The investigations unveil that Mg2Er boasts the highest hardness and Young’s modulus. These findings have significant implications for understanding the correlation between structure and properties for the Mg-Er alloy system.

Enhancing strength and ductility of Al–Cu–Li alloys by microalloying both Er and Zr to promote complete transformation from δ′ (Al3Li) to T1 (Al2CuLi) precipitates

The impact of erbium (Er) on grain refinement in Al–Cu–Li alloys is limited by the thermodynamic instability of Al3Er inoculants. Nevertheless, the concurrent addition of both Er and Zr to Al–Cu–Li alloys results in a marked refinement of the average grain size. Er exerts a significant influence on the precipitation sequence within Al–Cu–Li alloys, promoting a complete transition from δ′ (Al3Li) and θ′ (Al2Cu) to T1 (Al2CuLi) precipitates during aging at 120 °C, thereby substantially enhancing both strength and ductility. Through high-resolution transmission electron microscopy (HRTEM), the underlying mechanism of the T1 nucleation by Er microalloying has been elucidated. It has been demonstrated that the presence of Er leads to the formation of solute enrichment regions (SERs) comprising Cu, Zn, Mg and Er. These SERs serve as catalysts for the development of Cu-rich atomic planes along the {111}Al, providing a direct precursor structure for T1 nucleation. Consequently, the synergistic microalloying of Zr and Er not only effectively refines the grain structure but also facilitates the elimination of the δ′ phase. The addition of Er facilitates the complete transformation of the δ′ phase into the strong and ductile T1 phase, resulting in a significant enhancement of the alloy's strength and ductility. Following 100 h of aging at 120 °C, the ultimate tensile strength has increased from 373 to 457 MPa, and the elongation after fracture has risen from 2.8% to 4.9%.

The association between body mass index and molecular subtypes in endometrial carcinoma

ObjectiveThis study aims to investigate the relationship between body mass index (BMI) and molecular subtypes of endometrial carcinoma using an immunohistochemistry (IHC)-based classification approach. MethodsWe analyzed a consecutive series of endometrial cancer cases undergoing surgical staging in southern Alberta (2019–2021). Molecular classification was determined through IHC-based molecular typing, incorporating p53 and mismatch repair (MMR), and further characterized with the addition of ER and PR. BMI associations with molecular classification were assessed using t-tests. Hormone receptor status was further examined in a separate cohort of MMRd endometrial cancer patients undergoing surgical staging at Foothills Medical Centre (Alberta, Canada). ResultsAmong 289 cases, comprising various histological subtypes, the pNSMP subtype exhibited the highest average BMI (33.93 kg/m2) compared to the p53 abnormal subtype (30.40 kg/m2, p = 0.02). The MMRd subtype had an average BMI of 33.22 kg/m2. While there were no significant BMI differences between FIGO grade 1 and grade 2/3 tumours in the pNSMP or MMRd, a trend toward higher BMI in grade 1 tumours versus grade 2/3 tumours in the MMRd was observed (p = 0.13). A separate cohort of 53 MMRd endometrial carcinomas revealed that FIGO grade 1 tumours were associated with higher BMI (p < 0.05) and more frequent ER/PR expression compared to grade 2/3 tumours (p < 0.05). ConclusionsThis study suggests an association between obesity and NSMP endometrial carcinoma. The relationship between BMI and low-grade MMRd endometrial carcinomas with increased ER/PR expression warrants further exploration.

Effect of Er addition on the oxidation behavior of Mg-4Al-0.2Mn alloy at high temperatures

Isothermal oxidation experiments in the range of 450–525 °C were carried out to investigate the effect of different Er contents (0, 0.35, 0.96 and 2.27 wt.%) on the oxidation resistance of Mg-4Al-0.2Mn alloys. The addition of Er extended the incubation period of the alloys. The best oxidation resistance of the alloy was obtained with the Er content of 0.96 wt.%. This is due to (i) the formation of a stable oxide film containing Er2O3 on the surface of the alloy, which inhibits further oxidation of the substrate, and (ii) the improvement of the thermal stability of the substrate. The oxidation kinetics of these alloys at elevated temperatures follow parabolic, linear, and superlinear laws.

Effect of Er addition on the microstructure, mechanical properties and corrosion behaviour of Al-Zn-Mg-Cu alloy manufactured by laser powder bed fusion

The purpose of this study is to gain a deeper understanding of the effects of rare-earth element Er on the microstructure and properties of Al-Zn-Mg-Cu alloy manufactured by laser powder bed fusion (LPBF). Compared with the as-printed Al-Zn-Mg-Cu alloy without Er addition, the as-printed Al-Zn-Mg-Cu-Er alloy with a bimodal grain structure had finer cellular structures and denser precipitation phases, which significantly improved the alloy's mechanical and corrosion resistance properties. The tensile strength of the as-printed Al-Zn-Mg-Cu-Er alloy was 383 MPa, which is 137 MPa higher than that of the as-printed Al-Zn-Mg-Cu alloy without Er addition. It was intended to use T6 heat treatment process to further regulate the mechanical properties of the as-printed alloy, but the formation of Si-rich hard and brittle eutectic phases with sizes of 2–5 μm in the matrix resulted in a decrease in the strength of the alloy, which is contrary to the traditional 7xxx aluminum alloys. Besides, the addition of Er element improved the alloy's corrosion resistance by decreasing the corrosion current density and raising the intergranular corrosion (IGC) resistance, and the maximum intergranular corrosion depth decreased from 174 µm to 68 µm after Er addition.

Effects of addition of Er and Zr on microstructure and mechanical properties of Al–Cu–Mn–Si–Mg alloy

Abstract The effects of addition of Er and Zr on the aging precipitation phase and mechanical properties in cast Al–Cu–Mn–Si–Mg alloy were studied. The addition of Er and Zr can refine the as-cast grains. The average grain size of as-cast alloy containing Er and Zr is 140.60 μm, while the average grain size of as-cast alloy without Er and Zr is 168.54 μm. After T6 heat treatment, the yield strength of the alloy containing Er and Zr reached 334.3 MPa, while the yield strength of the alloy without Er and Zr was only 284.3 MPa. After aging the strengthening precipitates of both alloys contain θ′ phase, Q′ phase and T phase. In the alloys containing Er and Zr the Al3(Er, Zr) phase with L12 structure precipitated during the solution process, which reduced the diameter of the θ′ phase during subsequent aging. After T6 heat treatment, the precipitation strengthening contributed 67.09 % and 61.31 % to the total strength of the alloy with Er, Zr and without Er, Zr, respectively.

Effects of Er addition on the hot deformation behavior and microstructure evolution of AZ31 alloy

AZ31 magnesium alloys typically have poor room temperature ductility after initial deformation. To address this disadvantage, rare earth element Er is introduced to regulate the structure, weaken texture, and promote non-basal slip to achieve plasticization. In this study, the deformation behavior and microstructure evolution during the hot compression process of Er added AZ31 alloy were systematically investigated. Hot compression stress-strain curves showed that the addition of Er reduced the deformation resistance. The constitutive equation and processing map were established. By combining the processing map with the microstructure analysis and texture evolution, an optimal processing area was determined to be 350–400 °C at a strain rate of 0.01 s−1. The influence of Er addition on the twinning behavior, recrystallization mechanism, and slip system of the AZ31 alloy were discussed. During the deformation process, the twinning behavior violates the maximum SF criterion, which is related to severe local stress. Continuous dynamic recrystallization, discontinuous dynamic recrystallization, and twinning induced recrystallization are all detected in the alloy. Through the in-grain misorientation axis and transmission electron microscopy, it can be confirmed that the addition of Er promoted the occurrence of pyramidal <c+a> slip. This is related to the modification of stacking fault energy by Er and the hindrance effect of the second phase containing Er on the basal dislocation.

Effect of HF and ER additions on the mechanical properties and microstructure of AL-MG-SC-ZR system alloys

Effect of HF and ER additions on the mechanical properties and microstructure of AL-MG-SC-ZR system alloys

Corrosion behavior of erbium modified Zn-11Al-3Mg cast alloy in stagnant 3.5 wt% NaCl solution

Zn-11Al and Zn-11Al-3Mg-xEr (x=0, 0.05, 0.1, 0.5) alloys were prepared, and the microstructures and corrosion resistance of the alloys were investigated by scanning electron microscopy (SEM), x-ray diffraction (XRD), and electrochemical methods. The results show that the primary Al-rich phase in Zn-11Al alloys is corroded as the main anode. The electronegativity of the primary Al phase in Zn-11Al-3Mg alloys is higher than the primary MgZn2 phase, and the electronegativity of Al-rich and Mg2Zn11 phases is higher than that of the η-Zn phase in ternary eutectic structure. The primary Al-rich phase and Mg2Zn11 phases in the alloy are corroded as the main anodes. On the other hand, the erbium (Er) reacts with Al to form the AlEr phase, and the AlEr phase has a significant refining and homogenizing effect on the primary Al-rich phase in the Zn-11Al-3Mg alloy. When the content of Er is 0.05%, the primary Al phase transforms into fine discontinuous cellular structure. However, the increase of Er addition promotes the growth of primary Al-rich phase and the reduction of ternary eutectic, which weakens the corrosion resistance of the alloy.

Effect of multi-element synergistic addition on the microstructure evolution and performance enhancement of laser cladded Al–Mg–Zn-(Mn–Cu–Er–Zr) alloy

To satisfy the requirements of formability, strength-toughness, and corrosion resistance for laser additive manufacturing of lightweight aluminum alloy brake discs, this study adopted a thermodynamic design method incorporating Mn, Cu, Er, and Zr elements to develop multi-element Al–Mg–Zn-(Mn–Cu–Er–Zr) alloy. The optimized laser cladding process was employed to prepare a novel alloy sample. The results indicate that a novel T-AlMgZnCuZrEr phase with a distinct structure compared to the conventional T-phase in Al–Mg–Zn alloys was observed in the sample prepared by synergistic addition of Mn, Cu, Er, and Zr. Owing to the significant strengthening and toughening effects of the novel T-phase, the compressive strength and toughness product, along with the corrosion potential of the laser cladded sample reached 26520 MPa2 m1/2 and −0.73 V, respectively, which were 27% and 39% higher than those of Al–Mg–Zn alloy. The precipitation and growth mechanism of the novel T-phase was elaborated, and the kinetic equation for the in-situ precipitation of the T-phase was established. A multi-component design method for strengthening and toughening Al alloy to improve the performance by controlling microstructure through laser cladding was obtained, which provides a valuable reference for laser cladding to prepare lightweight aluminum alloy with high strength-toughness and corrosion resistance.

Developing a High Ductility Mg Alloy Via Non-basal Slips and Intergranular Coordination Induced by Li and Er Addition

Developing a High Ductility Mg Alloy Via Non-basal Slips and Intergranular Coordination Induced by Li and Er Addition

Structural, chemical and biological properties of SiO2-CaO-Er2O3 flexible ceramic nanofibers for biomedical applications

Rare earth-doped bioactive ceramics are promising biomaterials due to their unique optical properties, biocompatibility, antioxidants, and antibacterial activity. In this study, a series of SiO2-CaO-Er2O3 nanofiber mats were fabricated by sol-gel electrospinning. The morphology, flexibility, physicochemical and biological properties of the nanofibers were investigated. The flexibility of the nanofiber mats containing 5 and 10 wt% of Er2O3 was better than that of samples without or with >10 wt% Er2O3. The chemical property assay indicated that addition of Er can lead to changes in the degree of crystallinity and the degree of silica network polymerization, which further affect the flexibility. Photoluminescent spectra showed that the Er-doped nanofibers exist green and near infrared emissions. The in vitro bio experiments demonstrated that Er-doped nanofibers present excellent biocompatibility, and the mineralization experiment demonstrated that Er-doped nanofibers present favorable mineralization activity. Therefore, these SiO2-CaO-Er2O3 flexible nanofibers may be promising candidates for biomedical applications.

Microstructure modification of high magnesium Al-Mg alloys containing Zr, Sc and Er additions subjected to the extrusion process

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Effect of the Solid Solution and Aging Treatment on the Mechanical Properties and Microstructure of a Novel Al-Mg-Si Alloy.

A novel Al-Mg-Si aluminum alloy with the addition of the micro-alloying element Er and Zr that was promptly quenched after extrusion has been studied. The solid solution and aging treatment of the novel alloy are studied by observing the microstructure, mechanical properties, and strengthening mechanism. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques are employed to examine the changes in the microstructure resulting from various solid solution treatments and aging treatments. The best strengthening effect can be achieved when the solubility of the MgSi phase and precipitate β″ (Mg2Si phase) is at their maximum. The addition of Er and Zr elements promotes the precipitation of the β″ phase and makes the b″ phase more finely dispersed. The aging strengthening of alloys is a comprehensive effect of the dislocation cutting mechanism and bypass mechanism, the joint effect of diffusion strengthening of Al3(Er,Zr) particles and the addition of Er and Zr elements promoting the precipitation strengthening of β″ phases. In this paper, by adding Er and Zr elements and exploring the optimal heat treatment system, the yield strength of the alloy reaches 437 MPa and the tensile strength reaches 453 MPa after solid solution treatment at 565 °C/30 min and aging at 175 °C/10 h.

Effect of Er addition on microstructural and mechanical properties of Al-11%Mg2Si alloy

During the solidification of Al-Mg2Si alloy, the eutectic Mg2Si phase with large size and flake-like morphology forms in the structure of the alloy which results in deterioration of mechanical properties; hence, modification/refinement of eutectic Mg2Si phase using alloying elements is a prime concern. Since there is a need to investigate further the characteristics of Al-Mg2Si alloy treated by rare earth additions, this study aims to investigate the influence of different Er concentrations (0.0, 0.1, 0.3, 0.5, and 1.0 wt%) on microstructure and mechanical characteristics of hypoeutectic Al-11Mg2Si metal matrix composite. The composite materials were prepared using an in-situ casting procedure with high purity of the elements. Microstructure characterisation was carried out by optical microscopy, in which an image analyser measured the eutectic Mg2Si cell sizes. The mechanical properties of the fabricated composites were analysed using tensile and hardness tests. The findings demonstrated that the morphology of primary Mg2Si changed with 0.1 wt% Er addition from irregular or dendritic shape to a polyhedral shape and becams uniformly distributed. Microstructural observations also showed that in the Al-11Mg2Si phase, the structure of the eutectic Mg2Si phase was altered from a flake-like structure to a fibrous structure, and the size of the black embedded structures decreased from 188.7 µm in the base alloy to 168.9 µm in the alloy added with 0.1 wt% Er. Further studies on mechanical properties found that 0.1 wt% of Er addition was optimum for enhancing the hardness, UTS, and elongation values, in which the harness value increased from 67.9 to 77Hv, UTS increased from 126 to 131 MPa and elongation (%) from 1.53 to 1.60. The SEM micrographs of the composite fracture surface depicted that with the addition of Er, the brittle fracture mode changed to the ductile mode with fine dimples.

Effect of heat treatment on microstructure and properties of cast and deformed Al alloys with addition of Yb, Er and Zr

The response of isochronal and isothermal ageing on the microstructure, microhardness and electrical properties of as-cast and deformed AlYbEr and AlYbErZr alloys were studied. The addition of Zr does not affect the grain size of the alloys in the initial state. Stability of grain size in both AlYbEr and AlYbErZr as-cast alloys was proved up to ageing at 450 °C for 32 h. On the other hand recrystallized grains were already observed in cold rolled alloys after ageing at 450 °C for 2 h. It was found that Zr supports massive recrystallization of the alloys after ageing at 450 °C. The presence of L12-structured particles with dimensions about 20–100 nm was proved in the initial state of all studied aloys. Investigation of microstructure of the AlYbEr alloy after treatment up to 450 °C and 540 °C proved a presence of particles rich on Er, Yb, some of these pin dislocations. The structure of these particles could be tetragonal with the D019 or D023 lattice. In the AlYbErZr alloy many fine L12 particles (contain Er, Yb and Zr) were observed. The L12 particles were observed after ageing at 640 °C for 4 h in both alloys. The addition of Zr to the alloy highlighted the core-shell structure of these particles, moreover some of them have the double core-shell structure in the AlYbErZr alloy, where the outer shell contains Yb and Er, the inner shell contains Zr and Yb and Er was detected in the core.

Microstructure and mechanical properties of a novel Al–Mg–Er–Zr-Sc alloy fabricated by selective laser melting

In this work, Er–Zr-Sc modified Al–Mg alloy, manufactured by selective laser melting, offers excellent mechanical properties, due to the formation of a desirable microstructure and the synergistic effects of multiple strengthening mechanisms. The microstructure in as-built and aged alloys have been characterized by scanning electron microscopy and transmission electron microscopy. The results show that the microstructure of alloy is composed of equiaxed grains (∼0.7 μm in diameter) along the boundary of molten pool and columnar grains (∼1.46 μm in width) inside the molten pool. Al3(Sc,Zr) particles serve as nucleation sites to promote the nucleation of equiaxed grains, and Al3(Er,M) eutectic phases and other compounds at the grain boundaries inhibit grain growth, both of which greatly refine the grains and bring significant grain boundary strengthening and Orowan strengthening effect. During the aging process, coherent Al3(Er,Zr,Sc) nano-precipitates are dispersedly precipitated from the Al matrix, which plays a key role in improving the mechanical properties of the aged alloy, and then the alloy reaches a yield strength of 530 MPa, a tensile strength of up to 542 MPa, and an elongation of over 12 %. Under the combined addition of Er, Sc, and Zr, and the influence of multi-element interaction, the alloy has high-density secondary phases and extremely fine grains, which are the main sources of reinforcement.

Influence of erbium addition on microstructure and performances of AlSi10Mg alloy prepared by selective laser melting

The effect of rare earth addition on the microstructure and mechanical performances of as-cast and wrought Al alloys has been attracting increasing attention recently. Rare earth addition has great potential in modifying the structure and improving the properties of materials. However, there are currently few reports about the effect of rare earth addition on the microstructure and performances of Al alloys prepared via selective laser melting. Here, AlSi10Mg alloys were manufactured using selective laser melting, and the effect of Er addition was investigated. The results indicate that Er addition leads to α-Al refinement and modifies the minority Si phase. The formation of the Al3Er phase induced by Er addition enhances the strength of the material. Modification of the Si phase also increases ductility. This strategy can help improve the mechanical performance of aluminum alloys prepared via selective laser melting.