DRX Grains Research Articles

Effect of microalloying by Ca on the microstructure and mechanical properties of as-cast and wrought Mg–Mg2Si composites

The effects of calcium addition at microalloying levels and hot extrusion process on the modification of the microstructure and enhancement of the mechanical properties of the Mg–3Si metal matrix composite (MMC) were studied. Electron backscatter diffraction (EBSD), X-ray diffraction (XRD), cooling curve thermal analysis, simulation based on the finite element method (FEM), thermodynamics predictions, tensile testing, and optical microscopy were used for characterization. The Ca addition modified the primary and eutectic Mg2Si phase, resulted in grain refinement of the matrix, led to better tensile properties in the as-cast condition, and gradually changed the isothermal eutectic reaction to a non-isothermal route. Moreover, hot extrusion led to the extreme grain refinement induced by dynamic recrystallization (DRX) and the break up of the eutectic structure into fine and well-distributed particles. For the Ca-containing composites, the modified primary Mg2Si particles enhanced the particle stimulated nucleation (PSN) mechanism, leading to the formation of a higher volume fraction of DRX grains with more random orientations (crystallographic texture). Accordingly, remarkable improvements in tensile properties (such as tensile toughness) were observed via extrusion of the modified in situ composites.

Study on the Dynamic Recrystallization Behavior of 47Zr-45Ti-5Al-3V Alloy by CA-FE Simulation.

The dynamic recrystallization (DRX) behavior of 47Zr-45Ti-5Al-3V alloy was studied by using the experiment and numerical simulation method based on DEFORM-3D software and cellular automata (CA) over a range of deformation temperatures (850 to 1050 °C) and strain rates (10−3 to 100 s−1). The results reveal that the DRX behavior of 47Zr-45Ti-5Al-3V alloy strongly depends on hot-working parameters. With rising deformation temperature (T) and decreasing strain rate (), the grain size () and volume fraction () of DRX dramatically boost. The kinetics models of the and of DRX grains were established. According to the developed kinetics models for DRX of 47Zr-45Ti-5Al-3V alloy, the distributions of the and for DRX grains were predicted by DEFORM-3D. DRX microstructure evolution is simulated by CA. The correlation of the kinetics model is verified by comparing the and between the experimental and finite element simulation (FEM) results. The nucleation and growth of dynamic recrystallization grains in 47Zr-45Ti-5Al-3V alloy during hot-working can be simulated accurately by CA simulation, comparing with FEM.

Hot Deformation Behavior and Microstructure Evolution of Fe-5Mn-3Al-0.1C High-Strength Lightweight Steel for Automobiles.

The hot deformation behavior of a newly designed Fe–5Mn–3Al–0.1C (wt.%) medium manganese steel was investigated using hot compression tests in the temperature range of 900 to 1150 °C, at constant strain rates of 0.1, 1, 2.5, 5, 10, and 20 s−1. A detailed analysis of the hot deformation parameters, focusing on the flow behavior, hot processing map, dynamic recrystallization (DRX) critical stress, and nucleation mechanism, was undertaken to understand the hot rolling process of the newly designed steel. The flow behavior is sensitive to deformation parameters, and the Zener–Hollomon parameter was coupled with the temperature and strain rate. Three-dimensional processing maps were developed considering the effect of strain and were used to determine safe and unsafe deformation conditions in association with the microstructural evolution. In the deformation condition, the microstructure of the steel consisted of δ-ferrite and austenite; in addition, there was a formation of DRX grains within the δ-ferrite grains and austenite grains during the hot compression test. The microstructure evolution and two types of DRX nucleation mechanisms were identified; it was observed that discontinuous dynamic recrystallization (DDRX) is the primary nucleation mechanism of austenite, while continuous dynamic recrystallization (CDRX) is the primary nucleation mechanism of δ-ferrite. The steel possesses unfavorable toughness at the deformation temperature of 900 °C, which is mainly due to the presence of coarse κ-carbides along grain boundaries, as well as the lower strengthening effect of grain boundaries. This study identified a relatively ideal hot processing region for the steel. Further exploration of hot roll tests will follow in the future.

Effect of thermo-mechanical processing parameters on the dynamic restoration mechanism in an Mg-4Y-2Nd-1Sm-0.5Zr alloy during hot compression

Microstructure evolution and dynamic restoration mechanism of solution-treated Mg-4Y-2Nd-1Sm-0.5Zr alloy have been studied under three TMP parameters consisting of deformation temperatures (350–500 °C), strain rates (0.01–5 s−1), and strains (0.2, 0.4, and 0.8). A strong dynamic softening is observed in all stress-strain curves, even at higher strain rates (1 and 5 s−1) due to an adiabatic heating effect. Various stress-strain curves are applied to construct a processing map and develop an Arrhenius-type constitutive equation. With the prediction of the processing map, an optimal processing domain has been determined to be the temperature range 450–500 °C and strain rate range 0.01–0.1 s−1 at a strain of 0.8. The volume fraction of DRX grains is the largest in the corresponding domain of high temperature and low strain rate. For the effect of TMP parameters on the dynamic restoration, the discontinuous dynamic recrystallization (DDRX) and continuous DRX (CDRX) synergistic effect occur throughout the whole process at high temperature and high strain rate. In terms of high temperature and low strain rate, DDRX characteristics at a low strain and then the DDRX + CDRX synergistic effect is observed at a higher strain. Although the DRX process is weak at low temperature and low strain rate, deformation twins have occurred and provided nucleation sites for DRX grains.

Modeling and simulation of dynamic recrystallization in super austenitic stainless steel employing combined cellular automaton, artificial neural network and finite element method

A cellular automaton (CA) model for dynamic recrystallization (DRX) is established by employing Moore’s neighboring rule to predict flow stress, DRX grain size (DDRX) and DRX fraction (XDRX). The CA model has been optimized for super austenitic stainless steel at different strain rates (0.001–10 s−1) and temperatures (1173–1423 K) under isothermal deformation conditions. The output of the CA simulation has been used for establishing ANN-based constitutive models. The trained ANN-based constitutive models have been further implemented in FEM software (ABAQUS 6.14) to evaluate flow behavior and microstructure response of the alloy under various non-isothermal deformation conditions. The conventional CA (CAC) model has failed to provide a good depiction of the microstructure evolution, as it revealed a very low correlation coefficient (R) for XDRX (R ~ 0.75) and DDRX (R ~ 0.8). This inaccuracy of the model could be related to its inherent inability to consider the effect of solute drag on grain growth and DRX kinetics. Therefore, a modified cellular automata (CAM) model has been developed by introducing a new temperature-strain rate-dependent mobility parameter for numerically considering the solute drag effect. Employing non-isothermal simulations, the CAM model has revealed a higher correlation coefficient than the CAC model for predicting XDRX (R ~ 0.95) and DDRX (R ~ 0.98). Moreover, the developed CAM model has also predicted the flow behavior of the alloy in the entire domain investigated, revealing a higher correlation coefficient (R ~ 0.987) and a low average absolute relative error (8.6%).

Design of a hot deformation processing map for a Ni-free, N-bearing austenitic stainless steel

The hot deformation characteristics of a FeCrMnN austenitic stainless steel containing 0.28 wt.% nitrogen (N) was investigated by hot compression tests using a Gleeble simulator in the temperature range of 800−1200 °C and at constant true strain rates of 0.01–10 s−1 with all specimens deformed to ∼0.9 true strain. The influence of deformation conditions on microstructural mechanisms and phase transformations was characterized. A processing map based on dynamic materials modelling (DMM) was designed and interpreted for predicting the domain of stable flow for safe, defect-free hot deformation. The results revealed the occurrence of dynamic recrystallization (DRX) in a domain extending over the temperature and strain rate ranges of 1100−1200 °C and 0.1–1 s−1, respectively, with the efficiency of power dissipation (η) of 45–55 %. Decreasing temperature and increasing strain rate led to a reduction in DRX grain size following microstructural reconstitution. Another small deterministic domain of 820−1000 °C and 0.01−0.05 s−1 was identified showing occurrence of partial DRX in shear bands leading to formation of a mixed microstructure. The instability criteria delineated the regime of unstable flow covering a large part of the processing map extending over low temperatures (800−950 °C) and high strain rates (0.1–10 s−1) that must be avoided during processing.

Modelling dynamic recrystallisation in magnesium alloy AZ31

In this paper, a dynamic recrystallisation (DRX) viscoplastic self-consistent (VPSC) model is created to predict the continuous DRX (CDRX) and twin-assisted DRX (TDRX) behaviour within an AZ31 magnesium (Mg) alloy over temperatures ranging from 25 °C to 200 °C. At this temperature range, the active deformation mechanisms and physical phenomena participating in the strain accommodation and texture evolution of Mg alloys are: a basal slip, a prismatic slip, c+a pyramidal slip, {101‾2} tensile twinning, and DRX. In order to predict which deformation modes are activated for this particular alloy and their influence on the DRX mechanism, a temperature sensitive VPSC model combined with a dislocation density hardening law and a composite twin grain model is used. The model is validated against a comprehensive set of experimental data including flow curves and texture evolution, realised on a hot-rolled AZ31 Mg alloy deformed at different temperatures between 25 °C and 200 °C under uniaxial tensile loads parallel to, perpendicular to, and at 45° offset from the rolling direction of the processed material. Furthermore, a parametric study into parameters such as grain size, dislocation density, and crystallographic orientation of the nucleating DRX grains influencing the DRX kinetics and, subsequently, the plastic material behaviour of the alloy is carried out and discussed.

Effect of Zener-Hollomon parameter on microstructure evolution of a HEXed PM nickel-based superalloy

The microstructure evolution of a hot extrusion (HEXed) powder metallurgy (PM) nickel-based superalloy was investigated by hot compression tests under different deformation conditions. Optical microscope (OM), electron backscatter diffraction (EBSD) technique and transmission electron microscope (TEM) were applied to investigate the effect of Zener-Hollomon (Z) parameter on the microstructure evolution and nucleation mechanisms of dynamic recrystallization (DRX). The results show the stress-strain curves of the experimental superalloy exhibit obvious characteristics of DRX. Microstructure observations reveal that with the decrease of the Z parameter, both the degree of DRX and the size of DRX grains for the experimental superalloy gradually increase. The nucleation mechanism of DRX of the experimental superalloy is related to the Z parameter. Under the condition of lower Z value, discontinuous dynamic recrystallization (DDRX) characterized by bulging of grain boundaries is the main mechanism of DRX, while continuous dynamic recrystallization (CDRX) is considered to be an auxiliary mechanism for DRX nucleation in hot deformation. The existence of twins and γ' phase also has a major effect on the DRX nucleation mechanism of the experimental superalloy. Under the condition of higher Z value, CDRX and DDRX occur simultaneously, while CDRX characterized by progressive subgrain rotation can also be regarded as an important nucleation mechanism of DRX.

Evaluation of the deformation behaviors and hot workability of a high-strength low-alloy steel

Abstract The flow behaviors of 300M steel are studied by hot compression experiments at the deformation temperatures of 1173~1423 K and strain rates of 0.01~10 s−1. The flow stress curves are corrected to eliminate the effects of adiabatic heating and friction on the flow stress. Based on the corrected flow stress curves, a modified constitutive model is established to quantify the flow behaviors of 300M steel accurately. It is found that the apparent activation energy is a function of deformation temperature and strain rate, and the stress exponent is a function of deformation temperature. The dynamic recrystallization (DRX) map is constructed to analyze the microstructure evolution mechanism, which is made up of four parts including dynamic recovery (DRV), partial DRX (P-DRX), full DRX (F-DRX), and grain coarsening (GC). Besides, the average grain size maps for DRX grains and all grains are constructed to analyze the effects of the DRX process on the microstructure and optimize the microstructure of the alloy. The 3D instability map and 3D power dissipation map are constructed to evaluate the hot workability. The instability region corresponds to high strain rates and low deformation temperatures. The peak domain of power dissipation efficiency varies with the increaseing strain, which can be ascribed to the development of the DRX process and microstructure evolution. There are two suitable processing regions according to the processing map. Combining with the degree of DRX, and the size and distribution of austenite grains, the deformation parameters are optimized. The optimized deformation parameters are the strain rate of 0.36~10 s−1 and deformation temperature of 1382~1423 K, and the strain rate of 0.01~0.07 s−1 and deformation temperature of 1243~1323 K. The power dissipation efficiency is an important index to evaluate the DRX degree and flow instability. When the power dissipation efficiency is below 25%, the flow instability of 300M steel occurs easily and the DRX develops inadequately.

Microstructure Evolution and Thermal Stability of AZ31 Alloy Deformed by Multi-Pass DSR

Experiments were conducted to investigate the microstructural evolution of AZ31 alloy when deformed by multi-pass differential speed rolling (DSR) using the simplest modification of route A passing sequence. Microstructural observations were taken on all three planes of the sample to obtain a three-dimensional view. Based on quantitative microstructural analysis, the counts of the fine DRX grains increased with increasing number of DSR passes, while the fine DRX grains’ size was consistent in each pass. These results signified that the refinery process was attributed to dynamic recrystallization. Thermal stability was perceived by examining the evolution in microstructure and microhardness value of the 4-pass DSR sample during isochronal annealing over a range of temperature from 423 to 723 K. The increase in distortion energy with multi-pass DSR resulted in the decrease in critical temperature for the initiation of recrystallization upon annealing at 423 K, which induced an immediate drop in microhardness.

Microstructure evolution and a unified constitutive model for a Ti-55511 alloy deformed in β region

The microstructure evolution of a Ti-55511 alloy deformed at high temperatures (from 1163 K to 1253 K) and wide strain rate range (from 10 s−1 to 0.001 s−1) is studied by isothermal compression tests. Based on the sensitivity of dislocation density to deformation conditions, a unified constitutive equation is established to describe the evolution of flow stress, grain size and dynamic recrystallization (DRX) fraction. The results show that the initial grain boundaries are serrated, and the sub-grains and DRX grains are formed with the further deformation. Furthermore, the discontinuous and geometric DRX mechanisms are dominant recrystallization mechanism. Increasing the deformation temperature can increase the DRX fraction and sub-grain size. However, the abnormal growth of β grains occurs at 1253 K. The DRX fraction decreases with the increased strain rate. Meanwhile, the chain-like small DRX grains and the flow localization occur at high strain rates. Also, the established constitutive model is verified by the experimental results, and the correlation coefficient is 0.9929, indicating the excellent prediction ability of the established constitutive model.

Hot tensile deformation behavior and microstructural evolution of 2195 Al–Li alloy

Hot tensile deformation behavior of 2195 Al–Li alloy was investigated under the strain rate of 0.1 s−1 in the temperature range of 440–500 °C, and the characteristics of microstructure evolution were discussed. At 440 °C, the degree of dynamic recrystallization (DRX) was relatively low at ε~0.2 and 0.4. The fraction of high angle grain boundary (fHAGB) showed an increase with the increasing strain. Besides, large amounts of δ′and θ′phases dispersed in the matrix during the whole deformation. DRX was easier to develop and had dominated the dynamic softening at the same strain of 0.4 at 500 °C. The pinning effect of precipitation was not sensitive to the strain but to the temperature. The number of precipitations significantly decreased at 500 °C where only a few δ′phases remained. Consequently, the pinning effect of precipitations was weakened, while the driven force for the migration of dislocation and grain boundary increased. Thereby, more sufficient DRX could be activated at a smaller strain, and a significant growth of DRX grains at the large strain was present at 500 °C. The results in this article enable to provide useful guides for further developing the hot forming technology of 2195 Al–Li alloy.

Microstructure and superplasticity of Mg–2Gd–xZn alloys processed by equal channel angular pressing

Abstract Microstructure, mechanical properties and superplastic behavior of Mg–2Gd–xZn (x = 0, 1, 2 and 3 wt%) alloys were investigated after extrusion and equal channel angular pressing (ECAP). After only 2 passes of ECAP, a homogenous fine-grained microstructure with a grain size of 2.33 μm and a high fraction of high-angle grain boundaries of 84% were formed in the Mg–2Gd–3Zn (GZ23) alloy, while 4 ECAP passes were necessary to create such a structure in the other alloys. This was attributed to the higher solute drag effect in the other alloys, retarding dynamic recrystallization (DRX). Although DRX occurred more easily in the GZ23 alloy, the final DRX grain size was slightly coarser compared to the other alloys. Shear punch testing (SPT) showed that grain refinement during ECAP leads to a slight increase in the shear yield strength of all studied materials after 2 ECAP passes, which was mostly balanced by texture softening caused by the shear texture component and grain growth after 4 ECAP passes. Contrary to the other alloys, the GZ23 alloy exhibited superplastic behavior after a lower number of ECAP passes. In addition, the superplastic temperature for GZ23 was 648 K, which was lower than the 673 K observed for the other alloys. The m-values of ~0.45–0.5 and activation energies of 98–114 kJ/mol suggested grain boundary sliding (GBS) controlled by grain boundary diffusion as the dominant deformation mechanism in the superplastic regime. This was confirmed by microstructural observations.

The microstructure and mechanical properties of Mg-Gd-Y-Zn-Zr system and Mg-Gd-Y-Zr system alloys by RUE deformation

This study investigates the effects of long-period stacking order (LPSO) phases on the dynamic recrystallization (DRX) process. By comparing Mg-Gd-Y-Zn-Zr (GWZ) alloy and Mg-Gd-Y-Zr (GW) alloy deformed by 4 passes of Isothermal Reciprocating Upsetting-Extrusion (RUE), the initial alloy grain sizes are 113.4 μm and 88.2 μm, respectively, after 4 passes, the grain size becomes 3.5 μm and 4.8 μm, and the grain refinement of GWZ is greater. After 1 pass, the DRX volume fraction of GWZ alloy is 83% and 15%, which is related to the LPSO phases contained in the GWZ alloy. The texture strength of the GWZ alloy ranges from 8.5 of 1 pass to 2.2 of 4 passes, while the GW alloy is from 5.9 of 1 pass to 2.8 of 4 passes, mainly due to the DRX grain volume fraction. The tensile test results at room temperature (RT) showed that the ultimate tensile strength (UTS) and tensile yield strength (TYS) of GWZ alloy are higher than that of GW alloy, and the elongation is lower than that of GW alloy.

Dynamic recrystallization of a wrought magnesium alloy: Grain size and texture maps and their application for mechanical behavior predictions

Effect of dynamic recrystallization (DRX) on the grain refinement and texture modification was studied by conducting a series of hot compression on AZ31B Mg alloy. Processing-grain size-texture maps were established as a function of temperature, strain rate, strain, and the Zener-Hollomon parameter (Z). Moreover, influence of simultaneous changes in the grain size and texture on tensile yield strength and ductility of the hot-worked Mg alloy was studied using the grain size and texture maps established. The processing-grain size map showed that the DRX grain size decreased with the increase in Z, also revealing various characteristics ranging from a grain growth, grain refinement, to a bimodal distribution of ultrafine grains and partially recrystallized grains. The effect of twinning on the grain refinement was also evident at high Z conditions. The processing-texture map revealed that the initial fiber texture was altered significantly to a shear, off-normal, or extension-twin texture with the increase in Z. The Schmid-factor maps were calculated to identify a dominant deformation mode during a subsequent tensile deformation of the hot-worked samples. Finally, a corresponding Hall-Petch relationship for each dominant deformation mode was used to establish tensile yield-strength maps, which agree well with the measured data.

Orientation-Dependent Characteristics for Residual Grains during Hot Deformation of Nickel-Based Alloy 925

In the present work, the orientation characteristics of residual grains during hot deformation of an age-hardening Ni-Fe-Cr alloy (Alloy 925) at different conditions were systematically analyzed through high-resolution electron back-scatter diffraction. Based on the measurement of the kernel average misorientation, the density of geometrical necessary dislocations (GNDs) was further calculated. The orientation-dependent deformation mechanism of the residual grains was also discussed using Schmid factor difference ratio (SFDR) analysis. The results show that the deformed microstructure features typical “necklace” structures. Many distorted twin boundaries can be observed within the residual grains at 950 °C. When the deformation temperature increases to 1150 °C, the volume fraction of dynamic recrystallization (DRX) increases, leading to the extensive formation of primary Σ3 twin boundaries. Additionally, the GNDs are widely distributed in the residual grains, while they are rare for the recrystallized grains. The maximum GND density value can be obtained at the interface of “soft–hard” grains. The GND density also increases at higher strain rates, and the number of DRX grains significantly affects the distribution of the GND density. Moreover, based on the calculations and SFDR analysis, it can be summarized that the {100} and {111} grains are prone to deform in the uniserial slip mode and the multiple slip mode, respectively.

Modifying microstructures and tensile properties of Mg-Sm based alloy via extrusion ratio

Abstract Microstructure and tensile properties of a Mg-Sm-Zn-Zr alloy with various extrusion ratios (ERs) of 6.9, 10.4 and 17.6 were systematically investigated. It was identified that, greater ER increased dynamic recrystallization (DRX) fraction and coarsened DRX grains, which further suggests weakened basal fiber texture for the studied alloy. This is mainly due to the rising temperature from massive deformation heat when hot-extrusion. As a result, greater ER corresponds to a decreased strength but improved ductility. Finally, transmission electron microscopy (TEM) observations reveal that the dominant intermetallic phase, Mg3Sm, is metastable, and it will transform into Mg41Sm5 during extrusion with high-ER. This transformation leads to the accumulation of surplus Sm and Zn atoms, which induces the precipitation of SmZn3 phase at the surface of Mg41Sm5 matrix.

Microstructure and texture evolution of TB8 titanium alloys during hot compression

In this study, microstructure and texture evolution of TB8 titanium alloys during hot deformation were investigated by using electron back-scattered diffraction (EBSD) analysis. The results showed that dynamic recrystallization (DRX) behavior of TB8 titanium alloys was drastically sensitive to the strain. As the true strain raised from 0.2 to 0.8, the degree of DRX gradually increased. The nucleation mechanism of recrystallization was observed, including discontinuous dynamic recrystallization (DDRX) resulting from the bulging of original boundaries. Furthermore, continuous dynamic recrystallization (CDRX) occurred because of the transformation of low-angle grain boundaries (LAGBs) to high-angle grain boundaries (HAGBs) in the interior of the original deformed grains. The texture evolution of TB8 titanium alloy during hot deformation process was analyzed in detail, and five texture components were observed, including {001} $$\left\langle { 100} \right\rangle$$ , {011} $$\left\langle { 100} \right\rangle$$ , {112} $$\left\langle { 1 10} \right\rangle$$ , {111} $$\left\langle { 1 10} \right\rangle$$ , and {111} $$\left\langle { 1 1 2} \right\rangle$$ . As the true strain increased, deformation textures were gradually weakened due to an increase in the volume fraction of DRX grains. When the true strain was 0.8, the main texture components consisted of the recrystallization texture components of the {001} $$\left\langle { 100} \right\rangle$$ and {011} $$\left\langle { 100} \right\rangle$$ textures.

Microstructural evolution and superplastic behavior of a fine-grained Mg−Gd−Y−Ag alloy processed by simple shear extrusion

Abstract Two magnesium alloys with the nominal compositions of Mg−6Gd−3Y (GW63) and Mg−6Gd−3Y−1Ag (GW63−1Ag) were hot extruded and then processed by 6 passes of the simple shear extrusion (SSE) process at 553 K. Both SEM and EBSD studies confirmed the mean grain size reduction of the extruded base GW63 alloy from 10.1 to 2.9 μm by adding 1 wt% Ag. This decrease in the grain size was due to the formation of the Ag-containing precipitates with network-type morphology at the grain boundaries of the extruded GW63−1Ag alloy. Further grain refinement was achieved after SSE through the occurrence of DRX in both Ag-free and Ag-containing alloys. However, the GW63−1Ag alloy showed a higher fraction of DRX grains and HAGBs after SSE processing compared to the Ag-free alloy. The enhanced DRX behavior was attributed to the smaller initial grain size of the Ag-containing alloy in the as-extruded condition and the role of Ag addition in suppressing the solute drag effect of the segregated Gd and Y elements at the grain boundaries. The superplastic behavior of the alloys was assessed via the shear punch testing (SPT) method performed in the temperature ranges of 623–723 K for the extruded specimens and 573–673 K for the SSE processed alloys. It was revealed that none of the extruded alloys exhibited superplastic flow, because of their large grain sizes. The GW63 alloy processed by 6 passes of SSE displayed a maximum m-value of 0.38 at 648 K, while the high strain rate sensitivity (SRS) index of 0.5 was measured at 623 K for the Ag-containing alloy after SSE. This was accompanied with a superplastic deformation behavior of the latter alloy, for which an activation energy of 105 kJ mol−1 that is close to that of the grain boundary diffusion of pure Mg was obtained. Therefore, grain boundary sliding (GBS) associated with grain boundary diffusion was introduced as the dominant deformation mechanism during the superplastic flow of the Ag-containing alloy processed by SSE.

Influences of the Texture Characteristic and Interdendritic LPSO Phase Distribution on the Tensile Properties of Mg–Gd–Y–Zn–Zr Sheets Through Hot Rolling

The Mg–Gd–Y–Zn–Zr alloy sheets with different texture characteristics and distribution of the interdendritic long period-stacking ordered (LPSO) phases were fabricated through altering the final rolling reduction (FRR). The results showed that the texture characteristic was closely related to FRR and affected the tensile properties of the resulted sheets to some extent. The Schmid factor (SF) of the basal $$\left\langle a \right\rangle$$ slip improved with further FRR, which was ascribed to that the dynamic recrystallization (DRX) grains expand into the deformed grains with basal texture. However, the improvement of the tensile yield strength (TYS) with further FRR indicates that the strengthening effect from DRX grains surpasses the weakening effect from the elevated SF. The formation of the line-distributed interdendritic 14H-LPSO phases can also affect the tensile properties of the resulted sheets. The line-distributed interdendritic 14H-LPSO phases along rolling direction (RD) can act as reinforcing fiber and contribute to the higher TYS along RD and 45° to some extent, which resulted in the higher TYS along 45° compared with that along transverse direction (TD) for each resulted sheet under the circumstance of approximate basal $$\left\langle a \right\rangle$$ and pyramid $$\left\langle {c + a} \right\rangle$$ friction stress. Thus, the tensile yield strength is not only related to the texture, but also depends on the grain size and line-distributed interdendritic LPSO phases. The micro-cracks spread perpendicular to the tension direction, and thus, the larger cracks form within the line-distributed 14H-LPSO phases during tension along TD, which accounts for the lower fracture elongation along TD.