Recrystallization Of Alloy Research Articles

Study of the boundary migration of recrystallized grains under inhomogeneous deformation field by crystal plasticity – phase field simulation

ABSTRACT In this study, a grain boundary (GB) migration model based on crystal plasticity (CP) and phase field (PF) was constructed for recrystallization of magnesium alloys. The model introduced the stored energy field obtained by CP into the PF simulations, aiming to analyze the effect of the inhomogeneous stored energy generated under the plastic deformation on the GB migration. It was found that the curvature plays a more significant role in the inhomogeneous stored energy field than in the uniform deformation field. Although grains with hard orientation have a lower deformation storage energy, they are still partially swallowed due to mutual influence between GBs near the triple junction. The high energies in the original GBs increase the migration rate at the triple junctions locally for a short period of time, but it is not enough to make a significant difference over extended periods at mesoscopic scales. The simulation results in this study are helpful in explaining the previous experimental observations.

Experimental Investigation and Crystal Plasticity Modelling of Dynamic Recrystallisation in Dual-Phase High Entropy Alloy During Hot Deformation

Experimental Investigation and Crystal Plasticity Modelling of Dynamic Recrystallisation in Dual-Phase High Entropy Alloy During Hot Deformation

Recrystallization and stress evolution in Alloy 718

An extensive plasticity model base useful to predict stresses in thermo-mechanical processes where the microstructure changes has been established. The densities of mobile and immobile dislocations are the basic ingredients in the model. The motion of the former corresponds to plastic strain rate. The interaction between moving dislocations and various obstacles contributes to the material resistance. The focus is on the developed recrystallization model that is based on dislocation densities. The results show that recrystallization at high strain rates leads to a large number of nuclei that grow after the test. This means that most of the recrystallization occurs after the test.

The effect of Mg17Al12 intermetallic compound on dynamic recrystallization of cast-forged AZ80 magnesium alloy

The effect of Mg17Al12 intermetallic compound on dynamic recrystallization of cast-forged AZ80 magnesium alloy

Effect of Electric Pulse‐Assisted Extrusion on the Dynamic Recrystallization and Mechanical Properties of AZ31 Alloy

AZ31 Mg alloy with homogeneous refined microstructure and exceptional mechanical properties is obtained by electric pulse‐assisted extrusion in this article. The effect of the electric pulse on the recrystallization behavior of AZ31 alloy extruded at 423K is studied. The results show the recrystallization degree increases with increasing the current density, frequency, and pulse duration, respectively. Compared to the conventional extrusion samples at the same temperature, 423K, the DRX degree of the EPAE‐3 sample is increased from 11.3% to 80%, the corresponding yield strength, ultimate tensile strength, and tensile elongation to falur are improved from 322 MPa, 375 MPa, and 11.5% to 338 MPa, 404 MPa, and 16.8%, respectively. The dynamic recrystallization (DRX) and grain refinement mechanism of the electric pulse‐assisted extrusion is discussed, and the athermal effect of the electric pulse is considered to play a dominant role by increasing the nucleation rate and the vacancy diffusion flux.

The influences of microstructural length scale on the tensile properties and deformation mechanisms of Sn-3.0Ag-0.5Cu solder alloys

The influences of microstructural length scale on the tensile properties and deformation mechanisms of Sn-3.0Ag-0.5Cu solder alloys

Grain boundary migration hysteresis during recrystallization of IN738LC alloy fabricated via laser powder bed fusion

Grain boundary migration hysteresis during recrystallization of IN738LC alloy fabricated via laser powder bed fusion

Microstructural evolution and hot tensile deformation behaviors below δ-solvus temperature of IN718 alloy fabricated by plasma arc additive manufacturing

Microstructural evolution and hot tensile deformation behaviors below δ-solvus temperature of IN718 alloy fabricated by plasma arc additive manufacturing

The effect of multi-field coupling on dynamic recrystallization behavior in IN718 alloy

The dynamic recrystallization behavior of IN718 alloy is studied under multi-field coupling based on deformation difficulty at high temperature. The results show that dynamic recrystallization of IN718 alloy occur at 750°C under multi-field. At the same temperature, the resistance of IN718 alloy decreases and the degree of dynamic recrystallization increases with the increase of pulse current frequency. The dynamic recrystallization mechanism of alloy under multi-field coupling is discontinuous mechanism of grain boundary arch nucleation. The dynamic recrystallization ability is significantly improved under the action of multi-field coupling, thus the deformation resistance is reduced. The reason is that the dislocation movement intensifies under the action of multi-field coupling, which promotes dislocation proliferation and recovery, and then promotes dynamic recrystallization.

Effect of heat treatment on the microstructural evolution and mechanical property of nickel-based superalloy K447A manufactured by Powder Bed Fusion Laser Beam (PBF-LB)

Effect of heat treatment on the microstructural evolution and mechanical property of nickel-based superalloy K447A manufactured by Powder Bed Fusion Laser Beam (PBF-LB)

Static recrystallization behavior of biomedical Co-29Cr-6Mo-0.16 N alloy with negative stacking fault energy

Static recrystallization behavior of biomedical Co-29Cr-6Mo-0.16 N alloy with negative stacking fault energy

Role of (Al, Ti) alloying and annealing temperature in precipitation, recrystallization, and mechanical properties of ferrous multi-component alloys

Role of (Al, Ti) alloying and annealing temperature in precipitation, recrystallization, and mechanical properties of ferrous multi-component alloys

Effect of Precipitates on Dynamic Recrystallization and Texture of Mg-Sn Alloy Under Different Strain Rates

Effect of Precipitates on Dynamic Recrystallization and Texture of Mg-Sn Alloy Under Different Strain Rates

Effect of microalloying with rare-earth lanthanum on dynamic recrystallization behavior and mechanical properties of Ti sheets

Effect of microalloying with rare-earth lanthanum on dynamic recrystallization behavior and mechanical properties of Ti sheets

The extrusion ratios modification of Mg-2Gd-xMn alloys to exploration of the strengthening mechanisms

The extrusion ratios modification of Mg-2Gd-xMn alloys to exploration of the strengthening mechanisms

A physically based constitutive model considering dynamic recrystallization of ERNiCrMo-3 alloy

ERNiCrMo-3 alloy is widely used in the welding of nickel-based alloys. This study investigated the hot deformation and discontinuous dynamic recrystallization (DRX) behavior of ERNiCrMo-3 alloy through hot compression tests at deformation temperatures ranging from 990 °C to 1170 °C and strain rates ranging from 0.01 to 10 s−1. Experimental results showed that under conditions of elevated temperatures and lower strain rates, discontinuous dynamic recrystallization was prone to occur upon reaching critical strain, and the distribution of carbide and nitride particles within the alloy matrix affects recrystallization nucleation and grain boundary migration. A two-stage constitutive model was established based on classical dislocation density theory and DRX kinetics. Comparison between predicted and experimental data demonstrated a strong agreement, highlighting the accuracy and utility of the proposed constitutive model.

Effect of Cu on the Precipitation of α-Al(Mn,Cr)Si Dispersoids in an Al-Mg-Si-Mn-Cr Alloy

Nanoscale dispersoids will retard or inhibit recrystallization of aluminum alloys during thermomechanical processes. In the present study, the influence of an addition of 0.6 wt. % Cu on the precipitation behavior of dispersoids in an Al-Mg-Si-Mn-Cr alloy had been investigated. Large amounts of dispersoids with different shapes, e.g. cubic, rod-like and plate-like, were achieved in the experimental alloys after homogenization. Compared with the Cu-free alloy, Cu-added alloy exhibits a higher proportion of cubic shape dispersoid. HRTEM results indicated that the cubic shape dispersoid has an icosahedral quasicrystal structure, while the rod-like or plate-like shape dispersoids show a simple cubic crystal structure. Due to the presence of a high number density of quasicrystalline dispersoids, the Cu-added alloy exhibits a higher recrystallization resistance during hot compression. This study presents a new insight that besides the precipitation strengthening, the Cu alloying in an Al-Mg-Si-Mn-Cr alloy can also contributes to the precipitation of dispersoids.

Simulating the kinetics of recrystallization in Aluminum alloys

This contribution presents a brief overview of the simulation of recrystallization kinetics in metals. The study focuses on the annealing phenomena in a single-phase 1050 aluminum alloy of technical purity. To reveal the true nature of recrystallization, the kinetics is discussed by the well-establishes Johnson–Mehl–Avrami–Kolmogorov (JMAK) approach, while the constants of this model are related to the energy stored during deformation, nucleation rate, velocity of grain boundary, and grain boundary energy. The listed physical quantities are derived from different models, while the performance of the combined approach was tested for the cases where the diversity of driving forces for recrystallization was ensured by different straining levels. The softening of the material during annealing was evaluated by the microhardness. It was shown that the kinetics of recrystallization is strongly influenced by the stored energy and the process can be simulated by employing the JMAK equation.

In situ measurement of austenite grain growth and recrystallization using laser ultrasonics

The development of next generation process models and advanced high-strength steel products for thin slab casting and direct rolling requires quantification of microstructure evolution during thermomechanical processing. Laser ultrasonics is a non-contact in-situ method to record grain growth, recrystallization and phase transformations in metals and alloys. Here, we will present an improved experimental design that facilitates a continuous microstructure measurement through the various stages of simulated hot rolling from reheating to runout table cooling using a Gleeble thermomechanical simulator equipped with a laser ultrasonics for metallurgy (LUMet) system. Austenite grain growth and static recrystallization after hot deformation are quantified based on attenuation of the ultrasound waves whereas austenite decomposition can be recorded with the changes in ultrasound velocity during the phase transformation. Further, the LUMet results for a microalloyed low carbon steel are validated with conventional techniques including optical and electron microscopy as well as double-hit tests. These experimental studies demonstrate the capabilities of laser ultrasonics in the identification of both normal and abnormal grain growth, non-recrystallization temperature, recrystallization, and austenite decomposition kinetics in a single test for a given processing path, as well as its potential for accelerated optimization of process control under industrial rolling conditions.

Discontinuous dynamic recrystallization of TiNb alloys: Experiment and cellular automaton simulation

Discontinuous dynamic recrystallization of TiNb alloys: Experiment and cellular automaton simulation