Thermal Spike Research Articles

Molecular dynamics simulating the effects of Shockley-type stacking faults on the radiation displacement cascades in 4H-SiC.

Four-layer hexagonal silicon carbide (4H-SiC) is a promising material for high-temperature and radiation-rich environments due to its excellent thermal conductivity and radiation resistance. However, real 4H-SiC crystals often contain Shockley-type stacking faults (SSF), which can affect their radiation resistance. This study employed molecular dynamics (MD) simulation method to explore the effects of SSF on radiation displacement cascades in 4H-SiC. We conducted a comprehensive study of various SSF within the crystalline framework of 4H-SiC, and analyzed their stacking fault energy (SFE). We simulated the radiation displacement cascade in 4H-SiC with SSF and analyzed the effects of SSF on the distribution of radiation displacement defects. We simulated the radiation displacement cascade in 4H-SiC with SSF under different energies of primary knock-on atom (E PKA) and temperatures (T) conditions, and analyzed the variation pattern of the number of radiation displacement defects and clusters. The results indicated that SSF limits defect distribution position. SSF has an effect on the defects and clusters of 4H-SiC in the displacement cascade, and SSF can affect the maximum working temperature of 4H-SiC.

Comparative study of collision cascades and resulting displacement damage in GaN, Si and Ge

Comparative study of collision cascades and resulting displacement damage in GaN, Si and Ge

Study on damage of Gd2O3-CeO2 under electronic energy loss: comparison between bulk-like and nanostructure.

To understand the physical phenomena responsible for radiation damage of the materials used in nuclear reactors, and thus study their operation life and/or efficiency, it is required to simulate the conditions by exposing the materials to energetic ions. Ceria (CeO2) has been proposed as one of the inert matrices for the transmutation of minor actinides in the futuristic inert matrix fuel (IMF) concept. The inert matrix should also contain burnable poison to compensate for the initial reactivity of fuel. In this context, gadolinium (Gd) is an excellent burnable poison with a high neutron absorption cross-section. In view of this, Gd2O3-CeO2 nano-powders were synthesized and sintered at 800 °C and 1300 °C to obtain different grain sizes and morphologies. FESEM and TEM were carried out to study the grain size of pristine pellets. The sintered pellets were irradiated with 80-MeV Ag ions (electronic energy loss (Se) regime) at room temperature to emulate the effect of fission fragments. For analysis of the effect of grain size on the irradiation-induced structural degradation at different fluences, GIXRD and Raman spectroscopy were performed. Significantly large damage has been observed for the smaller grain-sized samples (sintered at 800 °C) as compared to the large grain-sized sample (sintered at 1300 °C). Neither of the samples amorphized under the present experimental conditions as indicated by the presence of the Raman-active T2g mode (centred at 462 cm-1) and all the XRD peaks of fluorite cubic structure up to the highest fluence employed (1 × 1014 ions cm-2). X-ray photoelectron spectroscopy results demonstrate that Ce4+ to Ce3+ and vacancy-related isolated clusters are the main defects produced in the systems. The radiation tolerance behaviour of the samples is understood with the help of thermal spike simulation, which indicates higher transient lattice temperatures with longer duration in the smaller grain-sized sample upon irradiation. Gd-doped ceria thus possesses good radiation stability in the Se regime, indicating its potential for application in IMFs.

Unravelling the jerky glide of dislocations in body-centred cubic crystals.

In situ straining tests in high purity α-Fe thin foils at low temperatures1 have demonstrated that crystal line defects, called dislocations, have a jerky type of motion made of intermittent long jumps of several nanometres. This observation conflicts with the standard Peierls mechanism for plastic deformation in body-centred cubic crystals, where the screw dislocation jumps are limited by inter-reticular distances, that is, distances of a few angstroms. Employing atomic-scale simulations, we show that although the short jumps are initially more favourable, their realization requires the propagation of a kinked profile along the dislocation line, which yields coherent atomic vibrations acting as travelling thermal spikes. Such local heat bursts favour the thermally assisted nucleation of new kinks in the wake of primary ones. The accumulation of new kinks leads to long dislocation jumps like those observed experimentally. Our study constitutes an important step towards predictive atomic-scale theory for materials deformation.

Engineering NiO Thin Film Properties using Ag9+ Ion Irradiation at Various Fluences

The impact of the Ag9+ ion irradiation on the characteristics of nickel oxide (NiO) films with several ion fluences including 1 × 1012, 1 × 1013 and 1 × 1014 ions cm−2 has been studied. These films were deposited over fluorine-doped tin oxide (FTO) substrate via spin coating technique. After that, structural, optical, vibrational, and electrical characteristics of all films were investigated employing different techniques. The change in the structure due to Ag9+ ion has been studied by GIXRD technique. A slight improvement in crystalline nature of NiO thin film was observed at 1 × 1012 ions cm−2 ion fluence that can be understood via thermal spike model. A decrement in value of transmission has been observed in the case of all thin films with ion fluence of Ag9+ ion. In addition, it was also observed that samples exposed to Ag9+ ions resulted in reduced intensity of the 1LO and 2LO modes in Raman spectrum. The reduced intensity of the Raman modes indicates the increment in the lattice defects. Further, AFM analysis showed that increment in the ion fluences of incident Ag9+ on NiO thin films led to an enhancement in surface roughness. Moreover, the Hall effect measurements were also carried out to examine the electrical characteristics of NiO films. From this measurement, it was observed that the conductivity of NiO varies along with the Ag9+ ions fluence, and it appears that the variation in resistivity follows the change in band gap.

Simulation of proton-induced primary displacement damage in GaAs under different ambient temperatures

The performance of on-orbit GaAs-based solar cells is susceptible to the displacement damage effect. The proton-induced primary displacement damage in GaAs on a geosynchronous equatorial orbit (GEO) was simulated and analyzed by combining the Monte Carlo (MC) and molecular dynamics (MD) methods. The MC simulation provided the distribution of primary knock-on atoms (PKAs) in GaAs induced by GEO-related protons to the MD simulation. In MD simulations, the effects of radiation fluence and ambient temperature on the displacement damage were considered. The simulation results showed that GEO-related protons generated a significant number of PKAs within an energy range of below 10 keV in GaAs. The high-fluence radiation emulated by the binary PKA could generate more point defects and cluster defects in GaAs than the low-fluence radiation emulated by single PKAs. As compared to room temperature (300 K), both a low (100 K) and high (500 K) ambient temperature could deteriorate the displacement damage. In addition, a high ambient temperature of 500 K could induce widespread thermal spikes in GaAs as compared to 100 and 300 K. This work can provide useful insight into the proton-induced displacement damage in GaAs and the radiation hardening of GaAs-based photoelectric devices in space.

Simulation of displacement damage of InP induced by protons and α-particles in low Earth orbit

Indium phosphide (InP) material hasmany advantages, such as large band gap, high electron mobility, high photoelectric conversion efficiency, high temperature resistance, and radiation resistance, which is superior to silicon (Si) and gallium arsenide (GaAs). Meanwhile InP is widely used in optical communication, high-frequency millimeter waves, optoelectronic integrated circuits, satellite communication, space solar cells, and other fields. Radiation particles incident on InP device can generate displacement atoms inside the device through elastic processes. And these displacement atoms continue cascade collisions to generate lattice defects which are vacancies, interstitials, and clusters. These defects capture electrons-holes by defective energy levels in the energy band, and then resulting in a decrease in the life of minority carriers which is the reason of degradation of InP devices. The process of degradation of InP device, induced by lattice defects from ion-irradiation, is called displacement damage effect (DDE). The non-ionizing loss energy (NIEL) scaling is a useful method to predict the degradation of device caused by DDE of radiation particles. Many studies have shown that the NIEL is linearly related to the damage coefficient of InP device. Previous studies of radiation damage effect of InP device mainly focused on single-energy protons, electrons, and neutrons. Of the particles in low earth orbit (LEO),the vast majority of particles are protons, with a few being α particles and electrons, while the electron’s NIEL is too small and its DDE is negligible. The InP’s NIEL induced by proton and α energy in LEO has not been studied in detail. Therefore, this paper uses Monte Carlo software Geant4 to study the NIEL, damage energy distribution with depth, and annual total non-ionization loss energy generated by protons and α particles in LEO in 500/1000/5000 μm InP materials. The shielding of 150-μm-thick SiO<sub>2</sub> layer and 2.54-mm-thick Al layer from protons and α particles are used as InP solar cell and InP devices in spacecraft, respectively. It is found that the energy spectrum determines the non-ionizing damage energy <inline-formula><tex-math id="M1">\begin{document}$ {T}_{\text{dam}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="5-20231499_M1.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="5-20231499_M1.png"/></alternatives></inline-formula> distribution, and then influences the NIEL value: the NIEL value increases with <inline-formula><tex-math id="M2">\begin{document}$ {T}_{\text{dam}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="5-20231499_M2.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="5-20231499_M2.png"/></alternatives></inline-formula> increasing and thickness of InP material decreasing. And α NIEL is larger than proton’s, the single particle DDE of InP device, induced by α particles, should be concerned. The annual non-ionizing damage energy of proton accounts for 98%, which means that proton is the main factor degrading InP devices in LEO.

Effect of the sonic shock wave on void evolution in materials under irradiation

Understanding the void-cascade interaction is of great importance for clarifying the irradiation damage as a major challenge in nuclear industry, since it typically causes void annihilation or shrinkage, which greatly affects the swelling of irradiated materials. But the current understanding of it is extremely limited due to the neglect of the sonic shock wave. Herein, we take γ-U as the representative model due to the emergence of a violent sonic shock wave there. Molecular dynamics simulations are performed to explore the underlying mechanism of the sonic shock wave interacting with voids. It is firstly revealed that the sonic shock wave is essentially focusons along <111> crystal orientation family, attributed to the highest energy transfer efficiency along <111> in γ-U. These focusons can cause void annihilation or shrinkage via sliding, while thermal spikes only cause annihilation by covering voids. Combining these two factors, we propose a model to qualitatively epitomize the void-cascade interaction, in which the influence scope exhibits an intriguing anisotropic feature, overturning a long-accepted view that the void-cascade interaction is isotropic. This model is further generalized to other nuclear materials owing to the similar mechanism of the sonic shock wave. Moreover, we find distinct size effect of voids on void-cascade interaction. Thermal spikes hardly affect voids that are too large to be covered, while the sonic shock wave also causes visible shrinkage in large voids. The present work proves that the sonic shock wave has a non-negligible effect on void evolution, improving the fundamental understanding of void-cascade interaction in irradiated materials.

Hydrogen irradiation-driven computational surface chemistry of lithium oxide and hydroxide.

We have investigated, using molecular dynamics, the surface chemistry of hydrogen incident on the amorphous and crystalline lithium oxide and lithium hydroxide surfaces upon being slowed down by a collision cascade and retained in the amorphous surface of either Li2O or LiOH. We looked for the bonding of H to the resident structures in the surface to understand a possible chain of chemical reactions that can lead to surface transformation upon H atom impact. Our findings, using Density-Functional Theory (DFT) trained ReaxFF force field/electronegativity equalization method potentials, stress the importance of inclusion of polarization in the dynamics of a Li-O-H system, which is also illustrated by DFT energy minimization and quantum-classical molecular dynamics using tight binding DFT. The resulting polar-covalent chemistry of the studied systems is complex and very sensitive to the instantaneous positions of all atoms as well as the ratio of concentrations of various resident atoms in the surface.

Shock wave induced migration of an edge dislocation dipole in alpha-Fe

The mobility of a 1/2〈111〉{110} edge dipole in alpha-iron has been studied using molecular dynamics simulations. Collision cascades generated by keV recoils have been shown to induce the migration of dislocations. In order to elucidate the origin of the motion of these dislocations, and separate the production of defects from temperature or pressure effects, a stressed region of different shapes (sphere and cylinder) is simulated close to the edge dipole. We observe that the generated shock wave triggers the movement of the dislocations even when no defects are produced. The shape of the distorted region and the character of the dislocations influence the way the dislocations move, due to the change in Peach-Koehler force direction and to the fact that the shock waves arrive to the different parts of the dislocations at different times.

Thermal-plex: fluidic-free, rapid sequential multiplexed imaging with DNA-encoded thermal channels.

Multiplexed fluorescence imaging is typically limited to three- to five-plex on standard setups. Sequential imaging methods based on iterative labeling and imaging enable practical higher multiplexing, but generally require a complex fluidic setup with several rounds of slow buffer exchange (tens of minutes to an hour for each exchange step). We report the thermal-plex method, which removes complex and slow buffer exchange steps and provides fluidic-free, rapid sequential imaging. Thermal-plex uses simple DNA probes that are engineered to fluoresce sequentially when, and only when, activated with transient exposure to heating spikes at designated temperatures (thermal channels). Channel switching is fast (<30 s) and is achieved with a commercially available and affordable on-scope heating device. We demonstrate 15-plex RNA imaging (five thermal × three fluorescence channels) in fixed cells and retina tissues in less than 4 min, without using buffer exchange or fluidics. Thermal-plex introduces a new labeling method for efficient sequential multiplexed imaging.

Assessment of Thermal Runaway propagation in lithium-ion battery modules with different separator materials

The current work aims to understand and model thermal runaway (TR) events in lithium-ion (LIB) 18650 cells within the context of aircraft battery applications. The primary goal is to comprehend the phenomenon and discuss strategies for mitigating its consequences during aircraft operation. TR is modeled using Arrhenius kinetic equations and is implemented in both lumped parameters (Matlab SimulinkTM), and 3D CFD simulations (Ansys FluentTM) using User Defined Functions. To validate the thermochemical model, cells are initially simulated in an oven test, where a cell is exposed to a temperature-controlled atmosphere, triggering exothermic reactions. With a strong correlation between lumped parameters and 3D models, the latter is simulated under battery module installation conditions. An internal short-circuit is then implemented within the cell to observe how thermal runaway is triggered by an internal heat source. The trigger cell is subsequently placed in a battery module assembly to assess the dominant heat transfer modes and the likelihood of TR induction from one cell to its neighbors. This work’s main objective and innovation are to compare different materials in which cells are immersed while observing the main heat transfer parameters for each material. Three conditions are tested: ceramic paper fiber and G7 as solid separators, and no separator material, where air fills the gaps between cells. The analysis of heat transfer modes reveals radiation’s dominance in the case of air interstice, suggesting the possibility of using a special coating to reduce the cell surface emissivity as an alternative to decrease the likelihood of TR propagation. Thus, two values of surface emissivity were tested in the case of air. Considering a cell triggered by an internal short-circuit, a thermal runaway temperature spike is not observed in any of the four cases. However, the air interstice case with regular emissivity is the most critical one, with the closest cell reaching peak temperatures as high as 136 °C in 490 s. The ceramic paper fiber is considered the best separator material, as it postpones the temperature increase in the closest cell while also being lighter than G7. The results and discussions concerning heat propagation presented herein can serve as guidelines for developing strategies to mitigate thermal runaway in battery modules.

Influence of irradiation-induced point defects on nanotribological properties of m-plane GaN investigated using molecular dynamics simulation

Molecular dynamics (MD) simulation toward the irradiation cascade collision of GaN (10−10) by using different primary knock-on atom (PKA) energies was performed. Simulation results showed that point defects comprising vacancies and interstitials in pairs increased with increased PKA energy. The number of stable defects after cascade collision was linearly related to the PKA energy, which well agreed with the Norgett–Robinson–Torrens equation. Then, we investigated the effect of irradiation-induced point defects on the nanotribological properties and subsurface damage of the GaN (10−10) workpiece by MD simulation of nanoscratching. The irradiation-induced point defects induced a significant change in the wear morphology, as well as more slight wear and a lower coefficient of friction, compared with non-irradiated GaN. The irradiated GaN also exhibited fewer chips and smoother surfaces than the non-irradiated one after scratching. The number of deformed atoms of GaN increased with increased PKA energy, suggesting that irradiation can suppress the atomic/near-atomic scale deformation of GaN crystal under certain conditions. The presence of point defects can, to some extent, hinder the development of dislocations and differentiate the scratching-induced subsurface damage. This study provided atomic-scale insight into the effect of irradiation point defects on the nanotribological behavior of GaN.

Molecular dynamics simulation of primary irradiation damage in Ti-6Al-4V alloys

Displacement cascade behaviors of Ti-6Al-4V alloys are investigated using molecular dynamics (MD) simulation. The embedded atom method (EAM) potential including Ti, Al and V elements is modified by adding Ziegler-Biersack-Littmark (ZBL) potential to describe the short-range interaction among different atoms. The time evolution of displacement cascades at the atomic scale is quantitatively evaluated with the energy of primary knock-on atom (PKA) ranging from 0.5 keV to 15 keV, and that for pure Ti is also computed as a comparison. The effects of temperature and incident direction of PKA are studied in detail. The results show that the temperature reduces the number of surviving Frenkel pairs (FPs), and the incident direction of PKA shows little correlation with them. Furthermore, the increasing temperature promotes the point defects to form clusters but reduces the number of defects due to the accelerated recombination of vacancies and interstitial atoms at relatively high temperature. The cluster fractions of interstitials and vacancies both increase with the PKA energy, whereas the increase of interstitial cluster is slightly larger due to their higher mobility. Compared to pure Ti, the presence of Al and V is beneficial to the formation of interstitial clusters and indirectly hinders the production of vacancy clusters.

Molecular Dynamics Simulations of Displacement Cascades in BCC-Fe: Effects of Dislocation, Dislocation Loop and Grain Boundary

The interactions between displacement cascades and three types of structures, dislocations, dislocation loops and grain boundaries, in BCC-Fe are investigated through molecular dynamics simulations. Wigner–Seitz analysis is used to calculate the number of point defects induced in order to illustrate the effects of three special structures on the displacement cascade. The displacement cascades in systems interacting with all three types of structure tend to generate more total defects compared to bulk Fe. The surviving number of point defects in the grain boundary case is the largest of the three types of structures. The changes in the atomic structures of dislocations, dislocation loops and grain boundaries after displacement cascades are analyzed to understand how irradiation damage affects them. These results could reveal irradiation damage at the microscale. Varied defect production numbers and efficiencies are investigated, which could be used as the input parameters for higher scale simulation.

A steady-state irradiation creep and thermal creep model for zirconium alloys

In this work, a mechanistic steady-state creep model is developed to characterize the macroscopic strain rate of metallic materials affected by irradiation flux, testing temperature and applied stress. Thereinto, the steady-state strain rate is obtained by considering the density evolution of mobile dislocations, which involve the mechanisms of dislocation multiplication, dynamic annihilation and time-dependent dislocation annihilation. In order to effectively analyze the irradiation creep behavior in the low and high stress region, main attentions are focused on the influence of dislocation mobility on the process of time-dependent dislocation annihilation. At low stress, dislocation mobility is affected by dislocation climb and thermally activated glide. For the former, the absorption of irradiation-induced point defects can promote dislocation climb; whereas, thermally activated dislocation glide might be inhibited by the existing defect clusters. At high stress, the dominant deformation mechanism changes from dislocation climb to displacement cascade unpinning. For the latter, an explicit formula for dislocation mobility is deduced to address the influence of dislocation unpinning from the barriers on irradiation creep. To further verify the established model, thermal creep and irradiation creep data of zirconium alloys are considered to compare with the theoretical results. A good agreement is achieved over a wide range of temperature and stress indicating that the model can well describe the deformation behavior of steady-state creep. In addition, contribution of the dominant dislocation mobility components and dislocation density evolution components is compared under both thermal and irradiation creep, which can facilitate the comprehension of fundamental creep mechanisms of metallic materials.

Transplantation and optimization of molecular dynamics simulation on MT-3000

Molecular dynamics (MD) simulation is a research method to simulate the change of particle systems with the help of the powerful calculating power of computers. As the number of atoms increases and the duration of the simulation system extends, current mainstream software for MD simulations has become increasingly strained. This is largely due to a surge in computing time, attributed to the architecture characteristics of the central processing unit (CPU), which executes instructions serially and accesses shared memory randomly. These features have resulted in an enormous overhead that these software applications can no longer efficiently manage. Recently, National University of Defense Technology proposed the MT-3000 processor, a multi-zone heterogeneous architecture with a double-precision peak performance of 11.5 TFLOPS. In this paper, we implement the heterogeneous transplantation and optimization of the massively parallel program for MD simulation on Tianhe new-generation supercomputer based on MT-3000. By porting the key computing hotspot module to the acceleration zones of MT-3000, we have greatly improved the efficiency and performance of the simulation of billion-metal-atom cascade collision. The experimental results show that the heterogeneous MD program on a single node can achieve about 6 times faster than the original version executed in a general purpose zone of MT-3000. On the basis of 250 thousand cores, the strong-scalability parallel efficiency of heterogeneous MD program using 4 million cores can reach 89.89%, and the weak-scalability parallel efficiency can reach 91.98%. It can be predicted that the heterogeneous MD implementation has excellent scaling ability to simulate large-scale atomic cascade collisions on ten million of cores.

Damage mechanism and mechanical properties of carbon nanotubes induced by He2+ ion irradiation: Molecular dynamics simulations and experiments

Carbon nanotubes (CNTs) are expected to play a pivotal role in future space device applications owing to their exceptional material properties. To ensure the reliability and safety of CNTs in such applications, meticulous assessment and understanding of their structural integrity under ions irradiation is imperative. In this study, the mechanisms of damage to 1–5 wall CNTs caused by the irradiation of He2+ ions in the 1–100 keV energy range were investigated by conducting molecular dynamics (MD) simulations. The mechanisms of damage induced by He2+ ion irradiation exhibited notable distinctions between single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs). SWCNTs easily conducted the kinetic energy of the He2+ irradiation out of the CNTs with cascade collisions, thereby reducing the damage they incurred, whereas the interlayer structure of the MWCNTs resulted in the irradiation energy being confined inside the tubes, leading to an increase in defects. The MD simulations revealed the irradiation swelling phenomenon of the MWCNTs in relation to the kinetic energy of irradiation and the cumulative fluence and indicated that swelling occurred simultaneously inward and outward along the radial direction of the CNTs. Irradiation-induced swelling was observed in experiments involving vertical array carbon nanotubes (VACNTs) irradiated with 540 keV He2+ ions. The results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization, along with the Raman analysis, indicate that the damage observed in CNTs due to He2+ ion irradiation closely resembles the findings obtained through MD simulations. Both experimental and MD simulation studies demonstrated that increasing the dosage of He2+ ion irradiation increased the CNT defects, causing a transition from the ordered graphite structure to amorphous C. Additionally, the compressive mechanical properties and surface adhesion mechanics of the irradiated VACNTs were examined by performing nanoindentation experiments. The tensile mechanical properties of the irradiated CNTs were evaluated using MD simulations. The combined results indicated that high-energy, high-fluence ion irradiation degraded the mechanical properties of the CNTs. This study comprehensively investigated the mechanisms of damage to CNTs under He2+ ion irradiation and the subsequent impacts on the mechanical properties of the CNTs. The findings of this research provide essential insights for comprehending the irradiation responses of CNTs and for designing composite CNT materials with enhanced radiation resistance.

Interaction between basal edge/mixed dislocations and point defects in zirconium

Zirconium alloys are widely used in nuclear reactors. Due to frequent displacement cascade events under irradiation, a large number of point defects are generated in zirconium alloys. In this work, the interactions between edge/mixed dislocations and point defects (vacancies and SIAs (self-interstitial atoms)) are studied by molecular dynamics (MD) simulations. The simulation results indicate that vacancies are not absorbed by edge dislocations but by mixed dislocations. Compared with their weak pinning effect on edge dislocation motion, vacancies have an intermediate pinning effect on the motion of mixed dislocation. In contrast, SIAs are all absorbed by edge and mixed dislocations and have a strong pinning effect. Then, force equilibrium is established on point defects to explain the absorption of point defects. The attractive force between dislocations and point defects is calculated from the binding energy, and the friction force of point defects is calculated from the migration energy. We found that the friction force of vacancies on edge dislocations is larger than the attractive force, and thus the vacancies cannot be absorbed. For the other three cases, the attractive force is large enough to overcome the friction force, and the point defects are absorbed.

Electronic effects on radiation damage in α-iron: A molecular dynamics study

Iron (Fe)-based alloys, which have been widely used as structural materials in nuclear reactors, can significantly change their microstructure properties and macroscopic properties under high flux neutron irradiation during operation, thus, the problems associated with the safe operation of nuclear reactors have been put forward naturally. In this work, a molecular dynamics simulation approach combined with electronic effects is developed for investigating the primary radiation damage process in α-Fe. Specifically, the influence of electronic effects on the collision cascade in Fe is systematically evaluated based on two commonly used interatomic potentials for Fe. The simulation results reveal that both electronic stopping (ES) and electron–phonon coupling (EPC) can contribute to the decrease of the number of defects in the thermal spike phase. The application of ES reduces the number of residual defects after the cascade evolution, whereas EPC has a reverse effect. The introduction of electronic effects promotes the formation of the dispersive subcascade: ES significantly changes the geometry of the damaged region in the thermal spike phase, whereas EPC mainly reduces the extent of the damaged region. Furthermore, the incorporation of electronic effects effectively mitigates discrepancies in simulation outcomes when using different interatomic potentials.