Diffusion Of Atoms Research Articles

Study on dynamic behavior of atomic diffusion at interface between TiAlN coating and WC matrix

The molecular dynamics method was used to simulate the dynamic behavior change of atomic diffusion at interface between TiAlN coating and WC matrix in the carbide tool with TiAlN coating. It was determined that the one-way diffusion of C atom to TiAlN coating resulted in serious lattice distortion on the surface. Meanwhile, the whole diffusion process was accompanied by the continuous increase of stress, resulting in gradual deformation of the material. The interface bonding performance also decreases. Then, the surface energy and atomic layer convergence are calculated by the first-principles method. The TiAlN crystal surface is stable at 8 atomic layers, and the WC crystal surface is stable at 6 atomic layers, and then a stable microinterface model can be built. The relaxation processing for the established model was performed to determine the diffusion path of C atom. Then, the energy barrier, adhesion work, interface energy and fracture toughness of different transition state structures in the diffusion path of C atom are calculated, and it is determined that with the deepening of the diffusion of C atom in the coating, the binding ability of the interface of the coating base and the performance of the coating tool are more and more serious damage. Finally, the cutting experiment of TiAlN coated tool is designed. According to the surface topography of TiAlN coated tool in different periods, the simulation and theoretical analysis mentioned above are verified, which provides a theoretical basis for the subsequent research on improving the performance of coated tool.

Intermittent cluster dynamics and temporal fractional diffusion in a bulk metallic glass

Glassy solids evolve towards lower-energy structural states by physical aging. This can be characterized by structural relaxation times, the assessment of which is essential for understanding the glass’ time-dependent property changes. Conducted over short times, a continuous increase of relaxation times with time is seen, suggesting a time-dependent dissipative transport mechanism. By focusing on micro-structural rearrangements at the atomic-scale, we demonstrate the emergence of sub-diffusive anomalous transport and therefore temporal fractional diffusion in a metallic glass, which we track via coherent x-ray scattering conducted over more than 300,000 s. At the longest probed decorrelation times, a transition from classical stretched exponential to a power-law behavior occurs, which in concert with atomistic simulations reveals collective and intermittent atomic motion. Our observations give a physical basis for classical stretched exponential relaxation behavior, uncover a new power-law governed collective transport regime for metallic glasses at long and practically relevant time-scales, and demonstrate a rich and highly non-monotonous aging response in a glassy solid, thereby challenging the common framework of homogeneous aging and atomic scale diffusion.

Circular Economy Opportunity Utilizing Fitness for Service Methodology for Aged HIC Defected Reboiler

The phenomenon of Hydrogen-Induced Cracking (HIC) is a cracking mechanism of carbon steel material as in ASME SA- 516 pressure containing equipment operating in a wet sour H2S environment. Such phenomenon is mainly driven by the diffusion of hydrogen atoms into the carbon steel due to corrosion reaction. The Structural integrity of an in-service equipment that contain a flaw or damage such as HIC could be scrutinised using Fitness For Service (FFS) assessments as quantitative engineering evaluations. The assessments are conducted using methodologies specifically prepared for pressurized equipment. These assessments provide standard procedure that can be used to determine if pressurized equipment containing flaws could continue to operate safely for certain period of time. FFS assessments are recognized and referenced by the API Codes and Standards such as API- 510, 570, & 653, and by National Board-23. Those assessments are considered suitable methodologies for evaluating the structural integrity of pressurized equipment as heat exchangers, pressure vessels, piping systems and storage tanks where inspection has revealed degradation and flaws in the equipment. The objective of this paper isto illustrate API-579 case study of HIC of fifty (50) years operating pressurized equipment, namely reboiler.

Enhanced precision lapping techniques for fused quartz optical elements: Synergistic integration of mechanical and mechanochemical processes

Fused silica is a material of great importance in the field of precision optical equipment due to its excellent optical properties, e.g. photolithography, laser fusion devices, etc. However, the material's inherent hardness and brittleness render it a challenging material to process. Therefore, an enhanced precision lapping technique was proposed, i.e., a synergistic integration of mechanical and mechanochemical lapping processes. Firstly, a synergistic lapping tool with an outer layer of porous diamond abrasive and an inner layer of CeO2 abrasive was fabricated by hot press forming method. The reduction of layer thickness due to abrasion and detachment of the porous diamond abrasive layer was analyzed, and the lapping mechanism of porous diamond on fused silica materials was revealed. The surface creation mechanism of the CeO2 abrasive layer on fused silica material was analyzed by molecular dynamics simulation and the results were validated by enhanced precision lapping experiment. The results demonstrated that the surface atoms of fused silica are removed in a ‘remote disordered’ manner by conventional diamond abrasive grains, whereas the surface atoms of fused silica are removed in a ‘proximally ordered’ manner by the fine porous diamond abrasive grains through the micro-multi-flute cutting. Consequently, the grinding of a porous diamond abrasive layer can significantly reduce the processing damage, with the surface roughness of the lapping Ra reaching 199 nm. The lapping of CeO2 induces the formation of an oxygen bridge on the surface of fused silica, which then produces bending vibration. This is followed by the adsorption and diffusion of oxygen atoms, which form the -Ce-O-Si intermediate with the oxygen atoms shared with the fused silica. This process results in the formation of CeSiO3 and CaSiO3 compounds. The final surface quality with a surface roughness of Ra 21 nm was obtained by mechanochemical lapping of the cerium oxide abrasive layer. The single mechanical-mechanochemical composite ultra-precision lapping process provides technical support for the efficient and low-damage processing of hard and brittle components.

Study on interface diffusion and welding strength of Cu/Sn dissimilar metal electromagnetic pulse welding based on molecular dynamics simulation

The electromagnetic pulse welding (EMPW) method stands out for its rapid welding time, superior precision, and high automation, making it ideal for materials with significant melting point differences, specifically copper and tin, which often struggle to form robust joints. Utilizing molecular dynamics simulations, this study aims to investigate the interface evolution patterns under varying collision velocities and assess the welding strength of joints subjected to distinct tangential velocities. The findings reveal a profound correlation between the diffusion coefficient, system temperature, and the collision velocity during the simulated EMPW vertical collision. Specifically, at a collision velocity of Vz = 500 m/s, the interface tends to be linear, suggesting an unstable bonding state. However, when the collision velocity exceeds 700 m/s, a more intense diffusion of copper and tin atoms is observed, resulting in a wavy interface indicative of enhanced bonding capabilities. Furthermore, the study examines the shear behavior of welded joints subjected to oblique collisions with varying tangential velocities. The analysis reveals a transition in fracture locations from the joint-joint interface to the joint-base material interface and ultimately to the base material itself, as the tangential velocity increases from 50 m/s to 100 m/s and surpasses 200 m/s. This comprehensive evaluation of EMPW process variables provides a theoretical foundation for optimizing the mechanical properties of copper-tin EMPW joints.

Effect of the cooling behavior on phase transformation and mechanical property of RAFM steel

The phase transition behavior of RAFM steel during Hot Isostatic Pressing (HIP) diffusion bonding process would extensively impact the service performance of blanket component in the future fusion reactor. In this paper, the influence of cooling behavior on phase transformation and mechanical property of RAFM steel was studied using a combination of Electron Backscatter Diffraction (EBSD) and a thermal dilatometer. The results show that as the cooling rate decreases after austenitizing, the phase category transitions from a single-phase of martensite to the dual-phase of martensite and ferrite, along with an increase in the rate of ferrite, minor martensite packets and high-angle grain boundaries (HAGB). As the cooling rate decreases, the initial temperature for martensite transformation significantly increases, and the transformation driving force slowdown. Moreover, specimens processed with HIP cooling show lower strength, higher elongation, and a greater standard deviation of hardness compared to air cooling. These differences can be attributed to the formation of ferrite and the diffusion of carbon atoms within martensite. The research findings reveal the phase transition and microstructural evolution of martensite under varying cooling conditions, providing a reference for the controlling the cooling process after HIP bonding of blanket steel components in the future fusion reactor.

Microstructure, mechanical performance, thermal stability, and oxidation resistance of AlCrN/AlCrBN nano-multilayer coating

This study synthesized three different coatings using multi-arc ion coating technology: AlCrN, AlCrBN monolayer, and AlCrN/AlCrBN nano-multilayer coatings. A comparative investigation was conducted on the microstructure, mechanical performance, thermal stability, and oxidation properties of coatings. The results indicate the AlCrN, AlCrBN, and AlCrN/AlCrBN nano-multilayer coatings consist of face-centered cubic solid solution fcc-(Cr, Al)N phase. AlCrN/AlCrBN nano-multilayer coatings also exhibit better thermal stability and oxidation resistance than AlCrN and AlCrBN monolayer coatings. The AlCrN/AlCrBN nano-multilayer coatings have a dense, protective, Al2O3 layer formed during high-temperature oxidation. During high-temperature oxidation, the AM (amplitude modulation) decomposition of the AlCrN and AlCrBN monolayers in the AlCrN/AlCrBN nanolayers is inhibited by the structure of the multilayer coatings. The formation of dense oxides on the surface prevents the diffusion of Al and Cr atoms to the outside and prevents the diffusion of oxygen from the outside to the inside of the AlCrN/AlCrBN nanolayers.

High-performance MIM-type aluminum electrolytic capacitors with durable waterproof and wide temperature window

Capacitors are indispensable components of electronic circuits. Filter capacitors, mainly dominated by electrolytic capacitors, are critical for the accurate power supply of integrated circuits for central processors and storage devices, affecting the performance of advanced and sophisticated electronic equipment. However, electrolytic capacitors are restricted in working temperatures (<150 °C) and humidity conditions due to the inherent characteristics of MnO2 or polymer cathodes that tend to deteriorate at high temperatures and moisture. Here, high temperature resistant and conductivity SnO2 cathode and MIM-like (SnO2/AAO/Al) structures are introduced into aluminum electrolytic capacitors via ALD technology. First achieved in a higher temperature window (-60 °C∼330 °C), the capacitor maintains a stable capacity (114.5 ± 3.6 μF/cm2) and phase angles (-89.5 ± 0.2°) at 120 Hz. The tight stacking and conformability of ALD even allows unencapsulated devices to exhibit durable waterproof, showing stable performance for immersion in water within 90 days. Moreover, a thin amorphous Al2O3 (A) as buffer layer is introduced at electrode/dielectric interface, aiming to barrier the interfacial atomic diffusion at the SnO2/AAO. A stable vdW SnO2/A/AAO interfaces is obtained, proven by MD and DFT calculations. Impressively, the capacitor exhibits high reliability with high breakdown field strength (5.5 MV/cm), low leakage current (7.2 × 10–7 A/cm2 at 1 V) and low loss (2% at 120 Hz). Applied in circuits, the capacitor filters 100 kHz signal with a Vripple of only 15 mV and shows excellent charging and discharging behaviors. The work may pave the way for the practical application of electrolytic capacitors in harsh working environments.

Ubiquitous short-range order in multi-principal element alloys

Recent research in multi-principal element alloys (MPEAs) has increasingly focused on the role of short-range order (SRO) on material performance. However, the mechanisms of SRO formation and its precise control remain elusive, limiting the progress of SRO engineering. Here, leveraging advanced additive manufacturing techniques that produce samples with a wide range of cooling rates (up to 107 K s−1) and an enhanced semi-quantitative electron microscopy method, we characterize SRO in three CoCrNi-based face-centered-cubic (FCC) MPEAs. Surprisingly, irrespective of the processing and thermal treatment history, all samples exhibit similar levels of SRO. Atomistic simulations reveal that during solidification, prevalent local chemical order arises in the liquid-solid interface (solidification front) even under the extreme cooling rate of 1011 K s−1. This phenomenon stems from the swift atomic diffusion in the supercooled liquid, which matches or even surpasses the rate of solidification. Therefore, SRO is an inherent characteristic of most FCC MPEAs, insensitive to variations in cooling rates and even annealing treatments typically available in experiments.

Effect of quenching-super intercritical quenching-tempering process on the evolution of microstructure and the yield ratio of Ni–Cr–Mo steel

In the present study, X-ray diffraction, electron probe microanalysis, and transmission electron microscopy, among other advanced characterization methods, were used to analyze the microstructure and mechanical properties of the 9Ni steel treated at different heat treatment conditions. The goal was to reveal the dual-optimal strengthening mechanism of “low yield ratio and ultra-cryogenic toughness” of the investigated steel. The experimental results indicated that the 9Ni steel, designed with a ''Ni–Cr–Mo'' multi-elemental composition, balanced its hardenability and corrosion resistance. After the Q-Q' (710 °C) -T process, the diffusion of Cr and Mo atoms in the steel accelerated, while the Fe displacement diffusion formed a more stable FeNi face-centered cubic structure with a lattice energy of −76.98 eV. At this stage, the microstructure of the investigated steel primarily consisted of tempered sorbite (with an average effective grain size of 13.1 μm), tempered martensite lath clusters, reversed austenite, and precipitated Cr23C6 and Mo2C particles. This composition resulted in a low yield ratio. The concentration of Ni near the lath clusters promoted the formation of the reversed austenite with a volume fraction of 10.2%, ensuring the cryogenic toughness of the investigated steel.

Effect of ARB process on the plane stress fracture toughness, creep properties and forming limit diagram of Aluminum/BN/Copper composite strips

Abstract In the present study, Al/BN/Cu bimetal composite strips were fabricated via the accumulative roll bonding (ARB) process. Then, fracture toughness, mechanical properties, bonding strength, forming limit diagram (FLD), and creep properties have been studied via experimental techniques. The study of creep behavior and mechanical properties showed a formation of a 17 μm atomic diffusion layer at the interface during ARB under three creep loading conditions namely 35 MPa at 225 °C, 35 MPa at 275 °C, and 30 MPa at 225 °C. The tensile strength of samples improved to 144 MPa which was about 234% in comparison with the primary Al monolithic sample. It was observed by the SEM that the fracture types changed to shear kind after higher passes including prominent effects on the fracture morphology. FLD curve dropped severely after the first ARB pass and then began to enhance at higher passes. The fracture toughness value of 30 MPa m1/2 was achieved after ten ARB passes. An intermetallic composition was created near Al. The creep failure time did decline by 44% and the stress level decreased by 13% at a constant temperature. It can be concluded that applied temperature and stress effect on creep properties especially leads to increasing the slope of creep curves with higher stresses. This trend was opposite for the creep temperature at higher temperature levels. Moreover, dynamic recrystallization was observed through the crystalline structure of samples.

Determination of γ/γ' interface free energy for solid state precipitation in Ni-Al alloys from molecular dynamics simulation.

Interface free energy is a fundamental material parameter needed to predict the nucleation and growth of new phases. The high cost of experimentally determining this parameter makes it an ideal target for calculation through a physically informed simulation. Direct determination of interface free energy has many challenges, especially for solid-solid transformations. Indirect determination of the interface free energy from the nucleation data has been done in the case of solidification. However, a slow on molecular dynamics (MD) simulation time scale atomic diffusion makes this method not applicable to the case of nucleation from the solid phase when precipitate composition is different from that in matrix. To address this challenge, we outline the development of a new technique for determining the critical nucleus size from an MD simulation using a recently developed method to accelerate solid-state diffusion. The accuracy of our approach for the Ni-Al system for Ni3Al (γ') precipitates in a Ni-Al (γ) matrix is demonstrated well within experimental accuracy and greatly improves upon previous computational methods [Herrnring et al., Acta Mater. 215(8), 117053 (2021)].

Integrated model for simulating Coble creep deformation and void nucleation/growth in polycrystalline solids - Part I: Theoretical framework

This study proposes an integrated model for simulating Coble creep deformation and void nucleation/growth in a 3D polycrystalline solid. Part I of the paper provides a theoretical framework for the proposed model. A representative volume element approach is employed to predict the effects of 3D polycrystalline morphology. The model comprises two distinct but interconnected stages: deformation and void nucleation/growth. The deformation stage of the proposed model comprises two sub-models: grain boundary (GB) migration and GB diffusion. The void nucleation/growth stage is composed of three consecutive calculations: void nucleation, void growth, and postprocessing. The process simulated in the void nucleation/growth stage is driven by relative GB velocity of the respective GBFs and diffusional fluxes between adjacent GBFs, which are provided from the deformation stage. The void nucleation rate is quantified using the relative GB velocity, and the initial void size is determined based on the stability condition for void existence derived from Helmholtz free energy. The void growth rate is evaluated by the atomic diffusion on the GBF and the surface of each void.

Enhanced Electrical Properties and Stability in IGZO TFTs via Low-Temperature Activation with MgOx Layer.

We propose the introduction of a magnesium oxide (MgOx) layer to reduce the temperature required for the activation of indium gallium zinc oxide (IGZO) thin films. By incorporating the MgOx layer between the IGZO channel layer and the gate insulator layer, the required activation temperature is lowered from 300 to 200 °C while enhancing the electrical performance of the IGZO thin-film transistor (TFT). Specifically, the field effect mobility is improved from 6.40 to 16.12 cm2/(V s), the on/off current ratio is enhanced from 1.62 × 109 to 7.16 × 109, and subthreshold swing is enhanced from 0.48 to 0.46 V/decade. Furthermore, IGZO TFTs with the MgOx layer exhibit enhancements in threshold voltage (VTH) shift compared to TFTs without the MgOx layer under positive bias stress (VGS = 20 V and VDS = 0.1 V for 10,000 s) and negative bias stress (VGS = -20 V and VDS = 0.1 V for 10,000 s): the VTH shifts are decreased from 2.40 to 1.72 V and from 0.56 to 0.53 V, respectively. These enhancements are verified through various analyses and are attributed to the diffusion of Mg atoms into the IGZO front channel during the low-temperature activation process, which results in the formation of Mg-doped IGZO between the MgOx and IGZO channel layers.

Diffusion Barrier Performance of Ni-W Layer at Sn/Cu Interfacial Reaction.

As the integration of chips in 3D integrated circuits (ICs) increases and the size of micro-bumps reduces, issues with the reliability of service due to electromigration and thermomigration are becoming more prevalent. In the practical application of solder joints, an increase in the grain size of intermetallic compounds (IMCs) has been observed during the reflow process. This phenomenon results in an increased thickness of the IMC layer, accompanied by a proportional increase in the volume of the IMC layer within the joint. The brittle nature of IMC renders it susceptible to excessive growth in small-sized joints, which has the potential to negatively impact the reliability of the welded joint. It is therefore of the utmost importance to regulate the formation and growth of IMCs. The following paper presents the electrodeposition of a Ni-W layer on a Cu substrate, forming a barrier layer. Subsequently, the barrier properties between the Sn/Cu reactive couples were subjected to a comprehensive and systematic investigation. The study indicates that the Ni-W layer has the capacity to impede the diffusion of Sn atoms into Cu. Furthermore, the Ni-W layer is a viable diffusion barrier at the Sn/Cu interface. The "bright layer" Ni2WSn4 can be observed in all Ni-W coatings during the soldering reflow process, and its growth was almost linear. The structure of the Ni-W layer is such that it reduces the barrier properties that would otherwise be inherent to it. This is due to the "bright layer" Ni2WSn4 that covers the original Ni-W barrier layer. At a temperature of 300 °C for a duration of 600 s, the Ni-W barrier layer loses its blocking function. Once the "bright layer" Ni2WSn4 has completely covered the original Ni-W barrier layer, the diffusion activation energy for Sn diffusion into the Cu substrate side will be significantly reduced, particularly in areas where the distortion energy is concentrated due to electroplating tension. Both the "bright layer" Ni2WSn4 and Sn will grow rapidly, with the formation of Cu-Sn intermetallic compounds (IMCs). At temperatures of 250 °C, the growth of Ni3Sn4-based IMCs is controlled by grain boundaries. Conversely, the growth of the Ni2WSn4 layer (consumption of Ni-W layer) is influenced by a combination of grain boundary diffusion and bulk diffusion. At temperatures of 275 °C and 300 °C, the growth of Ni3Sn4-based IMCs and the Ni2WSn4 layer (consumption of Ni-W layer) are both controlled by grain boundaries. The findings of this study can inform the theoretical design of solder joints with barrier layers as well as the selection of Ni-W diffusion barrier layers for use in different soldering processes. This can, in turn, enhance the reliability of microelectronic devices, offering significant theoretical and practical value.

New numerical models of atomic diffusion in the atmospheres of cool Ap stars, including ambipolar diffusion of hydrogen

Ambipolar diffusion of hydrogen gives an additional upward thrust to metals that diffuse in the atmosphere of Ap stars. Its quantitative effect on the build-up of abundance stratification due to atomic diffusion that produces the observed abundance anomalies in Ap stars has not been evaluated so far. The purpose of this work is to quantify this effect throughout the stratification process of metals inside the atmosphere. We used our code caratmotion to compute the time-dependent atomic diffusion of four metals (Mg, Ca, Si, and Fe) in the atmosphere of a main-sequence star with an effective temperature of $8\,500$\,K, which is a typical temperature of Ap stars. The results, including ambipolar diffusion of H, are compared to results obtained without this process. Our main result is that ambipolar diffusion must be included in any calculation of atomic diffusion in Ap star atmospheres, at least for stars with $T_ eff 10\,000$\,K. We show that this concerns all metals, even those that are well supported by the radiation field, such as Fe. The crucial role of the stellar mass-loss rate is confirmed; it remains a determining parameter that is constrained, but still free in our calculations. We also present 3D calculations of Ca distributions in magnetic atmospheres. Questioning the interest of systematic searches for stationary solutions (which can often only be reached after a long evolutionary process), we note that remarkable behaviour can occur during the transient phases of the stratification build-up.

Effective strategies for improving the mechanical stability of aged Mg-Li alloys

To date, the aging softening of Mg-Li-Zn based alloys has been a critical issue limiting their industrial application. Here, we design a new Mg-Li alloy that exhibits exceptional mechanical stability after solution treatment and then water quenching by means of a hitherto unrecognized mechanism. The results indicate that precipitation of a semi-coherent MgLi2(ZnAg) phase leads to rapid age-hardening of the Mg-Li alloy after water quenching, as evidenced by the Ag atoms in the precipitate. A massive solid solution of Ag atoms in the β-Li phase strengthens the stability of the alloy and retards the diffusion of Li atoms from the β phase into the α matrix during aging. Zn atoms in the MgLi2Zn precipitate are replaced by Ag atoms which explain the origin of age-hardening and inhibit the evolution of the substable strengthened phase MgLi2Zn to the equilibrium softened phase MgLiZn. This research may contribute to the theoretical basis for solving the age-softening problem of Mg-Li alloys.

Effect of CeO2@Ni on the Oxidation Resistance of in Situ TiC/Ni Composite Applied for Intermediate Temperature Solid Oxide Fuel Cell Interconnects

The TiC/Ni composites with different CeO2 or CeO2@Ni content are fabricated by pressureless reactive sintering, and the CeO2@Ni particles are prepared by electroless plating technique. The results show that the continuous Ni layer is prepared on CeO2 particles, leading to the decrease of contact angle between CeO2 and Ni from about 116° to 65°. The relative density of composites with 1 wt% CeO2 increases from 85.79% to 96.45% by Ni layer on CeO2 particles. The CeO2 or CeO2@Ni particles exhibit no obvious influence on the microstructure of composites, and Ce atoms of CeO2 diffuse into TiC particles during the reactive sintering process. The mass gain of composite decreases from 7.4709 to 4.9075 mg cm−2 by addition of 1 wt% CeO2@Ni. The Ce‐doped in NiO and TiO2 would restrict the inward diffusion of O atoms and outward diffusion of Ni atoms, resulting in the improvement of oxidation resistance of composite. With the increase of CeO2@Ni content from 0 to 1 wt%, the surface specific resistance of composite decreases from 3.16 to 0.56 Ω cm2 at 800 °C due to the thinner oxide scale and lower bandgap of TiO2 by Ce doping.

Self-Diffusion of Ge in Amorphous Ge x Si1-x Films Studied In Situ by Neutron Reflectometry.

Ge x Si1-x alloys are gaining renewed interest for many applications in electronics and optics, especially for miniaturized devices showing quantum size effects. Point defects and atomic diffusion play a crucial role in miniaturized and metastable systems. In the present work, Ge self-diffusion in sputter deposited amorphous Ge x Si1-x alloys is studied in situ as a function of Ge content x = 0.13, 0.43, 0.8, and 1.0 by neutron reflectometry. The determined Ge self-diffusivities obey the Arrhenius law in the investigated temperature ranges. The higher the Ge content x, the higher the Ge self-diffusivity at the same temperature. The activation enthalpy decreases with x from 4.4 eV for self-diffusion in pure silicon films to about 2 eV self-diffusion in Ge0.8Si0.2 and Ge. The decrease of the activation enthalpy for amorphous Ge x Si1-x is similar to the case of crystalline Ge x Si1-x . Possible explanations are discussed.

Effect of Au ion irradiation on microstructure, mechanical, and lead‐bismuth eutectic corrosion properties of Cr/ZrO2 coatings

AbstractThe effect of ion irradiation on the microstructure, mechanical, and corrosion properties of Cr/ZrO2 coating was investigated. The monoclinic to tetragonal phase transition is observed under heavy ion irradiation, and the tetragonal phase is stabilized by the irradiation‐induced defect clusters. With increasing irradiation fluence, grain growth, and irradiation‐induced hardening effects are observed. After lead‐bismuth eutectic (LBE) corrosion at 650°C for 1000 h, the irradiated coatings can still maintain structural integrity and protect the substrate from lead/bismuth corrosion. However, in contrast to the unirradiated coating, the irradiation‐induced defects provide a channel for the rapid inward diffusion of oxygen atoms from the LBE, leading to the formation of a thicker Cr‐rich oxide layer beneath the ZrO2 coating. This study also provides insight into how irradiation‐induced microstructural changes affect zirconia's properties as a corrosion protection layer.