Unirradiated Regions Research Articles

Irradiation Spillover Effect in Photo‐Assisted Ion Batteries: Overcoming Size Limits for Solar Utilization

AbstractPhoto‐assisted ion batteries demonstrate remarkable potential for portable and decentralized solar energy utilization, due to their profound capacity enhancement under irradiation accompanied by promoted discharge voltages. However, ion batteries in practice are highly compact with limited surface area for irradiation. Overcoming the size limit for irradiation is a challenge. Herein, an irradiation spillover effect in photo‐assisted ion batteries is demonstrated, that is the impact of irradiation on the battery is not restrained within the irradiated area but can spillover the whole electrode. This phenomenon is a consequence of the light‐induced potential difference between irradiated and unirradiated regions, leading to selective ion insertion. Irradiated regions favored H+ insertion due to light‐induced proton‐coupled electron transfer, while unirradiated regions preferred Zn2+ insertion. Consequently, the capacity enhancement remains unaffected by halving the irradiated area. This study overcomes the irradiation size limit for photo‐assisted ion batteries and encourages highly integrated photo‐assisted ion batteries for practice application.

Partial-Volume Irradiation of Murine Tumors.

Radiotherapy is a widely used approach for cancer treatment. However, delivering a single high dose of radiation to bulky tumors can be challenging due to the toxicities induced in the surrounding healthy tissue. To overcome this issue, a nonuniform high dose can be delivered using partial-volume tumor irradiation or spatially fractionated radiotherapy (SFRT). Moreover, SFRT has the potential to induce a stronger antitumor immune response compared to traditional radiotherapy due to the preservation of immune cells in the unirradiated tumor regions. There are several SFRT approaches, including GRID therapy, three-dimensional GRID therapy (LATTICE), microbeam radiation therapy (MRT), and Stereotactic Body Radiation Therapy for PArtial Tumor irradiation targeting exclusively the HYpoxic segment (SBRT-PATHY). The following protocol describes partial-volume tumor irradiation, a technique that enables dose delivery to only a part of the tumor in mice using an X-ray generator and collimators of different dimensions that limit the size of the irradiation field.

Ion-irradiation induced hardening behavior of zirconium alloys: A combination of experimental and theoretical study

This study aimed to investigate the microstructure information and mechanical behavior of ion-irradiated zirconium (Zr) alloys through a combination of experimental measurements and theoretical analysis. Experimental procedures involved Au3+ irradiation of Zr-1.5Sn-0.2Fe-0.1Cr and Zr-1.0Sn-1.0Nb-0.1Fe at 3 displacements per atom (dpa) and 30 dpa. Transmission electron microscopy analysis revealed the formation of precipitates such as Zr(Fe, Cr)2 in Zr-1.5Sn-0.2Fe-0.1Cr, as well as β-Nb and Zr(Nb, Fe)2 in Zr-1.0Sn-1.0Nb-0.1Fe. These precipitates exhibited a transformation from crystalline state to partial or complete amorphization after ion-irradiation. Furthermore, macroscopic mechanical properties of the Zr alloys were characterized by nano-indentation tests, which revealed a significant indentation size effect (ISE) and irradiation hardening behavior. To provide a theoretical understanding of the depth-dependent hardness observed in ion-irradiated Zr alloys, a mechanistic model was developed to address the different expansion rates of the plastic zone in the irradiated and unirradiated region. The results indicated that the ISE phenomenon could be attributed to the reduction in the density of geometrically necessary dislocations (GNDs) caused by the expansion of the plastic zone. In addition, the irradiation hardening behavior primarily resulted from the contribution of irradiation-induced defects. With increasing indentation depth, the dominant hardening mechanisms changed from the contribution of irradiation-induced defects, GNDs and statistically stored dislocations (SSDs) in the irradiated region to SSDs in the unirradiated substrate.

Multi-responsive P(DMAEMA-co-COU) hydrogel for temperature sensor and information encryption

Multi-responsive hydrogels for temperature sensor and information encryption were developed through the synergistic application of light, temperature and pH response of the hydrogel. The multi-responsive hydrogels were prepared by copolymerization of dimethylaminoethyl methacrylate (DMAEMA) and 7-(2-methacryloyloxyethoxy)-4-methylcoumarin (CoumMAc). Through incorporating coumarin groups into the hydrogels, the crosslinking degree of hydrogels could be increased by photo-crosslinking of polymer chains based on the photodimerization of coumarin groups. After the hydrogel was irradiated by a photomask under UV light (365 nm), the irradiated and unirradiated region in the hydrogel showed different crosslinking degrees, leading to different volume phase transition temperature (VPTT) in the two region of the hydrogel. The pattern in the hydrogel appeared only within a specific temperature range, and the temperature of the environment can be monitored by the prepared hydrogel sensor. After soaking the patterned hydrogel in the acidic solution, no pattern information was displayed at all temperatures, and the pattern information can only emerge by dual decryption (base and temperature). In addition, the information can be erased by UV light (254 nm), which further ensures information security. This work provide a new way for low-cost unpowered temperature sensors and information encryption with more security.

PREOPERATIVE BRAIN IRRADIATION IN GLIOBLASTOMA (POBIG TRIAL): FEASIBILITY AND EVALUATION OF TREATMENT RESPONSE IN ENHANCING AND NON-ENHANCING REGIONS

Abstract AIMS Patients with glioblastoma have dismal outcomes and there is an urgent need for new treatment modalities. The POBIG trial is the first to evaluate the safety and feasibility of single-fraction preoperative radiotherapy for newly diagnosed glioblastoma. We report the results from our first dose arm. METHOD POBIG is a phase I radiotherapy dose and volume escalation trial. The first dose arm received 8Gy preoperative radiotherapy to a maximum irradiation volume of 30cm3. The irradiation field included enhancing and non- enhancing FLAIR hyperintense regions judged as highest risk for remaining as postoperative residuum. Part of the tumour remained unirradiated (<2Gy) with a margin for diagnostic sampling. Surgical resection took place within 1 week. Patients underwent diffusion/perfusion MRI scans before/after preoperative radiotherapy. RESULTS Two female and one male patient aged 61, 67 and 45 years, respectively, were enrolled. Preoperative radio- therapy was delivered at a dose of 8Gy to an irradiation volume of 7-30cm3. Near-total surgical resection was performed 2-3 days after preoperative radiotherapy treatment. Pathological examination of irradiated areas showed necrosis including fibrinoid necrosis of vessel walls. There was an increase in Ktrans permeability in both irradiated enhancing tumour (0.097,0.150) and unirradiated enhancing tumour (0.077,0.147) 24-hours after treatment. In contrast, no obvious changes were noted in irradiated (0.002,0.002) and unirradiated (0.002,0.004) non-enhancing FLAIR hyperintense regions or reference unirradiated contralateral white matter (0.000,0.000). CONCLUSIONS Preoperative radiotherapy is feasible in newly diagnosed glioblastoma. Very early radiotherapy changes manifest in enhancing tumour regardless of radiotherapy dose, evident as increased permeability and radiation- induced tumour necrosis.

Clarifying the irradiation effect on the general oxidation of 316L stainless steel in high temperature hydrogenated water after 1000h immersion

The role of proton irradiation in the general oxidation of 316 L stainless steel in simulated PWR primary water after 1000 h immersion was clarified by comparing the microstructural and microchemical features of oxides formed on both the irradiated and un-irradiated regions of identical grains. Hence, the interference from differences in crystallographic orientation can be ruled out. Interestingly, the average inner oxide thickness on the irradiated region is significantly thinner than that on the un-irradiated region. The enhanced resistance to oxidation on the irradiated region originates from the more protective inner oxide layer and the formation of a continuous Ni-rich zone near the oxide/matrix interface. The inner oxide formed on irradiated region is less deficient in cation due to the enhanced diffusion of Cr from matrix by the irradiation-induced defects, thus making a better diffusion barrier. Meanwhile, the formation of continuous Ni-rich zone near the oxide/matrix interface, which is facilitated by the Ni-rich defects serving as nuclei, fast generation of vacancy at the interface and suppression of the outward diffusion of surplus Ni, can diminish the available space for the growth of inner oxide. The limited oxidation space and high Cr content at the oxide/matrix interface in the irradiated region result in the formation of rocksalt oxide while spinel oxide is formed near the interface in the un-irradiated region.

Surface patterning in thin ternary composites based on Zr, In and C irradiated with 2 MeV W+ ions

A number of sophisticated methods are related to the technology of thin-film complex materials. One of them, although less used, is the sputtering of targets with low-energy ions. Using this method, various thin multi-element composites can be formed either as amorphous mixtures or crystalline structures (e.g. MAX phases), or something in between. In this work, 25 keV Ar+ ion sputtering was used to synthesize thin ternary systems based on Zr, In, and C with a stoichiometric ratio of ∼2:1:1. The prepared samples were exposed to 2 MeV W+ ion irradiation (for comparison, 1/3 of each sample remained pristine) to determine their response to heavy ion bombardment. The analysis was focused mainly on the surface morphology. It has been shown that using ion sputtering, thin ternary composites with a very smooth surface and homogeneously distributed phases can be prepared. After ion bombardment, well distinct self-organized structures appeared – parallel nanostripes growing in several directions on both irradiated and unirradiated regions of the composites. As a driving force of the patterns, an immiscibility of the building elements In and C was proposed. The process of the self-assembly consists in the coordinated expansion of the phase separation that occurs at elevated temperatures induced by ion irradiation. The results indicate that using ion beam sputtering with subsequent MeV ion bombardment, multi-element thin-film composites exhibiting self-organized morphology can be synthesized.

CTNI-66. THE PREOPERATIVE BRAIN IRRADIATION IN GLIOBLASTOMA (POBIG) STUDY: A NOVEL TREATMENT PARADIGM TO IMPROVE OUTCOMES?

Abstract OBJECTIVE The Preoperative Brain Irradiation in Glioblastoma (POBIG) study evaluates for the first time the safety, feasibility, and impact of single fraction preoperative radiotherapy in newly diagnosed glioblastoma patients. METHODS Operable patients with a radiological diagnosis of glioblastoma, by consensus of a multidisciplinary tumor board including two dedicated neuro-radiologists, are screened for the study. Anatomical and functional MRI sequences are acquired for further tumor characterization and preoperative radiotherapy planning. Radiotherapy is delivered approximately two weeks after the initial screening. Radiation targets the macroscopic and microscopic tumor region at risk of being left behind during surgery and spares at least 2cc tumor volume being debulked to safeguard unperturbed and clinically relevant tissue examination and molecular profiling. The study dose-escalates (from 8Gy to 14Gy) based on the time-to-event Continual Reassessment Methodology. Subsequently, patients undergo surgical debulking followed by postoperative fractionated radiotherapy 60Gy/30fr with concurrent temozolomide. RESULTS The first POBIG study patient underwent preoperative radiotherapy followed by a subtotal resection of a left posterior fronto-opercular tumor and completed the postoperative chemoradiotherapy. Screening, study consent, MRI imaging and analysis, radiotherapy planning and delivery until surgery can be achieved within three weeks from screening while maintaining adequate and personalized patient communication. There were no surgical or radiotherapy delays or complications. During surgery, we successfully sampled unirradiated and irradiated tumor regions. The radiotherapy field covered the whole remnant tumor, and image-guided obtained tumor samples and imaging analysis showed clear evidence of differential radiation-induced changes. CONCLUSION We successfully initiated a new treatment strategy of preoperative radiotherapy for glioblastoma patients. The first patient completed the treatment, and the study is now open for further recruitment. Paired tumor sampling and advanced imaging analysis showed promising results. The POBIG study offers a unique opportunity for a paradigm shift towards personalized treatment regimens, hopefully leading to better outcomes.

Clarifying the mitigation effect of proton irradiation on the intergranular oxidation of 316L stainless steel in high temperature water

The role of proton irradiation in the intergranular oxidation of 316L stainless steel after long-term immersion in simulated PWR primary water was clarified by comparing the microstructural and microchemical features of oxide between the irradiated grain boundary (GB) and its un-irradiated counterpart. As such, the interference from difference in GB structure can be ruled out. Surprisingly, the results reveal that the intergranular oxide penetration in the irradiated region is shallower than that in the un-irradiated region. It is found that Si segregated at the irradiated GB diffuses outwards preferentially and gets oxidized due to its high diffusivity and affinity to oxygen. The Si-enriched oxide in the intergranular oxide tip of irradiated GB can act as a temporary diffusion barrier for oxygen, although it tends to dissolve near the sample surface. Meanwhile, the efficiency of elements (especially Cr) transport along irradiated GB to the oxidation front is promoted mainly due to the vacancies created by preferential diffusion of Si, resulting in higher Cr content at the intergranular oxide tip. The combination of Si and Cr enrichments in the intergranular oxide tip can enhance the resistance to oxidation and eventually leads to a lower oxidation rate for the irradiated GB. For the first time, our study determines that irradiation can enhance the intergranular oxidation resistance of stainless steel after long-term immersion in simulated PWR primary water when the sample is not stressed.

Site-selective low-temperature growth of Au nanowires on Si substrates irradiated with low-energy Ar ions

We demonstrated the site-selective growth of freestanding single-crystalline Au NWs at a low temperature (approximately 573 K) by pretreating a silicon substrate with low-energy ion beams, followed by thermal evaporation of Au. Using this method, Au NWs with aspect ratios up to 1000 or more, that is, 50–200 nm in diameter and lengths ranging from several hundred nanometers to approximately 100 μm, were fabricated. Au NWs could only be grown at the boundary between the ion-irradiated and unirradiated regions on the Si substrates during the deposition of Au. Furthermore, patterning the Si substrate by masking it with a fine mesh during ion irradiation creates more boundaries between the irradiated and unirradiated regions, increasing the number of Au NWs. Transmission electron microscopy and selected-area electron diffraction revealed that the NWs were single crystals and grew along the [110] direction.

Plasticity improvement and radiation hardening reduction of Y doped V-4Cr-4Ti alloy

In current work, V-4Cr-4Ti and V-4Cr-4Ti-2Y alloys are prepared using mechanical alloying and spark plasma sintering. Sequential-beam irradiation of 30 keV H+ and 50 keV He+ ions, are carried out at 450 ℃ to the peak damage of 0.18 dpa. The influence of Y on the microstructure, mechanical properties, radiation induced defect and radiation-hardening are investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), mechanical test, and nano-indentation test. Two kinds of Y-rich particles precipitated in Y added alloy, one is Y2O3 phase with a mean size of 60 nm, the other is YVO4 with a diameter of ∼10 nm, but no carbide of Y is observed. The results show that Y can significantly improve plasticity of V base alloy, reduce the size and number density of radiation induced dislocation loops, limit radiation hardening. Two different fitting process with different initial values and boundary conditions are used to analysis radiation hardening, the fitting results indicate a slight softening of matrix near damage layer which named softened layer. This softened layer can affect nanoindentation test results especially for shallow irradiation. A plausible explanation for the formation of this softened layer could be the oxygen diffuses from unirradiated region to damage layer.

Physical Testing and Surface Morphology Studies of Stainless Steel Irradiated with Xe Ions

6 MeV Xe ions were used to irradiate austenitic stainless steel at room temperature. Three displacement damage levels of 2,7 and 15 dpa were selected. Microstructure and surface morphology were characterized by transmission electron microscopy (TEM), positron annihilation lifetime spectroscopy (PLS) and atomic force microscope (AFM). PLS indicated that vacancy defects were introduced by ions irradiation. Vacancy clusters containing Xe will reduce the positron annihilation lifetime. High density of dislocation loops were observed by TEM. The dislocation loops size and density saturates after 7 dpa and the nature of dislocation loops can be deduced by its distribution. A surface step was detected by AFM measurements between irradiated region (uncovered) and unirradiated region (covered with nickel mesh). This indicate that the irradiation swelling phenomenon occur and swelling is closely related to irradiation damage. According to the step height, the volume swelling is about 1.7% and 4.2% after irradiated to 7 and 15 dpa.

Formulating Multiphase Medium Anti-wetting States in an Air-Water-Oil System: Engineering Defects for Interface Chemical Evolutions.

Studies which regulate macroscopic wetting states on determined surfaces in multiphase media are of far-reaching significance but are still in the preliminary stage. Herein, inspired by the wettability subassembly of fish scales, Namib desert beetle shell, and lotus leaf upper side, interfaces in the air-water-oil system are programmed by defect engineering to tailor the anti-wetting evolution from double to triple liquid repellency states. By controlling the visible light irradiation and plasma treatment, surface oxygen vacancies on CuxO@TiO2 nanowires (NWs) can be healed or reconstructed. The original membrane or the membrane after plasma treatment possesses abundant surface oxygen vacancies, and the homogeneous hydrophilic membrane shows only double anti-wetting states in the water-oil system. By the unsaturated visible light irradiation time, the surface oxygen vacancy partially healed, the heterogeneous hydrophilic-hydrophobic components occupied the membrane surface, and the anti-wetting state finally changed from double to triple in the air-water-oil system. After the illumination time reaches saturation, it promotes the healing of all surface oxygen vacancies, and the membrane surface only contains uniform hydrophobic components and only maintains double anti-wetting state in the air-oil system. The mechanism of the triple anti-wetting state on a heterogeneous surface is expounded by establishing a wetting model. The wetting state and the adhesion state of the CuxO@TiO2 NW membrane show regional specificity by controlling the illumination time and region. The underwater oil droplets exhibit the "non-adhesive" and "adhesive" state in a region with unsaturated irradiation time or in an unirradiated region, respectively. Underwater oil droplet manipulation can be accomplished easily based on switchable wettability and adhesion. Current studies reveal that defect engineering can be extended to anti-wetting evolution in the air-water-oil system. Constructing an anti-wetting interface by heterogeneous components provides reference for designing the novel anti-wetting interface.

High-throughput ion irradiation of additively manufactured compositionally complex alloys

Several advanced nuclear reactor designs promise efficiency and safety improvements over the current reactor fleet but are limited by the current set of ASME code-qualified materials. Novel alloys including high-entropy alloys (HEAs), and more broadly compositionally complex alloys (CCAs), have shown promising irradiation-tolerance. However, the vast range of alloy compositions adds to an already time-consuming alloy development process. In this study, to accelerate the development of novel alloys for nuclear applications, a high-throughput (HTP) methodology has been employed. Additive manufacturing has been used to produce a compositional array of unary, binary, ternary, and quaternary alloys, including several CCAs, which span the Cr-Fe-Mn-Ni composition space. The compositional array was homogenized at 1000°C for 24 hours and each sample was irradiated using 4-MeV Ni2+ ions at room temperature to a peak damage of 50 dpa, as estimated using SRIM, at the University of Wisconsin Ion Beam Laboratory. A custom XY stage was built to accommodate the large compositional array and half of each sample was masked during irradiation enabling both the irradiated and unirradiated properties of each alloy to be characterized side-by-side. Each alloy was characterized using X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and nanoindentation. CALPHAD simulations spanning the entire Cr-Fe-Mn-Ni composition space at 1000°C were performed to compare predicted equilibrium phases with phases identified experimentally from the unirradiated regions of each alloy. Nanoindentation measurements indicate radiation-induced hardening ranging from ~1-1.5 GPa in each of Cr-Fe-Mn-Ni CCAs, which is relatively insensitive to modest changes in alloy composition and comparable to hardening observed in neutron irradiated Cr-Fe-Mn-Ni CCAs in the literature. Overall, a substantial time savings was realized by employing HTP synthesis, irradiation, and characterization in this study compared to conventional techniques, the implications of which are discussed.

Absorption characteristics of silver ion-exchanged layers in chloride photo-thermo-refractive glass

Subject of Research. The paper considers effect of chloride in composition of photo-thermo-refractive glass on the spectral properties of silver nanoparticles formed in ion-exchanged layers after heat treatment. Method. Glasses based on Na2O–ZnO–Al2O3–SiO2–F doped with antimony oxide Sb2O3, cerium oxide CeО2 and a variable chloride content (0–1 mol%) were synthesized for the study. Silver ions were introduced by the low-temperature Na+–Ag+ ion exchange method into the synthesized glasses. For this purpose, glass samples were immersed in a mixture of 0.1AgNO3/99.9NaNO3 (mol%) nitrates at the temperature of 320 °С for 15 minutes. After the ion exchange glasses were irradiated with ultraviolet radiation and heat-treated at the temperature of 500 °C for 3 hours to achieve the growth of silver nanoparticles. Main Results. Spectrum properties of chloride photo-thermo-refractive glasses with silver nanoparticles in ion-exchanged layers are studied. It is found that the presence of chloride in the photo-thermo-refractive glass matrix results in a long-wavelength shift of the absorption band of silver nanoparticles. That may be attributed to the growth of the mixed AgCl/NaCl shell on silver nanoparticles. The formation of silver nanoparticles in ion-exchanged layers occurs both in the irradiated and unirradiated regions of the glass. Practical Relevance. The results can be used to create Bragg gratings inside photo-thermo-refractive glass for input and output radiation (pump and signal) into the waveguide structures formed by the ion exchange method, and to create monolithic integrated optical elements on a single substrate, that is very essential for integrated optics

Structural damage and phase stability of Al0.3CoCrFeNi high entropy alloy under high temperature ion irradiation

An initially single phase high entropy alloy (HEA) Al0.3CoCrFeNi was irradiated by 3 MeV Au ions to a fluence of 6 × 1015 cm−2 (∼31 dpa at damage peak) at four different temperatures ranging from 250 °C to 650 °C. Transmission electron microscopy (TEM) and Atom probe tomography (APT) were employed to study the evolution of structural damage and phase stability with irradiation temperature. Al0.3CoCrFeNi exhibited a similar evolution of irradiation-induced defects with temperature as compared with conventional FCC alloys. At 250 °C and 350 °C, most of the visible irradiation-induced defects were faulted 1/3〈111〉 dislocation loops. As the irradiation temperature increased to 500 °C, perfect 1/2〈110〉 dislocation loops were observed along with the faulted loops. At the highest irradiation temperature 650 °C, only dislocation lines and networks could be observed. Regarding phase stability, the 3 MeV Au irradiation was observed to suppress the precipitation of (Ni, Al)-enriched nano clusters and the L12 ordered structure at irradiation temperatures 250 °C to 500 °C whereas precipitation of the B2 ordered structure was accelerated at 650 °C. This resulted in qualitatively opposite precipitation behavior between the ion irradiated damage region and unirradiated region at 500 °C and 650 °C. The opposite phase stability of the ion-irradiated damage region and unirradiated region at different temperatures is attributed to the competing effects of ballistic dissolution vs irradiation enhanced diffusion on precipitation.

Selective crack suppression during deformation in metal films on polymer substrates using electron beam irradiation

While cracks are usually considered detrimental, crack generation can be harnessed for various applications, for example in ceramic materials, via directing crack propagation and crack opening. Here, we find that electron beam irradiation prompts a crack suppression phenomenon in a copper (Cu) thin film on a polyimide substrate, allowing for the control of crack formation in terms of both location and shape. Under tensile strain, cracks form on the unirradiated region of the Cu film whereas cracks are prevented on the irradiated region. We attribute this to the enhancement of the adhesion at the Cu–polyimide interface by electrons transmitted through the Cu film. Finally, we selectively form conductive regions in a Cu film on a polyimide substrate under tension and fabricate a strain-responsive organic light-emitting device.

Corrosion behavior of ion-irradiated SiC in FLiNaK molten salt

High-purity 4H-SiC samples exposed to 1-MeV Si ions irradiation at RT were corroded in FLiNaK molten salt at 650° C for 168 h. Results revealed the corrosion degree of irradiated SiC was dependent on the irradiation fluence. The amorphous region induced by irradiation was preferentially corroded, where Si elements could dissolve into the salt more easily than those in the unirradiated region. The dissolution of Si elements caused the formation of sustained nanocracks and nanopores, and thus the corrosion layer having a thickness of 200 ± 50 nm fell off. Moreover, oxygen impurities might play a role in the irradiation-assisted corrosion.

Proton irradiation effects on the electron work function, corrosion and hardness of austenitic stainless steel phases

The effects of proton irradiation on the electron work function of the 308 L austenitic stainless steel weld metal were investigated by scanning Kelvin probe force microscopy. The electron work function of ferrite increased, while austenite decreased after proton irradiation on the irradiated surface. The electron work function of the two phases decreased with irradiation depth. Softening of austenite and hardening of ferrite by irradiation with an obvious boundary between the irradiated and unirradiated regions on the polished cross-section surface were measured by nanoindentation. The corrosion morphology was consistent with the electron work function measured in the cross-section.

Evolution of the microstructural and mechanical properties of BAM-11 bulk metallic glass during ion irradiation and annealing

Ion irradiation and annealing experiments were performed on Zr52.5Cu17.9Ni14.6Al10Ti5 “BAM-11” bulk metallic glass (BMG) specimens to evaluate their irradiation- and temperature-induced microstructural and mechanical property evolution. For the ion irradiations, samples were exposed to 9 MeV Ni3+ ions to a midrange (∼1.5 nm depth) dose of 10 displacements per atom (dpa) at temperatures ranging from 25 to 360 °C. A separate set of samples were annealed at 150 °C, 200 °C and 300 °C with respective heating times of 96, 72, and 48 h. Bulk X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterization revealed that the alloy did not crystallize during irradiation up to 290 °C, although partial crystallization occurred at 360 °C throughout the unirradiated and irradiated regions of the sample. Transmission electron microscopy (TEM) characterization suggested that some of the irradiated region retained an amorphous structure, supporting the idea of partial crystallization. XRD analysis revealed that the crystallization which occurred in the sample irradiated at 360 °C was caused by thermal effects, and not irradiation displacement damage, and may be due to slight impurity contamination in the ingot. Nanoindentation experiments showed that only a slight amount of hardening was observed in the specimen irradiated at room temperature and 290 °C. However, significant hardening occurred in the sample irradiated at 360 °C (∼18% increase) as well as the unirradiated annealed specimens. For the sample irradiated at the highest temperature, the substantial increase in hardness was attributed to the partial crystallization of the alloy due to thermal, rather than irradiation effects. Overall, the results of the XRD and nanoindentation characterizations indicate good stability during irradiation at 25–290 °C but suggest that the BAM-11 BMG is not suitable for irradiation environments where temperatures exceed 300 °C for prolonged periods of time. Three different extrapolation models were employed to study how irradiation and annealing modify the indentation size effect (ISE) in the BAM-11 BMG. The poor linear fitting, as exhibited by all of the underlying equations, indicate that a new ISE model is needed to quantify nanoindentation mechanical properties in BMGs.