Solid-state Diffusion Research Articles

Assessing osseointegration of metallic implants with boronized surface treatment.

Background Modification of endosteal implants through surface treatments have been investigated to improve osseointegration. Boronization has demonstrated favorable mechanical properties, but limited studies have assessed translational, in vivo outcomes. This study investigated the effect of implant surface boronization on bone healing. Material and Methods Two implant surface roughness profiles (acid etched, machined) in CP titanium (type II) alloy implants were boronized by solid-state diffusion until 10-15µm boron coating was achieved. The surface-treated implants were placed bilaterally into 5 adult sheep ilia for three and six weeks. Four implant groups were tested: boronized machined (BM), boronized acid-etched (BAA), control machined (CM), and control acid-etched (CAA). Osseointegration was quantified by calculating bone to implant contact (BIC) and bone area fraction occupancy (BAFO). Results Both implant types treated with boronization had BIC values not statistically different from machined control implants at t=3 weeks, and significantly less than acid-etched control (p<0.02). BAFO values were not statistically different for all 3-week groups except machined control (significantly less at p<0.02). BAFO had a significant downward trend from 3 to 6 weeks in both boronized implant types (p<0.03) while both control implant types had significant increases in BIC and BAFO from 3 to 6 weeks. Conclusions Non-decalcified histology depicted intramembranous-like healing/remodeling in bone for controls, but an absence of this dynamic process in bone for boronized implants. These findings are inconsistent with in vitro work describing bone regenerative properties of elemental Boron and suggests that effects of boron on in vivo bone healing warrant further investigation. Key words:Boronization, acid-etched, machined, implants, osseointegration, in vivo, solid-state diffusion.

A Hybrid Backward Euler Control Volume Method to Solve the Concentration-Dependent Solid-State Diffusion Problem in Battery Modeling

Several efficient analytical methods have been developed to solve the solid-state diffusion problem, for constant diffusion coefficient problems. However, these methods cannot be applied for concentration-dependent diffusion coefficient problems and numerical methods are used instead. Herein, grid-based numerical methods derived from the control volume discretization are presented to resolve the characteristic nonlinear system of partial differential equations. A novel hybrid backward Euler control volume (HBECV) method is presented which requires only one iteration to reach an implicit solution. The HBECV results are shown to be stable and accurate for a moderate number of grid points. The computational speed and accuracy of the HBECV, justify its use in battery simulations, in which the solid-state diffusion coefficient is a strong function of the concentration.

Modelling the high temperature oxidation of titanium alloys: review of analytical models and development of a new numerical tool PyTiOx

In order to limit the ecological impact of air traffic and its operating costs, the aeronautical industry is looking for improving engines efficiencies and substitutes to high density Ni-based superalloys. Thus, a wider use of Ti-alloys operating at higher temperatures is one of the developed solutions. Being able to predict as accurately as possible the oxidation behavior of Ti-based components at high temperatures appears therefore crucial to improve their sizing and durability. Analytical models based on the solid-state diffusion laws can be found in the litterature. They are fairly accurate in most cases, but they reveal some intrinsic limitations in specific cases such as temperature transients or thin components. Numerical models were later developed to break down these limitations. First results from a new numerical tool called “PyTiOx” (still under development are presented here. They confirm the intrinsic limitations of analytical models. In the case of thin samples, the numerical model predicts an increase of scaling kinetic when metal becomes O-saturated, whereas analytical models do not.

Accelerating solid diffusion and suppressing phase transition in LiV3O8via calcium doping at lithium sites.

The phase transition of LiV3O8 from an α phase to a β phase during the discharge/charge process leads to drastic structural change and rapid capacity decay, and the consequent sluggish Li+ solid-state diffusion results in a serious concentration polarization. Herein, Ca-doped LiV3O8 was rationally designed and synthesized to address these issues. The electrochemical behaviors of Ca-doped and undoped LiV3O8, together with their structural evolution and changes in the ion solid diffusion paths, are studied in detail. Calculations at the atomic scale have revealed that Ca doping effectively suppresses the undesired α-β phase transition and stabilizes the structure of LiV3O8 during cycling. Moreover, the calcium dopant preferentially situated at lithium sites in LiV3O8 serves as a pillar to increase the interlayer distance and extend the electrochemically active (001) plane, and thus facilitates anisotropic Li+ diffusion. More importantly, the variable-cell Nudged-Elastic-Band (VCNEB) calculations indicate that the phase transformation was hindered by kinetic factors, not by thermodynamics. The dominant factors for the electrochemical performance of LiV3O8 were clarified, and valuable insights for LiV3O8 commercialization in lithium-ion batteries were provided.

Manufacture of Tungsten Heavy Alloy Tube by Diffusion Bonding of Semicircular Tubes

An innovative manufacturing method to fabricate tubular parts made of tungsten heavy alloy (THA) by diffusion bonding of sintered semicircular tubes is proposed and characterized in this study. THAs are produced by blending tungsten grains with a lower-melting-point Ni-Fe binder metal. During the liquid phase sintering (LPS) process of THA, the Ni-Fe liquid wets the tungsten and provides a soluble diffusion network for rapid sintering. Multi-phase THAs are usually very difficult to produce as a tubular piece. During the LPS of the powder compact, a gravity-induced slumping leads to some distortion in the bottom of the tubular parts. One possible alternative to handle this problem is to combine the segmented THA pieces by solid-state diffusion bonding to build up tubular piece. Thus, this study proposes combining the semicircular THA tubes using the diffusion bonding technique to manufacture the tubular THA parts. To provide uniform contact pressures along the joining surfaces, horizontal diffusion bonding is performed using a specially constructed supporting apparatus to reduce the gravity effect. An industry-applicable tube manufacturing process has been well characterized, and its feasibility has been demonstrated by bond quality that was assessed by optical metallography and mechanical testing.

Coupled molecular dynamics-Monte Carlo modeling of gold nanowire surface fasteners

A novel multiscale model is developed to investigate the mechanical performance of gold nanowires surface fasteners. The cold welding of two contacting nanowires of different diameters and overlapping depth was simulated using molecular dynamics simulations. The strength of the welded interface was obtained via tensile simulations performed at temperatures up to 500 K. A Monte Carlo algorithm was developed to determine the bulk properties of the nanofastener by calculating the average number of welded joints per unit area. Our model shows that the nanojoints are formed by solid-state diffusion and intermixing of the interface atoms. The nanojoints strength increases with the increase of the preloading pressure, leading to the fracture of the nanowire outside the welded region. The results further show that the strength of the nanojoint slightly increases with the increase of the nanowires diameter beyond 10 nm. The effective strength of the fastener was found to increase by four orders of magnitude when the nanowire diameter decreased from 200 nm to 3 nm. Increasing the surface density and improving the patterning accuracy of the nanowire arrays are critical in improving the adhesive performance. The results of the multiscale model are in good agreement with previous experimental measurements.

Experimental investigation and numerical simulation analysis of sintered micro-fluidic devices

ABSTRACTThis study investigates the use of numerical simulations to describe the solid-state diffusion of a sintering stage during a metal injection moulding process for micro-fluidic components with 316L stainless steel powders. Finite element (FE) analysis based on a thermo-elasto-viscoplastic model was conducted to describe the densification process of a stainless steel porous component during solid-state sintering. The numerical analyses, which were performed on a 3D micro-structured component with various powder volume loadings to take into account the thermal debinding effect to propose a full debinding sintering simulation, demonstrated that the FE simulation results are in agreement with the experimental ones.

Maskless Patterning of Metal Outflow in Alternating Metal/Ceramic Multiple Nanolayers by Femtosecond Laser Irradiation

In this work, solid-state metal transport from internal metal nanolayers onto the surface of metal/ceramic nano-multi-layers (NMLs) has been directed in a controlled way by femtosecond (fs) laser irradiation and subsequent low temperature thermal annealing. Laser irradiation induced modifications of the NML microstructures and stress states can be limited within the first few top nanolayers due to the focused laser energy input at the metal/ceramic interface by exploiting the local plasmonic effect. Accompanied laser peening can further refine the crystallites and introduce compressive stress at the laser-irradiated region, which reduces the activation energies for vacancy formation and migration of metal atoms in the nano-confinement. Patterned Cu surface nanostructures (outflow) appear selectively along the laser path after air annealing at temperatures down to 360 ℃. For the solid-state diffusion of Cu in confinement, in-plane metal transport along the Cu-AlN interfaces is much faster than the outward ...

Textured growth of polycrystalline MAX phase carbide coatings via thermal annealing of M/C/Al multilayers

Mn + 1AXn (MAX; n = 1–3) phases are ternary layered nitride and carbide compounds featuring a combination of metallic and ceramic properties. Highly basal-plane textured and polycrystalline Cr2AlC, Ti2AlC, and Ti3AlC2 single-phase coatings have been synthesized on both amorphous and polycrystalline substrates via controlled thermal annealing of magnetron-sputtered nanoscale multilayers built by individual transition metal, carbon, and aluminum layers. Formation of substitutional solid solution carbide phases was triggered via solid-state diffusion reactions during annealing. Lower ordered Ti2AlC initially crystallized at an intermediate temperature range and was recognized as an intermediate reactant in the case of synthesizing the Ti3AlC2 312 MAX phase via annealing corresponding stoichiometric multilayers. The crystallization onset temperatures identified via in-situ high-temperature x-ray diffraction measurements were approximately 480, 660, and 820 °C for Cr2AlC, Ti2AlC, and Ti3AlC2, respectively. Contrary to the usually observed columnar structure representative of magnetron-sputtered coatings, the coatings synthesized via the current approach are composed of plateletlike, elongated crystallites. The nanoscale multilayered design stimulates the textured growth of MAX structures during thermal annealing. More specifically, the preferred crystallographic orientation relationships among the as-deposited transition metal layers, the intermediate solid solution phases, and the end-product MAX phases facilitate the growth of textured MAX phase films.

Modeling void closure in solid-state diffusion bonding of TC4 alloy

An analytical model is developed in effort to characterize the closure of interface void in the joint fabricated using solid state diffusion bonding (SSDB). Based on considering the relationship between the micro-deformation of the contact surface asperities and the macro-deformation of the joint, the model firstly quantitatively predicates the contribution of macro-deformation of joint on the bonding ratio without assuming the interface void geometries before analyzing the mechanisms of plastic and creep deformation. Furthermore, cooperating with the mechanisms of surface and interface diffusion, the correlation between the void closure (i.e. bonding ratio) and bonding parameters is investigated by the model. The results demonstrate that in the early stage of SSDB process, the void closure is mainly resulted from the contributions of the both mechanisms of plastic and creep deformation. However, with bonding time increasing, the mechanisms of surface and interface diffusion gradually become the dominated driving forces until the void elimination. The efficiency and applicability of the analytical model are verified by experimental results of diffusion bonding of TC4 titanium alloy with specially fabricated bonding surface, which demonstrates that the model can successfully forecast the effect of joining parameters on the void closure (or bonding ratio) evolution.

On the complexity of solid-state diffusion in highly concentrated alloys and the sluggish diffusion core-effect

Diffusion paths in system V – Nb – W – Al in the highly concentrated region (i.e. as “High Entropy Alloys”) are modelled using DICTRA code with commercial databases and with a new algorithm, based on the Cluster Variation Method (CVM). The DICTRA simulations, which produce realistic diffusion profiles, show that the diffusion path is non-linear. The CVM simulations, with parameters obtained by ab initio calculations, allow to investigate in an incremental way the effects of thermodynamics, of correlations and the role of the intrinsic diffusivities of the components. The results confirm the non-linear character of the diffusion path, and show that it is primarily driven by the complex thermodynamics characteristic of these alloys. When the intrinsic diffusivities are used, it is observed that the slowest diffusing species (in the present case, W) will constrain the whole diffusion process. This is likely the origin of the so called “sluggish diffusion” effect and it is of kinetic origin, bearing no relation with the configurational entropy.

Interaction of magnesia-carbon refractory with ferrous oxide under flash ironmaking conditions

A novel flash ironmaking technology (FIT) that greatly reduces energy consumption and greenhouse gas emissions compared with blast furnace (BF) ironmaking has been developed at the University of Utah. In this technology, a falling stream of iron ore concentrate is directly converted to metallic iron by reducing gases such as hydrogen, natural gas or coal gas in a flash furnace. In this work, the interaction of magnesia-carbon (MgO–C) refractory with ferrous oxide (FeO) under the conditions of the novel FIT has been investigated. Oxidation of carbon from the MgO–C refractory occurred and magnesiowustite (MgxFe1-xO) solid solution was formed as a result of the interaction between magnesia (MgO) in the refractory and ferrous oxide (FeO). A solid-state diffusion based kinetics model was developed to describe the growth of the magnesiowustite (MgxFe1-xO) formed. Experiments were carried out with ferrous oxide (FeO) and MgO–C refractory in the temperature range 1200–1400 °C under flash ironmaking atmospheres. Reacted samples from FeO–MgO–C experiments were analyzed using Scanning Electron Microscopy-Energy Dispersive X-Ray spectroscopy (SEM-EDX) and Electron Probe Micro-Analyzer (EPMA) and the formation of the magnesiowustite solid solution under flash ironmaking conditions was confirmed. Using the kinetics model and the composition profiles determined with EPMA, the values of interdiffusion coefficient (DFe−Mg) were determined as a function of the magnesiowustite composition. Also, an average value of the interdiffusion coefficient (D‾Fe−Mg) was calculated such that it reasonably reproduced the concentration profile of the cations over the entire composition range. The values of D‾Fe−Mg calculated in this work agreed closely with those obtained independently from experiments on the interaction between MgO–C and metallic Fe, thereby validating the interaction mechanism and the proposed kinetics model. The solid-state diffusion was a thermally activated process and the activation energy (Ea) for D‾Fe−Mg was calculated as 398 kJ/mol.

Interface Formation and Characterization of Brass/Aluminum Compounds Fabricated Through Die Casting and Semi-Continuous Casting

An innovative method based on the static and semi-continuous casting technology is investigated for the production of bilayer brass/aluminum billets and rods. The paper focuses on the interface formation and characterization of metallurgically bonded hybrids consisting of brass CuZn37 and the aluminum alloys AA5083, AA6060 and AA7075. Depending on the thermal process conditions, the interfacial reaction zone between the joining partners exhibits a thickness between a few micrometers and a few millimeters. Regardless of the usage of disparate aluminum alloys, the interface of as-cast brass/aluminum compounds is characterized by four intermetallic layers, namely CuZn $$(\hbox {CuZn-}\upbeta )$$, $$\hbox {Al}_3\hbox {Cu}_5\hbox {Zn}_2$$, $$\hbox {Al}_4\hbox {Cu}_3\hbox {Zn}$$ and AlCu $$(\hbox {AlCu-}\upeta _2)$$, as well as an anomalous eutectic area of aluminum solid solution $$(\upalpha \hbox {-Al})$$, $$\hbox {Al}_2\hbox {Cu}$$$$(\hbox {AlCu-}\uptheta )$$ and eutectic structures. The intermetallic layers are primarily formed by solid-state diffusion, whereas the anomalous eutectic zone is a result of dissolution of Cu in liquid Al and subsequent solidification and precipitation. The microhardness, elastomechanical properties and the bonding strength of the interfacial area of as-cast compounds are determined using the nanoindentation and push-out testing technique. Due to the high cooling rates, brass/aluminum compounds fabricated through semi-continuous casting are characterized by a sufficient geometrical stability of the interface and high bonding quality.

3D phase-field computations of microsegregation in nodular cast iron compared to experimental data and Calphad-based Scheil-prediction

The redistribution of solute elements during processing of a nodular cast iron alloy was simulated for the first time comprehensively over time and 3D space. Numerical predictions had so far been limited to 1D models, neglecting local morphological aspects and commonly also diffusion and growth in solid-state. Application of the standard multi-phase-field method was hindered by the inherent simplifying assumption of equal and constant molar volume, causing artificial piling-up of solute and biased kinetics during modelling of graphite growth. A recently developed volumetric multi-phase-field approach now accounts for the changing partial molar volume of the individual elements. The Calphad-based phase-field study was benchmarked to experimental cooling and nodule density data, and the predicted as-cast distributions were validated by experimental segregation analysis. The combined numerical and experimental findings were furthermore used as a basis to discuss simplifying assumptions commonly made in 1D Scheil-type models.

Diffusion research in HCP Mg–Al–Sn ternary alloys

Diffusion behavior in the HCP Mg–Al–Sn ternary alloys was experimentally investigated at 673 K and 723 K by analyzing solid-state diffusion couples. From the composition profiles analytically represented by error function expansion, the inter- and impurity diffusion coefficients were extracted by the Whittle-Green and generalized Hall methods respectively, which enable to establish the diffusion properties of the HCP Mg–Al–Sn alloys. The present results, together with the binary diffusion data of Mg–Al and Mg–Sn binaries, reveal that the average value of the main interdiffusion coefficient D˜SnSnMg over the investigated compositions is 1.39 times larger than D˜AlAlMg at 673 K and 1.36 times at 723 K, respectively, implying Sn diffuses comparably faster than Al in the HCP Mg–Al–Sn alloys. The main interdiffusion coefficients D˜AlAlMg and D˜SnSnMg and the impurity diffusion coefficient DSn(Mg−Al)* increases with increasing the content of diffusing element, either Al or Sn, however, DAl(Mg−Sn)* increases first and then decreases as the Sn composition increases. The cross interdiffusion coefficients are scattering, their composition dependences are not very conclusive, however, a trend that D˜AlSnMg and D˜SnAlMg become negligibly small or even negative was evidenced as the content of Al or Sn approaches 0.

Energy storage performance and mechanism of the novel copper pyrovanadate Cu3V2O7(OH)2·2H2O cathode for aqueous zinc ion batteries

Aqueous zinc ion batteries (ZIBs) are expected to be used in large-scale energy storage because of their major merits of high-safety, low cost as well as excellent energy density. However, the discovery of high-performance cathode materials and the exploration of zinc storage mechanism are still facing great challenges. Herein, a new cathode material of copper pyrovanadate Cu3V2O7(OH)2·2H2O (CuVO) is demonstrated to be potential in zinc ion storage. A series of ex-situ characterization results reveal a hybrid mechanism involving phase transitions and classical insertion/extraction reaction. First, zinc ions are embedded into CuVO and replace Cu2+ to form a new phase of Zn3(OH)2V2O7·2H2O (ZnVO), and then repeative intercalation of Zn2+ in the ZnVO lattice dominates the subsequent electrochemical reactions. Meantime, a highly conductive Cu0 matrix is generated upon cycling, which effectively enhance the electronic transport. In addition, electrochemical reaction kinetics demonstrate that the CuVO electrode has a significant capacitance contribution and a fast zinc ion solid-state diffusion rate. As a consequence, the CuVO electrode delivers a high specific discharge capacity of 216 mA h g−1 at 0.1 A g−1, and a high capacity retention of 89.3% after 500 cycles at 0.5 A g−1.

Volcanic glass leaching and the groundwater geochemistry on the semi-arid Atlantic island of Porto Santo

The groundwater chemistry of the semi-arid volcanic island of Porto Santo, part of the Madeira archipelago, Atlantic Ocean, was investigated. Generally, the groundwater was brackish, containing 2–10 mol % seawater. Groundwater with up to 20 mM alkalinity and a Na enrichment of up to 30 mM, as compared to the Na concentration predicted by the seawater Na/Cl ratio, was found in the main aquifer. Also notable are the high concentrations of F (up to 0.3 mM), B (up to 0.55 mM), As (up to 0.35 μM), all in excess of WHO recommendations, as well as up to 6 μM V. Geochemical modeling, using the PHREEQC code, was used to explore different scenarios that could explain the genesis of the observed bulk groundwater chemistry. First, a model for aquifer freshening with the displacement of resident seawater from the aquifer by infiltrating freshwater, was tested. This scenario leads to the development of NaHCO3 waters as observed in many coastal aquifers. However, the measured alkalinity concentration in the groundwater was far higher than the concentration predicted by the freshening model. In addition, the behavior of modelled pH and PCO2 were at variance with their distributions in the field data. The second model explored the possible effect of volcanic glass leaching on the groundwater chemistry. Using insight derived from studies of volcanic glass surface alteration as well as experimental work on water-volcanic glass interactions, a geochemical model was developed in which the exchange of H+ for Na+ on the volcanic glass surface is the main mechanism but the exchange of other cations on the volcanic glass surface is also included. The uptake of H+ by the glass surface causes the dissociation of carbonic acid, generating bicarbonate. This model is consistent with the local geology and the field data. It requires, however, volcanic glass leaching to occur in the unsaturated zone where there is an unlimited supply of CO2. The exchange reaction of H+ for Na+ is confined to the surface layer of volcanic glass as otherwise the process becomes limited by slow solid state diffusion of H+ into the glass and Na+ out of the glass. Therefore, volcanic ash deposits, with their high volcanic glass surface areas and matrix flow, are the aquifers where this type of high NaHCO3 waters can be expected, rather than in basalts, which predominantly feature fracture flow. The trace components F, B, As and V are believed to originate from hyaloclastites, consisting of predominantly (90%) of trachy-rhyolite volcanic glass. Although stratigraphically older than the main calcarenite aquifer, topographically they are often located at higher altitudes, above the phreatic level and located along the main recharge flow path. In addition, the semi-arid climate conditions provide a long groundwater residence time for the reactions as well as limited aquifer flushing.

Microstructure and mechanical properties in the solid-state diffusion bonding joints of Ni3Al based superalloy

Directional solidification (DS) of intermetallic compounds Ni3Al based superalloys were joined by solid-state diffusion bonding (SSDB) with the joining interface perpendicular to the solidified direction. The joining process was conducted with a 4 μm pure Ni interlayer at 1100 °C under 15 MPa for 2–7 h. The results showed that the microstructure characteristics of the SSDB joints, microvoids, tiny carbides, a higher volume fraction of γ′ phase and high angle grain boundaries (HAGB) formed in the interlayer region, were significantly different from that of the base metal (BM). The joint of the best mechanical property, strength of 926 MPa and elongation of 7.2%, was produced by the bonding time of 7 h owing to the decrease of the microvoids and the large carbides with the bonding time increasing. However, the relative (ratio between the joint and the BM) tensile strength of the joint was merely 90% due to the existence of high angle grain boundaries (HAGB) generated after the recrystallization of the interlayer. Moreover, because microvoids were not vanished completely and the strain mismatch caused by the structure of the interlayer region, the hard center region (higher volume fraction of γ′ phase) and soft interface region (lower volume fraction of γ′ phase), so the stress concentration were produced between the joint and the BM under the tensile load. Therefore, the relative elongation of the SSDB joint was only 57%.

High-entropy transition metal diborides by reactive and non-reactive spark plasma sintering: A comparative investigation

The direct synthesis and consolidation by SPS (1950 °C, 20 min, 20 MPa) of high-entropy (Hf0.2Mo0.2Zr0.2Nb0.2Ti0.2)B2 from elemental powders resulted in a multiphase product. An increase of the heating rate determined a change of the mechanism governing the synthesis reaction from gradual solid-state diffusion to rapid combustion regime, while the final conversion degree was 67 wt.%. The sintered product displayed a non-uniform microstructure with the presence of 10–15 μm sized pores, due to volatilization phenomena occurring during the combustion synthesis reaction. In contrast, when the SPS process was preceded by powder synthesis via SHS, a homogeneous single-phase ceramic was obtained. Clear benefits are derived by the use of SHS, able to provide very shortly powders with elemental species very well intermixed, so that the obtainment of (Hf0.2Mo0.2Zr0.2Nb0.2Ti0.2)B2 during the subsequent SPS stage is strongly promoted. The resulting 92.5% dense product shows superior oxidation resistance with respect to individual borides prepared with the same method.

Effect of dopant concentration on luminescence properties of a phosphor KCaPO4: Dy

This paper reports for the first time the luminescence (both thermo and photoluminescence) properties of a new phosphor KCaPO4:Dy. The crystallite size of the phosphor prepared by solid-state diffusion method varied from approximately 46 nm–53 nm on varying the concentration of the dopant from 0.1 mol% to 0.4 mol%. Dopant concentration dependent bandgap mechanics in the phosphor was used to explain the behaviour of thermoluminescence (TL) glow curves obtained from gamma and ultraviolet irradiation, and photoluminescence (PL) spectra of the phosphor. Further, this phosphor shows good TL sensitivity towards gamma rays (2.5 times more sensitive than standard TL material TLD-100) and UV rays (20 times more intense than TLD-100). Moreover, the given phosphor shows good linear dose response for gamma rays (with linearity ranging from 10 Gy to 2 kGy) and UV irradiation. Deconvolution was also performed on the glow curves of the given phosphor for gamma irradiation (10 Gy) and UV irradiation (60 min) in order to calculate kinetic parameters for the traps. Other characteristics of the TL material i.e. repeatability and fading were also studied for this phosphor. Decent PL properties with an overall emission lying very near to the white region was observed through the chromaticity index of Commission Internationale de l’E’ clairage (CIE). All these characteristics make the phosphor (with 0.3 mol% Dy concentration) a potential candidate for radiation dosimeter and a UV convertible material for white-light-emitting diodes.