Yttria-stabilized Zirconia Samples Research Articles

Extreme temperature gradient promoting oxygen diffusion in yttria‐stabilized zirconia: A molecular dynamics study

AbstractThe oxidation resistance of yttria‐stabilized zirconia (YSZ) thermal barrier coatings and conductivity of YSZ solid oxide fuel cells are closely related to the diffusion of oxygen ions () in YSZ, but the diffusion behavior in small‐sized YSZ samples under non‐isothermal condition where the temperature gradient () could be significant remaining elusive. Herein, we disclose the previously unrevealed effect of extreme on the self‐diffusion behavior of in both pristine and strained YSZ. It is found that the self‐diffusion coefficient () experiences a nearly one‐fold increase under an extreme around 60 K/Å. The diffusion direction tends to be toward regions of high temperature. Uniaxial stress is revealed to reduce due to the increased activation energy of ions, whereas promotes the self‐diffusion in the stressed system. These results underscore the role of in influencing the self‐diffusion behavior of YSZ, providing a theoretical guideline for examining ceramics serving in extreme environments.

Grazing-incidence synchrotron radiation diffraction studies on irradiated Ce-doped and pristine Y-stabilized ZrO2 at the Rossendorf beamline.

In this work, Ce-doped yttria-stabilized zirconia (YSZ) and pure YSZ phases were subjected to irradiation with 14 MeV Au ions. Irradiation studies were performed to simulate long-term structural and microstructural damage due to self-irradiation in YSZ phases hosting alpha-active radioactive species. It was found that both the Ce-doped YSZ and the YSZ phases had a reasonable tolerance to irradiation at high ion fluences and the bulk crystallinity was well preserved. Nevertheless, local microstrain increased in all compounds under study after irradiation, with the Ce-doped phases being less affected than pure YSZ. Doping with cerium ions increased the microstructural stability of YSZ phases through a possible reduction in the mobility of oxygen atoms, which limits the formation of structural defects. Doping of YSZ with tetravalent actinide elements is expected to have a similar effect. Thus, YSZ phases are promising for the safe long-term storage of radioactive elements. Using synchrotron radiation diffraction, measurements of the thin irradiated layers of the Ce-YSZ and YSZ samples were performed in grazing incidence (GI) mode. A corresponding module for measurements in GI mode was developed at the Rossendorf Beamline and relevant technical details for sample alignment and data collection are also presented.

Grain boundary effects on thermal shock responses of yttria-stabilized zirconia

The rapid temperature change or thermal shock is inevitable in many engineering applications of polycrystalline yttria-stabilized zirconia (YSZ). Nevertheless, the thermal shock response of YSZ especially its dependence on the grain boundary (GB) structure in YSZ remains almost unknown to date. In this study, the effect of the GB on thermal shock behaviors of YSZ ceramics was investigated by molecular dynamics (MD) simulations in conjunction with experimental characterizations. According to the distribution of misorientation angles of GBs experimentally extracted from our sintered YSZ samples, four most common GBs with a misorientation angle ranging from 35° to 63° were constructed in MD simulations through the annealing technique. The thermal shock simulations on the bi-crystalline YSZ with such GBs show a weakening effect of the GB on the thermo-elastic strain wave, which is found to be the most significant in the [100]/[111] GB and almost vanish in its [110]/[111] counterpart. Our simulations also reveal that the weakening effect of GB on the thermo-elastic strain wave is majorly attributed to the impedance mismatch between its two adjacent grains, although the grain-boundary thermal resistance observed also can weaken the temperature wave after crossing GBs. These findings provide valuable atomic insights into the thermomechanical behaviors of YSZ under thermal shock, which will guide the design of microstructures of YSZ for some special applications in solid oxide fuel cells and thermal barrier coatings.

Translucent multi-layered zirconia: Sandblasting effect on optical and mechanical properties.

The aim of this study was to evaluate the influence of the sandblasting treatment on the microstructure, optical and mechanical properties of multi-layered translucent zirconia. Samples of yttria-stabilized zirconia were prepared by stratifying four layers (L1, L2, L3 and L4) of ML-type KATANA multi-layered monolithic discs, whose surfaces were then sandblasted with alumina particles (110µm and 0.2MPa) in order to evaluate its effect on the presence of different crystalline phases as well as on the optical and mechanical properties of each of the four layers. The optical characterization was carried out by measuring the reflectance spectrum and colorimetric parameters by UV-Vis spectrophotometric analysis and the transmittance curves were indirectly obtained using the Kubelka-Munk model (KM). Microstructural, structural, mechanical and roughness characterizations were also performed using SEM, XRD, biaxial flexural strength B3B, and light interferometry, respectively RESULTS: According to the KM model there are different degrees of translucency between the upper and lower layers of the monolithic discs, but there was no influence of the Al2O3-sandblasting treatment on this optical property. The disk pigmentation causes greater absorption of light below 600nm, decreasing the transmittance rate to values below 25% in this region of the spectrum. The yellowing index presented higher values for inner disk layers L3 and L4, in agreement with the highest values of the light absorption coefficient K observed for these layers. The roughness of the samples did not change significantly with the surface treatment performed and the sandblasting did not result in new crystalline phases. SEM analysis showed the presence of different grain sizes in all layers analyzed, being related to the co-occurring presence of cubic (c-ZrO2) and tetragonal (t-ZrO2) phases in similar contents (∼ 50wt%). The Weibull statistical analysis, in turn, showed an increase in the Weibull characteristic stress value (σ0) for most layers subjected to sandblasting, except for the second layer (central region of the disk). It was also verified an increase in the value of the structural reliability of the material (m), referring to the samples of the central region of the disc (L2 and L3 layers) after sandblasting. The pigmentation in the disk causes a decrease of the transmittance rate to values well below 25% in the region of the spectrum 400-600nm and the inner layers (L3 and L4) have even lower transmittance than the outer layers in this spectrum range. Although the CR index indicates variation related to the Al2O3-sandblasting treatment, the transmittance spectra of KM model show that the sandblasting did not cause a significant change in the transmittance rate of the four analyzed layers. Also, there is no significant difference in the light scattering of the different layers of the disc, either before or after Al2O3-sandblasting treatment.

Gradual modification of the YSZ structures by Au ion implantation and high-energy Si ion irradiation

Gold nanoparticles (Au-NPs) were created in crystalline yttria-stabilized zirconia (YSZ). (100)-, (110)- and (111)-oriented YSZ samples were implanted by 1 MeV Au+ ions at room temperature and fluences ranging from 1.5 × 1016 cm−2 to 7.5 × 1016 cm−2. The prepared Au: YSZ structures were annealed at 1100 °C for 1 h on air to support the Au-NPs coalescence and YSZ structure recovery. Subsequent irradiation with the 10 MeV Si3+ ions with a fluence of 5.0 × 1014 cm−2 was performed to enable gradual modification of Au-NPs. Au-depth profiles and YSZ structure modification in the produced samples were analysed via Rutherford backscattering spectrometry in channelling mode (RBS-C) and X-ray diffraction (XRD). RBS-C showed the gold distributed in the region of about 50–300 nm below the YSZ surface. The disorder was accumulated in the region with Au-NPs and the concentration of the disorder increases as a function of ion implantation fluence. The Zr-disorder was partially decreased after the annealing, while the subsequent Si-ion irradiation increased Zr-disorder again, however, the disorder does not reach values before the annealing. XRD measurement evidenced elastic deformation of the YSZ host lattice in the Au-implanted samples. Optical absorbance showed the appearance of the new absorption band at 550 nm for the Au-ion fluences above 5.0 × 1016 cm−2 ascribed to the Au-NPs formation. After the annealing, the absorption band is shifted to the wavelength of 580 nm which could be connected to the proceeding clustering of Au. The maximum absorption peak intensity increases which is connected to the increasing amount of the Au-NPs. Transmission electron microscopy (TEM) with Energy dispersive spectroscopy (EDS) confirmed the presence of Au-NPs in the implanted layer after the annealing. The subsequent Si-ion irradiation did not change the Au-NP shape which remained spherical with a slight size increase.

A SiPM-based dual and triple coincidence system for positron annihilation lifetime measurement

Positron annihilation lifetime (PAL) spectroscopy is a powerful non-destructive method to study defects in materials. Silicon photomultipliers (SiPMs) have emerged as promising photodetector alternatives for PAL systems. However, further research is needed to fully optimize SiPM arrays for PAL applications. In this study, a dual and triple coincidence system has been developed based on four 1 × 4 SiPM arrays with resistor-chain readout, and initial results of PAL measurement have been obtained. A pixel-by-pixel time shift correction method was proposed and successfully applied using triple γ coincidence for summing 128 PAL spectra in one measurement. The system provides position, timing, and energy information for both 1275 and 511 keV γ-rays. The use of SiPM arrays and the pixel-by-pixel time shift correction method have enabled precise and reliable measurements of PALs in single-crystal silicon and yttria-stabilized zirconia samples. The developed SiPM-array-based PAL system also offers a technical solution to measure angular correlations of positron annihilation radiation, with the potential for further improvements.

Up-Conversion Photoluminescence in Thulia and Ytterbia Co-Doped Yttria-Stabilized Zirconia Single Crystals

ZrO2 is an attractive host matrix for luminescence material because of its excellent physical properties, such as low phonon energy and wide band gap. In this work, the highly transparent Tm2O3 and Yb2O3 co-doped yttria stabilized zirconia (YSZ) (abbreviated as Yb/Tm: YSZ) single crystals were grown by the optical floating zone method. The Yb/Tm: YSZ samples were stabilized in the cubic phase at room temperature when Yb3+ and Tm3+ replaced Y3+. The influence of Yb3+ co-doping on the up-conversion luminescence properties of the crystals was systematically studied. A total of 0.5 mol% Tm2O3 and 2.0 mol% Yb2O3 co-activated YSZ single crystal (abbreviated as 2.0Yb/Tm: YSZ) has the maximum luminous intensity. There were seven absorption peaks located at around 358, 460, 679, 783.3, 850–1000, 1200, and 1721.5 nm that were observed in the absorption spectrum of the 2.0Yb/Tm: YSZ single crystal. There were three up-conversion peaks at around 488, 658 and 800 nm that were observed when the Yb/Tm: YSZ samples were excitated at 980 nm. The fluorescence lifetime of Tm3+ for the 1G4→3H6 transition of the 2.0Yb/Tm: YSZ sample is 7.716 ms as excited with a 980 nm laser. In addition, the oscillator strength parameters Ωλ (λ = 2, 4 and 6) of this sample were derived by the Judd–Ofelt theory to evaluate the laser performance of the host materials. The ratio Ω4/Ω6 of this sample is 0.80, implying its excellent laser output. Therefore, the 2.0Yb/Tm: YSZ single crystal is a considerable potential material for laser and luminescence applications.

Structure and Properties of 3D Printed Zirconia Applied in Dentistry

During the last years, the interest in the application of the additive manufacturing (AM), also known as 3D printing, becomes extremely popular in the various fields of the medicine including the dentistry. Currently, metal and ceramic materials are most often used for dental prosthetics manufactured by 3D printing. The yttria-stabilized zirconia (YSZ) ceramics has become the best alternative for metal-based dental restorations. In this regard, the main goal of this review deals with studying the effect of the 3D printing parameters on the macro- and microstructure and, accordingly, on the mechanical properties of the sintered YSZ, and on this basis, to give the practical recommendations to clinical dentistry and further prospects. As most researched in recent years, the 3D printing methods of such ceramics are the Laser-Stereolithography (Laser-SL) and the Stereolithography-Digital Light Processing (SL-DLP) based on the vat-photopolymerization technology and are discussed here. The physical foundations and the technological parameters of these AM technologies are considered. The main attention focuses on the effects of the thermal conditions during the 3D printing on the solidification microstructure (density, grain size, and crystalline phase composition), which is controlled by the manufacturing technologies. In addition, the true hardness and the biaxial flexural strength of the 3D printed YSZ samples are discussed. At last, the advantages of 3D printing ceramics in dentistry are mentioned.

The structural and optical response of the Au nanoparticles embedded in YSZ modified using high-energetic ion irradiation

Gold nanoparticles (Au NPs) were synthesized in single-crystalline yttria-stabilized zirconia (YSZ) using a high-energetic gold ion implantation with the intention of subsequent modification by silicon ion irradiation. (100)-oriented YSZ samples were implanted with 1 MeV Au+ ions at room temperature and fluences of 1.5×1016 cm−2, 5.0×1016 cm−2 and 7.5×1016 cm−2 and subsequently annealed for 1 h at 1100 °C in air. Gold NPs modification was realized with irradiation by 10 MeV Si3+ with the fluence of 5.0×1014 cm−2. Au NPs distribution and subsequent YSZ structure modification were studied. YSZ samples as-implanted with Au ions, annealed and subsequently irradiated with Si ions were characterized using Rutherford backscattering spectrometry (RBS) and RBS in channelling mode (RBS-C). The RBS spectra show that the implanted Auions concentrate in the YSZ sub-surface layer in the depth of about 50-250 nm and shift to greater depth with increasing ion fluence. The Si3+ ions irradiation slightly increased Zr sub-lattice disorder. Optical absorbance shows an increase of absorption band at 550 nm after Au implantation only for the two highest ion fluences. After annealing and Si irradiation, optical absorbance increased at 530-580 nm with connection to ion implantation fluence of Au+ ions.

Five dimensional grain boundary distribution for yttria stabilized zirconia based on experimentally determined macroscopic boundary parameters

Distributions showing the frequencies of occurrence of grain boundaries as functions of their 5 macroscopic boundary parameters have been computed for a set of yttria-stabilized zirconia samples sintered at different conditions and thus having different grain sizes. For this purpose, datasets containing both grain misorientation and boundary plane parameters have been collected by the means of the 3D EBSD technique. Then, the 5-parameter distributions have been computed using the approach based on kernel density estimation. A few top peaks are visible in all of the obtained distributions. Their heights exceed the level of the random distribution by at least about 3 multiples of the corresponding statistical errors. The list of favored grain boundaries includes the Σ3/(111) and Σ11/(11¯3) boundaries, as well as the boundaries having both the boundary plane (100) and misorientation by 10∘ to 37∘ about the [100] axis.The largest of the collected dataset containing 64,506 distinct grain boundaries, and being probably the largest dataset of this kind ever collected for zirconia, allowed to study e.g. rare boundaries like those with high Σ misorientations about the [110] axis.

Effect of annealing on grain growth and Y segregation behavior in tetragonal ZrO2 thin film

AbstractIn order to fabricate tetragonal yttria stabilized zirconia samples with large grain size, 3 mol% Y2O3 doped zirconia thin films were grown on (0001) α‐Al2O3 substrate by pulsed laser deposition (PLD) followed by subsequent high temperature annealing. The thin film samples were annealed at 1200°C, 1250°C, 1300°C, and 1350°C in order to obtain larger grain size without Y segregation. The microstructure and chemical composition of these annealed films were analyzed using atomic force microscopy, scanning transmission electron microscopy, and energy‐dispersive X‐ray spectroscopy. The as‐grown thin film was found to be composed of [111]‐oriented grains of ∼100 nm connected with small‐angle tilt boundaries. Based on analysis of annealed thin films, it was revealed that grain growth of tetragonal zirconia occurred anisotropically. Cross section scanning transmission electron microscopy observations revealed that such grain growth behavior is affected by the step‐terrace structures of the sapphire substrate. Energy‐dispersive X‐ray spectroscopy showed that Y was found to distribute almost uniformly below 1300°C but to segregate at the grain boundaries at 1350°C. As a conclusion, the 1300°C‐annealed sample shows the largest grain size with homogeneous Y distributions.

Nanoindentation of single-crystal and polycrystalline yttria-stabilized zirconia: A comparative study by experiments and molecular dynamics simulations

A combination of nanoindentation experiments and molecular dynamics (MD) nanoindentation simulations is carried out in this paper to study the mechanical properties and deformation behaviors of single-crystal and polycrystalline yttria-stabilized zirconia (YSZ). Different Young’s moduli are found in the nanoindentation experiments of single-crystal and polycrystalline YSZ samples, though these two YSZ materials almost have the same hardness. In addition, with the aid of atomic force microscopy, different deformation behaviors are observed in single-crystal and polycrystalline YSZ. The different Young’s moduli and deformation behaviors of single-crystal and polycrystalline YSZ observed in experiments are explained by MD simulations. The simulation results show that during the indentation process, the slip occurs inside single-crystal YSZ but along the grain boundaries of polycrystalline YSZ. These different deformation mechanisms between single-crystal and polycrystalline YSZ account for the lager Young’s modulus and more significant pile-up phenomenon observed in single-crystal YSZ. In addition, our MD simulations also reveal that the mechanical properties of YSZ are almost independent of the temperature but can be significantly affected by the number of YSZ grains. Specifically, both the Young’s modulus and hardness of polycrystalline YSZ are found to decrease as the number of grains grows.

Five Dimensional Grain Boundary Distribution for Yttria Stabilized Zirconia Based on Experimentally Determined Macroscopic Boundary Parameters

Distributions showing the frequencies of occurrence of grain boundaries as functions of their 5 macroscopic boundary parameters have been computed for a set of yttria-stabilized zirconia samples sintered at different conditions and thus having different grain sizes. For this purpose, datasets containing both grain misorientation and boundary plane parameters have been collected by the means of the 3D EBSD technique. Then, the 5-parameter distributions have been computed using the approach based on kernel density estimation. A few top peaks are visible in all of the obtained distributions. Their heights exceed the level of the random distribution by at least about 3 multiples of the corresponding statistical errors. The list of favored grain boundaries includes the Σ3/(111) and Σ11/(1‾13) boundaries, as well as the boundaries having both the boundary plane (100) and misorientation by 10° to 37° about the [100] axis.

Sealing of porous YSZ samples with Gd-doped CeO2 film produced using aqueous metal-EDTA complex solution

In this study, we propose a method for sealing porous samples using aqueous solutions of metal-ethylenediaminetetraacetic acid (EDTA) complexes. Gd-doped ceria (GDC) films were synthesized on porous NiO-mixed yttria-stabilized zirconia (YSZ) samples by coating them with a (Ce, Gd)-EDTA complex solution and subsequently sintering them in air at 850 °C for 1 h. When the Ce/Gd ratio in EDTA was 0.8:0.2, only a crystalline Ce0.8Gd0.2O1.9 phase was formed on the surface. The obtained results confirmed that the proposed treatment is effective for sealing the surfaces and open pores of porous samples. Finally, it was observed that a GDC layer was formed both at the sample surface and within the pores smaller than 1.7 μm.

An investigation of corrosive effects on zirconia with different crystal structures.

This study aimed to compare the time-related corrosive resistance in different corrosive solution environments after sintering of zirconia with different crystal structures. The zirconia samples were produced in pellet form as 12.7 × 3 mm. To determine the time-related corrosion resistance of the sintered samples in sodium carbonate (Na2 CO3 ), sodium chloride (NaCl), and citric acid (C6 H8 O7 ) solutions, the weights were measured at baseline then on the first and fifth days and the microhardness values were calculated. For the evaluation of surface appearance, images were obtained with a scanning electron microscope. The baseline microhardness values of the groups with 3 and 10 mol% yttria-stabilized zirconia samples were found to be 1,064 VHN and 1,079 VHN, respectively. The microhardness values of the groups with 3 mol% yttria-stabilized zirconia samples immersed in Na2 CO3 1d (1,010 VHN) and 5d (1,060 VHN), and NaCl (1d (1,010 VHN) and 5d (1,055 VHN) were found to be affected more. The microhardness values of the sample group (1,064 VHN) with 10 mol% yttria doped zirconia which was left for 5 days in citric acid were found to be lower than the sample group (1,120 VHN) with 3 mol% yttria added. C6 H8 O7 was seen to have a greater corrosive effect with increased yttria content and the microhardness value decreased. With longer duration of the samples of all the groups in C6 H8 O7 , NaCl, and Na2 CO3 solutions, the surface characteristics of the samples were affected negatively. With prolonged immersion in the corrosive solutions, the resistance to the corrosion causing the changes in the surface topography of the samples was seen to decrease.

Temperature dependent electrical properties of YSZ synthesized through microwave combustion

In the present work, Yttria Stabilized Zirconia (YSZ) was synthesized rapidly through microwave combustion. Subsequently, the synthesized YSZ was conventional sintered at different temperatures, ranging from 1200 to 1400 oC at 50 °C intervals. X-ray diffraction results confirmed that the synthesized YSZ belongs to the cubic phase. Further, the investigation of microstructures of sintered YSZ using SEM analysis confirmed the temperature dependent grain growth behavior. Among the sintered YSZ, the sample sintered at 1400 oC was found to possess the highest median particle size (4.77 µm), as well as average grain size (4.15 µm) with increased relative density (92%). Impedance studies for the YSZ samples sintered at different temperatures revealed that the conductivity is directly proportional to the relative density and operating temperature. Accordingly, the sample sintered at 1400 °C showed the highest ionic conductivity of 5.68 × 10–2 S/cm at 700 °C. The data resulted from various studies, suggesting that the YSZ synthesized through microwave assisted approach yields conductivity and dielectric behavior similar to conventional methods. Hence, this approach could also be extended to the synthesis of various electrolyte materials (E.g., LSDF, LSCO, and BSCF) that can be used in solid oxide fuel cells at a low cost and in a short duration.

CMAS corrosion of YSZ thermal barrier coatings obtained by different thermal spray processes

Degradation of yttria-stabilized zirconia (YSZ) layers by molten CaO-MgO-Al2O3-SiO2 (CMAS)-based deposits is an important failure mode of thermal barrier coating (TBC) systems in modern gas turbines. The present work aimed to understand how the chemical purity and microstructure of plasma-sprayed YSZ layers affect their response to CMAS corrosion. To this end, isothermal corrosion tests (1 h at 1250 °C) were performed on four different kinds of YSZ coatings: atmospheric plasma-sprayed (APS) layers obtained from standard- and high-purity feedstock powders, a dense – vertically cracked (DVC) layer, and a suspension plasma sprayed (SPS) one. Characterization of corroded and non-corroded samples by FEG-SEM, EBSD and micro-Raman spectroscopy techniques reveals that, whilst all YSZ samples suffered grain-boundary corrosion by molten CMAS, its extent could vary considerably. High chemical purity limits the extent of grain-boundary dissolution by molten CMAS, whereas high porosity and/or fine crystalline grain structure lead to more severe degradation.

Comparative Study of Yttria-Stabilized Zirconia Synthesis by Co-Precipitation and Solvothermal Methods

Yttria-stabilized zirconia (YSZ) at 8 mol.% is the most commonly used electrolyte material in the solid oxide fuel cell field. In this study, co-precipitation and solvothermal methods are used to synthesize nanocrystalline yttria-stabilized zirconia. The effects of the synthesis condition (calcination temperature) and different methods on the crystal phase, the microstructure and the electrical performance of YSZ are comparatively investigated and analyzed in detail. X-ray diffraction results reveal that both the co-precipitation and solvothermal methods can be used to successfully synthesize nano-YSZ ceramic powders with a pure crystal phase of fluorite cubic structure. The grain sizes of the YSZ samples prepared by these two methods are both smaller than that of the commercial Tosoh YSZ, with the sample from the solvothermal method revealing the smallest grain size. The electrochemical impedance spectra demonstrate that the YSZ prepared by co-precipitation with 500°C calcination reveals the smallest ohmic resistance among different calcination temperatures. It also shows a relatively lower ohmic resistance of 2.04 Ω cm2, while the YSZ sample synthesized by the solvothermal method has a higher ohmic resistance of 8.89 Ω cm2, with corresponding ionic conductivities of 0.0266 S cm−1 and 0.00562 S cm−1, respectively.

Sintered Tape-cast 3YSZ Supports Human Bone Marrow Derived Stem Cell Osteogenic Differentiation

ABSTRACTSintered tape-cast yttria-stabilized zirconia (YSZ) was evaluated for its elemental composition, crystal structure, and imaged with atomic force microscopy (AFM) and scanning electron microscopy (SEM). Human bone marrow stem cells (hBMSC) were cultured on the ceramic and differentiated into the osteoblast lineage; alkaline phosphatase (ALP) activity was tracked as a differentiation marker. The YSZ was composed of purely tetragonal grains with a median equivalent circular diameter of 283 nm. Zirconium, yttrium, oxygen, and adventitious carbon was detected on the substrate with no other elements in significant quantities detected. YSZ samples had an RMS roughness value of 27 nm, elastic modulus of 206 ± 14 GPa, and hardness of 14 ± 2 GPa. hBMSC were observed to attach and proliferate on the YSZ surfaces and had significantly increased ALP versus the undifferentiated control cultured on glass. This method for producing a YSZ ceramic yields a typical material of this type and supports attachment and differentiation of hBMSC; thus, making it useful as a bone implant material.

Selective laser melting of yttria-stabilized zirconia

The mechanism of phase transformation and microstructure of yttria-stabilized zirconia (YSZ), prepared by selective laser melting (SLM) at a laser wavelength of 1 μm, has been investigated. Also, the effect of different working gases and heat treatment has been studied. Experimental results present that processing parameters can be optimized and determined by Liner Energy Density. X-ray diffraction analysis confirmed the absence of monoclinic phase under argon flow during SLM, with gray-color appearance due to the lack of oxygen, which impedes the transformation from tetragonal to monoclinic phase partially. Later, the color becomes white during heat treatment because samples are exposed to the air with sufficient amount of the oxygen and the diffraction peaks of monoclinic phase increased. When SLM and heat treatment was carried out in the air, the YSZ samples appeared in white-color, which indicates the presence of both monoclinic and tetragonal phase. The morphology and microstructure showed there occurred bonding phenomenons among particles, only surface partially melted between particles with weak bonding strength. The top surface morphology of air-prepared sample showed cracks, un-melting particles and cave-like pores because of uneven distribution of temperature variations. This paper also made a preliminary research and provided a feasibility method to melt zirconia ceramics completely, in which more energy input by multi-scanning in the air working gas.