Effect of RF power on the properties of transparent conducting zirconium-doped zinc oxide films prepared by RF magnetron sputtering

Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency （RF） msgnetron sputtering at room temperature, The RF power is varied from 75 to 150 W. At first the crystallinity and conductivity of the film are improved and then both of them show deterioration with the increase of the RF power, The lowest resistivity achieved is 2.07 × 10^-3Ωcm at an RF power of 100W with a Hall mobility of 16cm^2V^-1s^-1 and a carrier concentration of 1.95 × 10^20 cm^-3. The films obtained are polycryetalline with a hexagonal structure and a preferred orientation along the c-axis, All the films have a high transmittance of approximately 92% in the visible range. The optical band gap is about 3.33 eV for the films deposited at different RF powers.

Properties of hydrogen permeation barrier on the surface of zirconium hydride

A hydrogen permeation barrier was manufactured by the in situ reaction of zirconium hydride with oxygen. A reduction in the hydrogen permeation of the oxide films was detected by measuring the mass difference of the zirconium hydride samples after the dehydrogenation experiment. The reaction of zirconium hydride with oxygen occurs only under the condition that the temperature is higher than 673 K in the oxygen partial pressure of 0.1 MPa. The oxide film is composed of two layers, a permeable oxide layer and a dense oxide layer, and the main phase of the oxide film is ZrO2 with baddeleyite structure. The XPS analysis shows that O-H bonds exist in the oxide film, which are helpful for resisting hydrogen diffusion through the oxide film.

Study on Corrosion Resistance of N36 Zirconium Alloy in LiOH Aqueous Solution

Zr-Sn-Nb-Fe alloys are one of the important directions for continuous improvement of zirconium alloys for high burn-up fuel assemblies. The corrosion resistance of Zr-Sn-Nb-Fe alloys is closely related to the alloying element and water chemical condition. To better understand the effect of Sn on corrosion resistance of Zr-Sn-Nb-Fe alloy, the normal N36 (Zr-1Sn-1Nb-0.3Fe) and low-tin N36 (Zr-0.8Sn-1Nb-0.3Fe) alloy sheets were prepared and tested in static autoclave in both of 0.01 mol/L LiOH and 0.03 mol/L LiOH aqueous solution at 360°C and 18.6 MPa. The characteristics of the microstructure and oxide film of alloys were analyzed by TEM and SEM respectively. It was shown that that the corrosion transition of the normal N36 appears earlier and the weight gain is higher than the low-tin N36 in two corrosive mediums. The cracks paralleling to the interface of oxide/metal are formed in the fracture surface of the oxide film and the micrographs at the oxide film/substrate interface appear uneven morphology. With the increasing of corrosion gain, there are more parallel cracks in oxide film and the uneven morphology at the oxide film/substrate interface is more obvious.

Optimization of ferroelectricity and endurance of hafnium zirconium oxide thin films by controlling element inhomogeneity

Ferroelectric thin films based on HfO_(2) have garnered increasing attention worldwide,primarily due to their remarkable compatibility with silicon and scalability,in contrast to traditional perovskite-structured ferroelectric materials.Nonetheless,significant challenges remain in their widespread commercial utilization,particularly concerning their notable wake-up effect and limited endurance.To address these challenges,we propose a novel strategy involving the inhomogeneous distribution of Hf/Zr elements within thin films and explore its effects on the ferroelectricity and endurance of Hf_(0.5)Zr_(0.5)O_(2) thin films.Through techniques such as grazing incidence X-ray diffraction,transmission electron microscopy,and piezoresponse force microscopy,we investigated the structural characteristics and domain switching behaviors of these materials.The experimental results indicate that the inhomogeneous distribution of Hf/Zr contributes to improving the frequency stability and endurance while maintaining a large remnant polarization in Hf_(0.5)Zr_(0.5)O_(2) ferroelectric thin films.By adjusting the distribution of Zr/Hf within the Hf_(0.5)Zr_(0.5)O_(2) thin films,significant enhancements in the remnant polarization(2P_(r)>35μC/cm2)and endurance(>109)along with a reduced coercive voltage can be achieved.Additionally,the fabricated ferroelectric thin films also exhibit high dielectric tunability(≥26%)under a low operating voltage of 2.5 V,whether in the wake-up state or not.This study offers a promising approach to optimize both the ferroelectricity and endurance of HfO_(2)-based thin films.

Effect of dissolved oxygen on corrosion behavior of Zr-0.85Sn-0.16Nb-0.37Fe-0.18Cr alloy in 500℃ and 10.3 MPa super-heated steam

To better understand the role of dissolved oxygen(DO) in affecting corrosion behavior of zirconium alloys,the Zr-0.85 Sn-0.16 Nb-0.37 Fe-0.18 Cr(wt.%) alloy was corroded in super-heated steam at 500℃ and 10.3 MPa under 1×10-6 DO and deaeration conditions.The microstructure of the alloy and oxide films was investigated by SEM,TEM,EDS and EBSD.Results show that the corrosion is aggravated under 1×10-6 DO.Compared with the deaeration condition,the oxide film is looser,and has more micro-cracks and more uneven inner surface under DO condition.For the oxide film forming under deaeration condition,the selected area diffraction(SAED) spots of planes(002)m,■ and(101)t are strong,while those of the(001)m and■ are weak.However,for the oxide film forming under DO condition,the SAED spots of planes(111)m,(200)m and(101)t are strong,while those of the(100)m and(110)m are weak.The higher DO content in super-heated steam accelerates the growth of oxide films,thus decreasing the corrosion resistance of zirconium alloys.

Influence of the sputtering pressure on the properties of transparent conducting zirconium-doped zinc oxide films prepared by RF magnetron sputtering

Transparent conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared on water-cooled glass substrate by radio frequency magnetron sputtering at room temperature. The Ar sputtering pressure was varied from 0.5 to 3 Pa. The crystallinity increases and the electrical resistivity decreases when the sputtering pressure increases from 0.5 to 2.5 Pa. The cystallinity decreases and the electrical resistivity increases when the sputtering pressure increases from 2.5 to 3 Pa. When the sputtering pressure is 2.5 Pa, it is obtained that the lowest resistivity is 2.03 x 10^-3Ω .cm with a very high transmittance of above 94%. The deposited films are polycrystalline with a hexagonal structure and a preferred orientation perpendicular to the substrate.

Investigation of potential interferences on the measurement of dissolved reactive phosphate using zirconium oxide-based DGT technique

A diffusive gradients in thin films （DGT） technique based on hydrous zirconium oxide （Zr-oxide） has been recently developed for the measurement of dissolved reactive phosphate （DRP）. In this study, the detailed performance of the DGT technique is reported. Spiking experiments revealed that several orthophosphate monoester compounds contributed to the Zr-oxide DGT measurements of DRP. However, such a phenomenon is unlikely to occur during field conditions due to the low concentration of organic P in typical natural waters. The presence of Cl- （up to 106 g/L）, SO42- （up to 16 g/L）, HCO3- （up to 817 g/L）, and AsO2- and AsO 3 4 （both up to 1 mg As/L） in solutions had negligible effects on the measurement of DRP. The threshold concentrations of Cl-, SO42- and HCO3- have been increased from previous reports for the measurements of DRP using other adsorbent-based DGT techniques. The capacity for DGT measurements of DRP decreased with increasing solution pH （4.2-9.2）. The lowest capacity （95 μg P/m2 at pH 9.2） was still greater than that of other DGT techniques that are usually used for the measurement of DRP （2-12 μg P/cm2 ）. The Zr-oxide binding gel could be stored for up to 2 years without any aging effect. This period of validity was considerably longer than the ferrihydrite binding gel that is commonly used in present DGT devices （6 months）. The field application revealed that the concentrations of DRP measured in three fresh water samples using the Zr-oxide DGT technique were in agreement with those of the traditional colorimetric method.

Al掺杂浓度对Hf0.5Zr0.5O2薄膜铁电性能的影响

采用脉冲激光沉积法(Pulsed laser deposition,PLD)在Pt/Ti/SiO 2/Si衬底上制备TiN/Al掺杂Hf0.5Zr0.5O2/TiN的MIM(金属-绝缘体-金属)结构薄膜电容器。对Al掺杂浓度为0%~4%(摩尔分数)的Al∶Hf0.5Zr0.5O2薄膜的微观结构以及电学性能进行了研究,在此基础上,还研究了退火温度对Al∶Hf0.5Zr0.5O2薄膜的影响。测试结果表明,随着Al掺杂浓度的增大和退火温度的降低,四方相更加稳定,电滞回线更加细窄,剩余极化强度减小。退火温度为500℃时,掺杂浓度为1.03%(摩尔分数)的Al∶Hf0.5Zr0.5O2薄膜中将诱导出类似反铁电薄膜具有的双电滞回线特性,储能密度更高。分析结果表明,这些变化均是由于Al∶Hf0.5Zr0.5O2薄膜内四方相与正交相之间发生的场致可逆相变以及氧空位的再分布。

Ultraviolet Photoelectric Effect in ZrO2 Single Crystals

Nanosecond photoelectric effect is observed in a ZrO2 single crystal at ambient temperature for the first time. The rise time is 20ns and the full width at half maximum is about 30ns for the photovoltaic pulse when the wafer surface of the ZrO2 single crystal is irradiated by 248 nm KrF laser pulses. The experimental results show that ZrO2 single crystals may be a potential candidate in UV photodetectors.

无铬封闭处理对ZL101A铝合金阳极氧化膜耐蚀性能的影响

对汽车用ZL101A铝合金进行阳极氧化,并分别采用热水封闭、钴盐封闭、锆盐封闭和铈盐封闭等无铬封闭工艺对阳极氧化膜进行封闭处理。表征了封闭前后阳极氧化膜的形貌,并测试分析了封闭前后阳极氧化膜的厚度和耐蚀性能。结果表明:与未封闭阳极氧化膜相比,封闭处理后阳极氧化膜的孔隙率降低,表面平整度和致密性改善,耐蚀性能有不同程度提高,但厚度变化不大。铈盐封闭阳极氧化膜表面平整度和致密性最好,粗糙度为0.216μm,电荷转移电阻达到1.93×10^(5)Ω·cm^(2),腐蚀质量损失为1.79 g/m^(2),其耐蚀性能优于热水封闭、钴盐封闭和锆盐封闭阳极氧化膜。铈盐封闭是效果最好的无铬封闭工艺。

核用锆合金管氧化过程中光谱发射率特性研究

发射率在锆合金管非接触测温的准确性和失水事故情况下的传热分析上具有重要意义。本文采集了SZA4、SZA6和ZIRLO 3种锆合金在400,500,600℃下氧化100min过程中4~12μm内的光谱发射率数据,分析了温度、氧化膜厚度和合金组分对材料光谱发射率特性的影响规律。结果表明,3种锆合金在氧化过程中发射率变化趋势基本相同,但组分差异导致在发射率的数值和振荡特性上略有差别。通过建立薄膜干涉模型,解释了光谱发射率在波长方向上的振荡现象,并结合振荡极值与干涉效应原理计算了合金表面氧化膜厚度,在0.6~8μm范围内测量精度达到±0.3μm。

锆合金氧化膜及基体中氧的扩散

锆合金氧化膜及基体中氧的扩散系数是锆合金腐蚀动力学中的重要参数,目前文献报道的氧在锆及氧化膜中的扩散系数数值差异较大。本文通过真空退火试验,得到不同温度下氧化膜中氧浓度分布,计算了氧在锆合金基体中的扩散系数;通过氧化膜的等效扩散模型,由腐蚀转折前的腐蚀增重曲线,估算锆合金氧化膜中氧的扩散系数,得到Zr-Sn-Nb合金基体中氧的扩散系数随温度的变化规律为D_(Zr)(cm^(2)/s)=0.18exp(-180 000/RT);通过转折前的腐蚀增重曲线,估算得到氧化膜中氧的扩散系数随温度的变化规律为D_(ox)(cm^(2)/s)=3×10^(-7)exp(-101 550/RT)。

Thickness dependence of the properties of transparent conducting ZnO:Zr films deposited on flexible substrates by RF magnetron sputtering

Transparent conducting zirconium-doped zinc oxide （ZnO：Zr） thin films with high transparency, low resistivity and good adhesion were successfully prepared on water-cooled flexible substrates （polyethylene glycol terephthalate, PET） by RF magnetron sputtering. The structural, electrical and optical properties of the films were studied for different thicknesses in detail. X-ray diffraction （XRD） and scanning electron microscopy （SEM） revealed that all the deposited films are polycrystalline with a hexagonal structure and a preferred orientation perpendicular to the substrate. The lowest resistivity achieved is 1.55 × 10-3 Ω·cm for a thickness of 189 nm with a Hall mobility of 17.6 cm2/（V·s） and a carrier concentration of 2.15×1020 cm-3. All the films present a high transmittance of above 90% in the wavelength range of the visible spectrum.

关于M5合金燃料包壳表面材料在堆内流致振动下脱落共性问题的研究

M5锆合金包壳是由法国法马通公司设计研发的,目前广泛应用于核电厂AFA-3G等系列的燃料组件。本文分析了国内外核电厂使用M5合金燃料包壳表面材料在堆内流致振动下脱落共性问题的研究现状,包括燃料组件外观检查情况、氧化膜厚度测量情况等,从而得出研究结论并提出合理建议。

水中溶解氧对低锡中铌锆合金氧化膜显微组织和电化学性能的影响

在含溶解氧(质量浓度分别为300,1 000μg·L^(-1))环境中对Zr-0.4Sn-0.7Nb-0.3Fe-0.1Cr-0.15Mo-0.12O新型低锡中铌锆合金进行了长达300 d的堆外高压釜腐蚀试验,研究了腐蚀过程中合金表面氧化膜微观结构的变化,并结合离位电化学检测表征了腐蚀后合金的电化学性能,分析了溶解氧对电化学性能的影响。结果表明:在含溶解氧环境中腐蚀时,合金表面氧化膜的厚度随时间呈线性增加,氧化膜内裂纹增多,氧化膜/基体界面起伏加剧;当溶解氧含量较高时,合金的腐蚀质量增加较大,表面氧化膜内裂纹较多。在含溶解氧环境中腐蚀130 d时,合金的自腐蚀电位和极化电阻最小,自腐蚀电流密度最大,其耐腐蚀性不仅与表面氧化膜厚度有关,还受氧化膜内缺陷影响;腐蚀300 d时,合金的阻抗谱呈多容抗弧特征,较高溶解氧含量下的容抗弧数量较多。

水化学及合金成分对锆合金腐蚀时氧化膜显微组织演化的影响

将Zr-4和成分接近ZIRLO的3#合金样品置于高压釜中,经过360℃,18.6MPa的0.01mol/LLiOH水溶液腐蚀150d后,增重分别达到310mg/dm2和82mg/dm2,3#合金的耐腐蚀性能明显优于Zr-4。用透射电镜、扫描电镜和扫描探针显微镜研究了两种样品经过70d和150d腐蚀后,氧化膜不同深度处的显微组织和晶体结构;研究了氧化膜的断口形貌和氧化膜的表面形貌。结果表明:Zr-4氧化膜中的空位比3#合金氧化膜中的更容易通过扩散凝聚形成孔洞簇和晶界微裂纹,也容易发展成平行于氧化膜/金属界面的裂纹,导致腐蚀转折提早发生,这与Li+和OH-渗入氧化膜后降低氧化锆表面自由能的程度有关。从氧化膜表面晶粒形貌判断,Zr-4样品形成氧化锆后的表面自由能比3#合金样品形成氧化锆后的低,这是合金成分不同引起的一种差异,也可能是Zr-4样品在LiOH水溶液中的耐腐蚀性能比3#样品差的一个重要原因。

水化学对锆合金耐腐蚀性能影响的研究

经对包括 Zr- 4在内的 4种不同成分锆合金耐腐蚀性能的研究发现：高温水中添加了 0.01～ 0.1molLiOH后，腐蚀转折提早发生，转折后的腐蚀速率增加。这种现象随 LiOH浓度增大变得更加显著，但在成分不同的锆合金中有明显的差异，同时添加 H3BO3后又可以抑制 LiOH的加速腐蚀作用。氧化膜显微组织的观察结果表明：转折后的加速腐蚀过程与氧化膜中孔洞簇的出现有关，添加 LiOH以及改变合金成分后，通过影响孔洞簇的形成而对腐蚀转折及转折后的腐蚀加速产生作用。从分析氧化膜中 Li＋的浓度及有关腐蚀增重的结果来看，似乎 Nb可以部分抑制 Li＋进入氧化膜，而足够含量的 Sn可以缓解 Li＋的有害作用。因此，只有 Sn和 Nb含量都比较高的 3样品，在含 LiOH介质中的耐腐蚀性能最好，而含 Sn和 Nb较低的锆合金样品，在这种条件下的耐腐蚀性能还不如 Zr- 4。这些锆合金在不含 LiOH的 400℃过热蒸汽中腐蚀时，表现出耐腐蚀性能的变化规律，与含 LiOH高温水中的正好相反，说明了这两种条件下影响腐蚀性能的主导因素有着明显的不同。在靠近氧化膜 /金属界面处的氧化膜，无论在转折前或转折后，都存在亚稳的非晶、立方和四方结构的 ZrO2，没有观察到孔洞，在氧化膜中间层和表层已生成孔洞处，是单一的单斜结构 ZrO2，

新锆合金氧化膜微观组织结构的研究

研究了氧化膜的微观组织结构,研究结果表明,对采用不同热处理的两种新锆合金,无论从内到外,氧化膜结构均极为相似;不同热处理对氧化膜结构影响在于是否有第二相易于嵌入ZrO2中,累计退火参数值越高,嵌入可能性大;该嵌入的沉淀相促进氧化膜从其它结构到单斜结构的转变,残留于原金属晶界处的第二相促使晶界开裂。靠近氧化膜金属基体氧化膜内表面观察表明,氧化膜生长是不均匀的,呈菜花状;腐蚀速率越高,菜花尺寸越大,凸起越严重。本研究说明,采用低温加工工艺获得尺寸较小的沉淀相是合金耐蚀性能改善的基本途径。

锆合金耐蚀性能影响因素概述

锆合金作为燃料包壳材料广泛应用于轻水反应堆。导致其在服役过程中腐蚀的因素复杂多样,随着合金成分、氧化物类型、第二相、晶粒形貌以及工作介质等的不同,其耐蚀性能会发生显著变化,分别介绍了这些因素对锆合金包壳腐蚀行为的影响。

水化学和腐蚀温度对锆合金氧化膜中压应力的影响

在不同水化学条件下,对Zr-4和N18管状样品进行腐蚀实验,然后用氧化膜卷曲法测量腐蚀样品氧化膜中的压应力,研究腐蚀温度、水化学对氧化膜中压应力随厚度变化的影响规律.实验结果表明,Zr-4和N18样品氧化膜中的压应力均按360℃去离子水>400℃过热蒸汽>360℃L iOH水溶液的顺序依次减小.在360℃L iOH水溶液中腐蚀时,氧化膜中的压应力最低,这与L i+和OH-会渗入氧化膜,降低氧化锆表面自由能,从而加速氧化膜中空位的扩散凝聚、孔隙的形成和微裂纹发展的过程有关.高温使空位的扩散加快,促进了氧化膜中压应力的弛豫过程.