退火处理对不同RF功率下制备ZnO薄膜的结晶性能的影响

采用RF磁控溅射法,在不同溅射功率下在玻璃衬底上制备了ZnO薄膜,并对所制备的ZnO薄膜在空气气氛中进行了不同温度（350-600℃）的退火处理.利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）等研究了退火对不同溅射功率条件下制备的ZnO薄膜晶体性能和应力状态的影响.研究表明,在衬底没有预热的情况下,较低功率（190W）下制备的ZnO薄膜,当退火温度为500℃时,能获得单一c轴择优取向和最小半高宽,张应力在350℃退火时最小;较高功率（270W）下,薄膜最佳c轴取向和晶粒度在600℃退火温度获得,张应力最小的退火温度在350-500℃之间.当衬底预热至300℃时,退火处理对两种功率下制备的薄膜的结晶性能和应力的影响基本一致.     

立方氮化硼薄膜及溅射沉积的研究进展

溅射沉积由于获得的cBN薄膜颗粒尺寸小、立方相含量高,是cBN薄膜制备技术发展的一个重要方向。本文介绍了溅射沉积过程中的基体负偏压、沉积气氛、沉积温度、靶材功率等工艺参数对cBN薄膜中立方相的含量和薄膜性能的影响规律。并从优化沉积工艺参数、采用过渡层及在膜层中引入其它元素方面介绍了在降低膜层应力方面取得的研究进展。分析归纳出溅射沉积cBN薄膜目前存在的主要问题是薄膜应力过大、存在非立方相氮化硼及B、N原子的比例失配。提出了下一步研究工作的重点是通过深入认识溅射沉积cBN薄膜的的形成机理,优化沉积工艺参数及设计合理的过渡层和新型梯度涂层,以提高立方相的含量、保证B、N原子的比例、降低膜层应力。     

铝薄膜对烧结NdFeB磁体耐蚀性能的影响

采用直流磁控溅射的方法在烧结NdFeB磁体表面沉积Al薄膜提高磁体的耐蚀性能。研究膜厚及溅射功率对薄膜结构和耐蚀性能的影响。利用SEM对Al薄膜的微观结构进行分析,并采用动态极化曲线和中性盐雾实验分析Al薄膜耐蚀性能。均匀致密的Al薄膜的形成是获得良好耐蚀性能的必要条件。在51-82 W溅射功率下制备的6.69μm的Al薄膜具有良好的耐蚀性能。     

溅射功率对不锈钢衬底ZnO∶Al薄膜性能的影响

采用直流磁控溅射技术,以掺Al为2%的Zn O陶瓷靶为靶材,通用的304不锈钢为衬底,制备了一系列Zn O∶Al薄膜,研究了溅射功率对样品薄膜结构和表面形貌、光学特性的影响。结果表明:制备的薄膜都为六方纤锌矿结构,并有高度的c轴择优取向;溅射功率对薄膜的性能有显著的影响,即随着溅射功率的增大,从35 W到80 W,晶粒尺寸先增大后减小,薄膜表面陷光结构先变好后变坏,最优值出现在溅射功率为65 W时,此时薄膜对波长小于360 nm的光吸收率约为91%。     

磁控溅射技术制备二氧化钛薄膜研究进展

磁控溅射技术具有溅射速率高、膜基结合力好、易实现工业化生产等技术优势,在二氧化钛薄膜制备方面具有显著优势,但磁控溅射参数对二氧化钛薄膜结构和性能的影响显著,如何通过控制和优化磁控溅射参数,获得高性能二氧化钛薄膜已成为目前的研究热点。概述了不同晶型二氧化钛的结构特点、物理性质和磁控溅射制备二氧化钛薄膜的工作原理,指出成膜过程中的溅射功率、溅射气压、溅射时间、沉积温度和氧分压等是影响薄膜结构和性能的主要因素,并详细阐述了上述五种工艺参数对二氧化钛薄膜沉积速率、膜层厚度、表面粗糙度、相组成和光催化性能等的影响规律和作用机制。此外,还对其他影响薄膜结构和性能的关键因素及影响规律进行了介绍,包括退火温度对膜层组织转变影响的规律,金属元素掺杂和非金属元素掺杂对膜层形貌和性能的影响,以及不同溅射靶材特点及其对成膜过程的影响。最后提出未来磁控溅射技术制备二氧化钛薄膜的研究难点,并对二氧化钛薄膜的下一步研究方向进行了展望。     

直流磁控溅射法在玻璃上沉积金属镍膜的研究

采用直流磁控溅射法,在玻璃基板上制备了用于显示器视窗保护玻璃的半透明镍膜,测定了不同溅射条件下所得镍膜的表面粗糙度、透过率及厚度,讨论了溅射气压、溅射功率、行车速度等对薄膜性能的影响。结果表明,薄膜的表面粗糙度随溅射功率的增加而增大,控制溅射气压、溅射功率和行车速度为一定值,可以得到透过率为50%的半透镍膜。     

磁控溅射工艺对FeCrCoNiMn氧化物薄膜质量的影响

目的 探究氧气浓度、基底温度和溅射功率对高熵合金氧化物薄膜成分、膜基结合力和硬度的影响,分别找出某一工艺参数的改变对性能的影响趋势,并总结影响因素和规律。方法 采用射频磁控溅射方法在Si(100)基体上制备不同工艺参数下的(FeCrCoNiMn)Ox薄膜,结合X射线衍射仪(XRD)、能谱仪(EDS)、划痕仪、纳米压痕仪分析薄膜的物相结构、成分组成、膜基结合力、硬度和弹性模量。结果 薄膜为FCC结构。膜基结合力、硬度和弹性模量随着氧气浓度的增加,分别由4.85 N、6.06 GPa、137.8 GPa提高至6.56 N、14.51 GPa、189.4 GPa,最后降至3.75 N、7.52 GPa、144.9 GPa。薄膜的膜基结合力、硬度和弹性模量随着基底温度的升高而升高,分别由3.6 N、12.58 GPa、164.2 GPa升高到5.05 N、14.51 GPa、189.4 GPa。随着溅射功率的提高,膜基结合力由5.05 N提高至8.25 N,硬度和弹性模量呈先升高后降低的趋势。结论 与普通FeCrCoNiMn合金薄膜相比,氧原子的引入使(FeCrCoNiMn)Ox薄膜拥有更大的混合熵,增强了其固溶强化效应。氧气浓度和溅射功率对薄膜成分的影响较大,基底温度对成分无明显影响。适当提高氧气浓度和溅射功率可以有效提高薄膜的力学性能,在温度为350 ℃时膜基结合力和硬度均最好。     

Zn靶与掺铝ZnO靶共溅射制备ZnO:Al薄膜及其性能

采用Zn靶和ZnO(掺2%Al2O3(质量分数))陶瓷靶在玻璃衬底上共溅射沉积Al掺杂ZnO薄膜,即ZnO:Al透明导电薄膜,研究Zn靶溅射功率(0～90 W)和衬底温度(室温、100℃和200℃)对薄膜结构、形貌、光学和电学性能的影响。结果表明:按双靶共溅射工艺制备的ZnO:Al薄膜的晶体结构均为六角纤锌矿结构,且随着Zn靶溅射功率的增加,薄膜的结晶质量呈现出先改善后变差的规律,薄膜中的载流子浓度逐渐升高,电阻率逐渐降低,而薄膜的光学性能受其影响不大;随着衬底温度的升高,薄膜的结晶性能得到改善,薄膜的可见光透过率增强,电阻率降低。     

共溅射法制备AZO薄膜及其光电性能的研究

目的研究Al靶直流溅射功率对Al掺杂ZnO(AZO)薄膜光电性能的影响。方法以金属Al和ZnO陶瓷作为靶材,采用直流与射频双靶磁控共溅射的方法,在玻璃基片上制备AZO薄膜。通过改变Al靶直流溅射功率,获得不同的薄膜。采用X射线衍射仪(XRD)、光电子能谱仪(XPS)、原子力显微镜(AFM)、紫外-可见分光光度计(UV-Vis)、四探针测试仪,对薄膜的微观形貌结构及光电性能进行表征和分析。结果所制备的AZO薄膜均具有C轴取向生长的六角纤锌矿结构,在可见光区域平均透过率超过90%,AZO薄膜的吸收边相比于ZnO薄膜出现了蓝移。当Al靶溅射功率为18 W时,AZO薄膜的最低电阻率为2.49×10~(-3)?·cm,品质因子为370.2 S/cm。结论 Al直流溅射功率对AZO薄膜光电性能的影响较大,溅射功率为18 W时,制备的AZO薄膜性能最优。     

溅射参数对钛膜结构及其TiO_2纳米管制备的影响

采用射频磁控溅射在玻璃基片上制备了参数不同的钛膜,并选取钛膜在HF水溶液中恒压阳极氧化得到TiO2纳米管阵列。结果表明：溅射压强从0．1Pa升至1．5Pa,薄膜致密度显著下降,溅射压强以0．5Pa为宜;溅射功率为105W,溅射速率约为0．23nm／s,溅射时间延长,薄膜厚度线性增加;衬底预热有利于提高膜的致密度和结晶性能,在衬底温度低于300℃时,钛晶粒在（002）晶面择优生长,当升温到更高温度时,（010）峰、（011）峰出现且强度升高,而（002）峰的强度降低;在室温下,当溅射功率小于150W时,薄膜具有较高密度,晶粒生长各向异性,增至167W时,钛晶粒在（002）晶面择优生长,呈明显柱状六方晶表面形态,且晶界有明显孔洞存在,致密度下降。将溅射功率为150W,工作压力为0．5Pa,溅射时间为1h条件下所制备的钛膜在氧化电压为10V、电解液为0．5％（质量分数,下同）HF水溶液中室温阳极氧化,得到高规整度的TiO2纳米管阵列。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

电化学噪声数据处理方法概述

综述了常见的电化学噪声数据处理方法,介绍了直流趋势剔除、统计分析、快速傅立叶变换(FFT)法计算功率谱密度(PSD)以及小波变换处理电化学噪声信号的基本过程,并阐释了各种数学处理及所得参数的物理意义。