层状复合基体材料电极的性能研究

利用Ti-Al、Ti-Cu层状复合材料替代传统钛电极单一钛基体,对比研究其涂层电极与传统钛涂层电极的电化学性能差异,进行电极基体材料的导电性测试、涂层表面的微观形貌观察和线性伏安曲线(LSV)、循环伏安曲线(CV)等电化学分析.结果表明:采用钛-铝、钛-铜复合材料对基体材料进行改进,提高了电极的导电性,并有效地提高了极板的电化学性.     

IrO_2/多孔钛电极的制备及其电化学性能的研究

采用刷涂-热分解的方法在多孔钛基体上获得了纳米线阵列的IrO2涂层电极。FESEM和XRD表征研究表明,在多孔钛基体表面上的IrO2涂层绝大多数为IrO2纳米线,其中纳米线的直径在50 nm左右;而在多孔钛基体截面上的涂层,全部由纳米线阵列组成,纳米线的直径与表面上的相差不大。在多孔钛基体上所获得的IrO2纳米线阵列涂层,活性氧化物的表面积有极大的提高,使其与氧气的接触面积有显著增大,因此循环伏安测试获得了很明显的氧化还原峰。强化寿命测试发现,IrO2/多孔钛电极的寿命为42天。电分析测试表明,IrO2纳米线阵列涂层电极的电流效率可达95%以上。     

钛基体渗碳改性对钛阳极组织与性能的影响

将钛基材在700~1000℃进行渗碳处理后利用热分解法制备了30%RuO2-70%TiO2涂层电极。采用X射线衍射、扫描电镜分析观察渗碳温度对钛基体和涂层组织结构的影响,并通过循环伏安和强化寿命研究了电极的电化学活性和稳定性。结果表明,随着渗碳处理温度的升高,钛基体表面的组织结构发生变化,从而改变了涂层的微观结构,也显著影响了电极的电催化活性和耐蚀性。     

TiN基体氧化物涂层电极材料的制备工艺和性能

利用热分解法制备TiN基体的(Ru,Ti)氧化物涂层,通过OM、XRD、电化学工作站等测试手段对样品的性能和结构进行测试。结果表明涂层具有非连续状裂纹结构,热分解温度对涂层的表面形貌和电催化活性影响很大。在热分解温度为450 ℃,所制备的TiN基体电极电催化析氯性能优于传统钛基体电极。选用TiN基体电极,可以避免基体和涂层间生成TiO₂电阻膜,延长电极的使用寿命,同时由于其内阻小,可以起到降低析氯电位,提高电极的催化活性和节能降耗作用。     

稀土La对RuO_2-TiO_2涂层钛阳极表面结构和性能的影响

以热分解法制备Ru-Ti氧化物涂层钛阳极为基础,在涂层中添加了La元素,观察并研究其对钛基涂层电极结构及其性能的影响。利用SEM、XRD、电化学工作站等分析测试手段,对所制备出的涂层钛电极的表面形貌和性能进行表征。结果表明,在反应温度为450℃、涂层生成物含La量为1.875%时,可以明显改善钛基涂层电极的表面形貌与组织,达到细化晶粒的效果;在电化学性能方面,相比不含La的纯钛基体电极,La元素的掺入可以有效提高电极催化活性,达到节能降耗的目的。     

一种钛基体表面高温抗氧化复合涂层的制备方法

申请号：201510125694．6申请151：2015-03-21公开（公告）日：2017-05-31公开（公告）号：CN104674218B申请（专利权）人：西北有色金属研究院 摘要：本发明公开了一种钛基体表面高温抗氧化复合涂层的制备方法，该方法为：①对钛基体进行表面抛光处理，然后对表面抛光处理后的钛基体进行氧化，得到表面具有二氧化钛陶瓷层的钛基体，再在所述二氧化钛陶瓷层上沉秋金属铝，得到表面具有二氧化钛陶瓷层和铝涂层的钛基体。     

不同酸处理对钛基体性能的影响

本研究在保持酸度和温度一致的条件下分别用草酸、硫酸及盐酸对TA2钛基体进行刻蚀处理,研究不同种类酸处理对钛基体及后续电极性能的影响。研究表明:钛基体在草酸和硫酸中的质量损失率要大于在盐酸中的损失率。金相及SEM观察表明:草酸对钛基体刻蚀效果最好,刻痕细致均匀。强化寿命测试结果显示:经草酸处理后的Sn-Sb氧化物涂层钛基电极强化寿命最长。循环伏安测试结果表明:3种酸刻蚀过后的Sn-Sb氧化物涂层电极的析氧电位基本相同,表明酸刻蚀对于该电极的析氧电位影响不大。     

阴极保护用钌-钛-铱-锰涂层钛阳极

研制了一种钌-钛-铱-锰氧化物涂层钛阳极,实验室研究和海上阴极保护实际试用表明,该电极在海水中有极化不大(100.0 A/m~2下不超过2V),耐高电流密度(8000A/m~2稳定工作超过三个月)消耗率低(3.1mg/A·Y)等优点。适合在海上阴极保护系统中试用。文中还讨论了钛-钌氧化物系电极钝化失效的原因,对改进这类电极性能的途径提出了看法。     

种植体用钛涂层不锈钢的研究

本研究采用低压等离子喷涂工艺，在317L不锈钢基体上喷涂了钛涂层，制备出钛涂层的种植体，通过动物的植入实验．研究了这种种植体的生物相容性；并综合利用扫描电镜、电子探针、X射线衍射仪等分斩仪器对涂层的微观结构、涂层-基体界面成分分布等进行了研究；同时也对涂层种植体的电化学性能进行了研究，结果表明，喷涂过程对不锈钢基体本身的力学性能影响很小；钛涂层结合良好，其与骨组织的生物相容性能优于未涂钛涂层的。     

集束电极电火花合成沉积TiN涂层组织及耐磨性能

为满足提高铜合金表面耐磨性能的需求，提出了一种利用集束钛电极在QAl9-4铝青铜旋转工件表面电火花合成沉积TiN涂层的新方法，并进行了试验研究。结果表明：在铜合金表面制备出了均匀连续的TiN涂层；涂层表面由细化了的晶粒结构构成，组织致密；电极丝对涂层表面有较强的磨削涂覆作用，显著降低了涂层表面粗糙度值；涂层主要由TiN硬质相构成，厚度为85 μm左右，显微硬度可达890 HV_0.05，约为基体（185 HV_0.05）的4.8倍；涂层与基体间具有合金化冶金结合的过渡层；涂层表面摩擦因数为0.125~0.2，远小于基体（0.23~0.35）且波动性较小，磨损率约为基体的49.6%，具有更好的减摩耐磨特性。     

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。