双相不锈钢焊接接头宏观金相试样的制备

采用标准推荐的不锈钢焊接接头宏观金相试样制备方法,发现双相不锈钢焊接接头的宏观金相形貌不清晰。将电解腐蚀方法应用至双相不锈钢焊接接头宏观金相试样的制备,通过试验确定了合适的电解液和电解腐蚀参数。结果表明:在电解液为10mL HNO_3溶液+90mL H_2O+1g NaCl,电流密度为1.11mA·mm~(-2),腐蚀时间为2min的条件下,可获得各区域清晰可见的双相不锈钢焊接接头宏观金相试样。     

电解抛光在6063铝合金金相试样制备中的应用

对6063铝合金的电解抛光方法进行了研究,根据电解抛光的一般原理通过试验选定了电解抛光的温度、时间、电流和电压等参数,制备出了晶界清晰、抛光面无划痕、符合显微组织观察和分析要求的金相试样,获得了比机械抛光效果更好的6063铝合金金相制样方法。     

铟电解精炼提纯方法的研究

研究了铟电解精炼提纯的方法及工艺。为了提高铟电解提纯的效果,建议使用电解液循环通过高纯铟柱的总体电解工艺流程。通过研究电解液组成及酸度、电流密度等关键参数对电解提纯的影响,得出铟电解精炼提纯的关键参数为:硫酸体系电解液,成分为100g/L硫酸铟+70～100g/L氯化钠+0.5g/L明胶;电解液的酸度控制在pH=2～2.5;设计电解槽的同极距为40～50mm;阴极板用钛板;控制电解过程中的电流密度在35～65A/m2之间;电解过程中,电解液循环通过高纯铟柱,达到电解过程中净化铟电解液的效果,显著提高铟电解精炼提纯的效果。     

变形镁合金EBSD试样的制备

综述了国内外的变形镁合金电子背散射衍射(EBSD)试样的制备方法和步骤,阐述了制样过程中的切割、镶嵌、研磨和最终抛光各步骤的相互影响及对EBSD数据采集及分析的影响。总结了电解抛光技术在变形镁合金EBSD试样制备中的应用,最后展望了镁合金EBSD试样制备方法的发展方向。     

影响不锈钢草酸侵蚀试验的有关因素

对不锈钢10％草酸电解试验的各参数进行了对比试验研究，试验结果表明，侵蚀电流和电解时间是影响实验结果的主要因素，电解液中草酸质量分数在12％－5％内变化时对试验结果无影响。     

金相分析中恒电位深腐蚀法的应用

一、前言 在普通金相试样制备中,应用电化学原理,即利用不同相组织电化学性能的差异,在一定的电解液系统中通过选择腐蚀来鉴别不同的相组织。但由于不同金属相的极化作用,很难得到良好的效果。而深腐蚀法可以克服这些弊端,运用恒电位仪为主的制样设备,可以制备出反差最佳的金相试样。     

低合金钢焊接接头低倍检验金相试样的制备

某出口低合金钢转向架焊接构架的焊接工艺评定对该焊接接头的低倍检验有较高的要求。通过合理配制腐蚀溶液,增加腐蚀溶液的种类,并严格规范腐蚀步骤,确定了合理的低倍检验用金相试样的制备工艺。结果表明:使用8%硝酸酒精溶液(体积分数)及过硫酸铵饱和水溶液制备的焊接接头金相试样各区域清晰可见,制样质量稳定,能够满足该焊接构架的焊接工艺评定要求。     

互换电极电解法快速制备高 Al13含量的聚合氯化铝

以AlCl3为原料，采用互换电极电解法制备高Al13含量的聚合氯化铝．本工作对电解过程中Al13的形成机理进行了探讨，并研究了电解电压、Al^3＋的初始浓度、电解液的循环搅拌速度和阴阳电极的互换频率对Al13的合成速度、Al13占总铝的比率及电解所需时间的影响，得出了电解法制备Al13的最佳工艺条件：电极互换频率为1次．min、电解液中Al^3＋的初始浓度为0．5000mol·L^-1、电解电压为12V和0．5L．min^-1的电解液循环搅拌速度，在此条件下电解125min可制得碱化度为82．0％，A113占总铝的比率达91．2％的液体产品．     

激光选区熔化TC4钛合金高氯酸电解抛光工艺研究

以高氯酸溶液为电解液,对激光选区熔化TC4钛合金试样进行电解抛光工艺试验,研究了电流密度、时间、温度、阴极材料等相关参数对试样的粗糙度、失重率、减薄率的影响,同时,对抛光处理后试样的表面形貌进行了分析。研究结果表明,按高氯酸10m L、冰乙酸100m L、水12m L配比的混合电解液,在电流密度为(0.27~0.37)A·cm^-2,温度(30~35)℃,时间(15~20)min的条件下进行电解抛光所得的效果较好。试样表面粗糙度Ra由13.66μm降至1.52μm,厚度减薄率在(6~7)%左右,试样表面平整光亮,均一性较好。     

低碳IF钢薄板纯铁素体组织显示方法

采用浸蚀法和电解抛光法对IF钢(DC06钢和CR5钢)进行制样,对比了2种方法的制样效果,并分析了浸蚀剂种类及浸蚀时间对制样效果的影响.结果表明:浸蚀法制样较电解抛光法简单,但浸蚀法需要通过多次试验才能确定最佳浸蚀时间;电解抛光法的制样过程复杂,但制样效果较好,可获得晶界清晰的试样;使用体积分数为4％的硝酸酒精溶液浸蚀...     

Electrolytic preparation of chemically resistant alloys for radionuclide immobilization

An electrolytic method for preparing chemically resistant Pm-Ni alloys was developed. Optimal electrolysis conditions ensuring maximal Pm recovery from the electrolyte (up to 95%) with the alloy formation were determined. Side steps of the process were examined. The main of them is reduction of Pm in the bulk of the electrolyte with alkali metal subions.     

Electrolytic Method for Preparing Chemically Resistant Alloys for Americium Immobilization

An electrolytic method for preparing chemically resistant Am–Ni alloys was studied. Optimum electrolysis conditions ensuring the maximal (up to 95%) recovery of Am from the electrolyte with the alloy formation were found. The compositions of the alloys formed in the process were determined.     

Tunable optical properties of colloidal quantum dots in electrolytic environments

The absorption spectra of colloidal cadmium sulfide quantum dots in electrolytic solutions are found to manifest a shift in the absorption threshold as the concentration of the electrolyte is varied. These results are consistent with a shift in the absorption threshold that would be caused by electrolytic screening of the field caused by the intrinsic spontaneous polarisation of these würtzite structured quantum dots. These electrolyte-dependent absorption properties provide a potential means of gaining insights on the variable extracellular and intracellular electrolytic concentrations that are present in biological systems.     

Molecular Design of the Solid Copolymer Electrolyte- Poly(styrene-b-ethylene oxide) for Lithium Ion Batteries

Poly(ethylene oxide) (PEO) is a commonly used electrolytic polymer in lithium ion batteries because of its high viscosity which allows fabricating thin layers. However, its inherent low ionic conductivity must be enhanced by the addition of highly conductive salt additives. Also its weak mechanical strength needs a complementary block, such as poly(styrene) (PS), to strengthen the electrolytic membrane during charging/discharging processes. PS is a strong material to complement the PEO and to create a reinforced copolymer electrolyte termed as the poly(styrene-b-ethylene oxide) (PS-PEO). In this work, molecular dynamics simulations are employed to study the effects of doping the PS constituents into the PEO based copolymer electrolyte. The results reveal that strengthening the mechanical strength increases the intra conjugation forces which penalize the ionic conductivity. Hence both ionic conductivity and mechanical strength of the copolymer have to be compromised. This paper designs the optimized molecular structure through the atomistic analysis instead of try-and-error experiments.     

射流电铸快速成形纳米晶铜的研究

采用射流电铸快速成形新技术研究了制备块体纳米晶铜的工艺，制备了具有一定形状的块体纳米晶铜样品，用X射线衍射法分析了纳米晶铜的微观组织结构，结果表明，电铸电流密度和电铸速度随电铸电压和喷射速度的增大而提高，该新技术方法可用于快速制备具有一定形状的块体纳米晶铜材料。     

Systematic Study of Nanocrystalline Plasma Electrolytic Nitrocarburising of 316L Austenitic Stainless Steel for Corrosion Protection

A number of studies have been reported on the use of nanocrystalline plasma electrolytic nitrocarburising technology for surface hardening of stainless steels for higher corrosion resistance resulted from this technique. However, very few studies have focused on the optimization of the nanocrystalline plasma electrolytic nitrocarburising process parameters. In this study, a design of experiment （DOE） technique, the Taguchi method, has been used to optimize the nanocrystalline plasma electrolytic nitrocarburising not only for surface hardening but also for the corrosion protection of 316L austenitic stainless steel by controlling the coating processes factors. The experimental design consisted of four factors （Urea concentration, electrical conductivity of electrolyte, voltage and duration of process）, each containing three levels. Potentiodynamic polarization measurements were carried out to determine the corrosion resistance of the coated samples. The results were analyzed with related software. An analysis of the mean of signal-to-noise （S/N） ratio indicated that the corrosion resistance of nanocrystalline plasma electrolytic nitrocarburised 316L stainless steel was influenced significantly by the levels in the Taguchi orthogonal array. The optimized coating parameters for corrosion resistance are 1150 g/L for urea concentration, 360 mS/cm for electrical conductivity of electrolyte, 260 V for applied voltage, 6 min for treatment time. The percentage of contribution for each factor was determined by the analysis of variance （ANOVA）. The results showed that the applied voltage is the most significant factor affecting the corrosion resistance of the coatings.     

Ta-Ta2O5-电解液导电体系界面特性的实验研究

分析了阀金属钽氧化膜的形成过程,伏安特性测试结果表明Ta-Ta2O5-电解液体系具有单向导电性.电场作用下,电解液中O2-跃过氧化膜/电解液界面,在氧化膜中形成定向迁移,同时引发膜内二次电子场助发射是该体系的主要导电机理.实验表明,大量二次电子导致介质膜雪崩式击穿是该体系闪火的主要原因,在电解液中添加适量有机物,可以屏蔽O2-使电解液的闪火电压提高30V以上,从而提高液体钽电解电容器的性能.     

钛基二氧化铅作为阳极电解制备羟基氧化镍的研究

使用钛基二氧化铅作为阳极,不锈钢作为阴极进行了电解制备羟基氧化镍(NiOOH)的研究,并和以泡沫镍为阴阳极的体系在氧化机理,氧化效率,产品型貌等方面进行了比较,结果说明钛基二氧化铅作为阳极电解法制备羟基氧化镍是一种更为高效、绿色的制备方法.     

Kinetics of the initial stage of electrolytic deposition of metals I. General theory

The process of the electrolytic deposition of metals is considered as a particular case of heterogeneous phase formation. The basic set of kinetic equations describing the initial stage of formation of a thin metal film on an inert cathode is formulated in a general form. With the aid of these equations the mean crystallite radius, the overvoltage and the electric current flowing through the system can be found as functions of time if the total “ohmic” resistance of the electrolytic cell is known. Taking into account the Gibbs-Thomson effect of crystallite curvature, expressions are derived for this resistance in the particular cases when the crystallite growth is limited solely (i) by the specific electrical conductivity of the electrolyte, (ii) by volume diffusion of the metal ions from the bulk of the electrolyte towards the surface of the growing crystallites, and (iii) by impediments accompanying the transition of the metal ions through the crystallite/electrolyte interphase boundary. Finally, it is shown that electrodeposition processes characterized by other types of crystallite growth control can also be analysed by means of the basic set of kinetic equations if the total cell resistance is properly defined.