硫酸-甲醇体系钨电解抛光的可行性研究

以硫酸-甲醇酸性体系作为电解液,对钨箔进行电解抛光研究.抛光后钨的表面均方根粗糙度和反射率的测试结果表明,该体系完全适用于金属钨的电化学抛光,对钨的阳极溶解行为进行了分析,讨论了溶液组成、槽电压、温度和搅拌速率对电抛光后钨表面粗糙度的影响.初步确定了金属钨电解抛光的工艺参数为:硫酸与甲醇的体积比1:7,槽电压15～22V,温度15～25℃,搅拌速率10m/s.     

硫酸-磷酸-铬酸电化学抛光对钼片表面状态的影响

以硫酸-磷酸-铬酸体系为电解液,对钼片进行电化学抛光。通过测定阴极极化曲线,研究了抛光过程中电压和电流之间的关系。表征了抛光前后钼片的微观形貌、粗糙度和尺寸等。在2.0 A/cm~2下对钼片电化学抛光30 s,可得到均匀平整、无明显坑点的表面,粗糙度由抛光前的0.20μm降至0.05μm。通过严格控制抛光时间可有效保证样品的几何尺寸精度。     

硫酸–甲醇体系钨电解抛光的可行性研究

以硫酸–甲醇酸性体系作为电解液,对钨箔进行电解抛光研究。抛光后钨的表面均方根粗糙度和反射率的测试结果表明,该体系完全适用于金属钨的电化学抛光。对钨的阳极溶解行为进行了分析,讨论了溶液组成、槽电压、温度和搅拌速率对电抛光后钨表面粗糙度的影响。初步确定了金属钨电解抛光的工艺参数为:硫酸与甲醇的体积比1∶7,槽电压15～22 V,温度15～25°C,搅拌速率10 m/s。     

电流密度和抛光时间对镍钛合金管电解抛光的影响

采用高氯酸?冰醋酸体系对镍钛合金管电解抛光.在温度25°C及抛光间隙15 mm的条件下研究了抛光时间(60～120 s)和电流密度(0.75～1.75 A/cm2)对抛光效果的影响.结果表明,随着抛光时间延长或电流密度增大,钛合金管的表面粗糙度先减小后增大,残余压应力先增大后减小,较佳的电流密度和抛光时间分别为1.15 A/cm2和90 s.在该条件下电解抛光后,镍钛合金管表面平整光亮,凹坑最少,表面粗糙度最小(为53.8 nm),表面残余压应力最大(为175.8 MPa).     

脉冲参数对TC4钛合金电化学抛光的影响

采用脉冲电源对TC4钛合金进行电化学抛光，研究了电压、脉冲频率和占空比对抛光效果的影响。结果表明，TC4钛合金的表面粗糙度和材料去除率随着脉冲频率增大而呈先减小后增大的变化趋势；随着电压或占空比增大，TC4钛合金的表面粗糙度先减小后增大，材料去除率增大。在温度20℃、极间距4 cm、电压25 V、脉冲频率1 000 Hz及占空比40%的条件下电化学抛光6 min后，TC4钛合金的材料去除率为23.85μm/min，表面粗糙度(Ra)从初始的6.21μm降到0.84μm，表面平整均匀。     

激光选区熔化316L不锈钢电解抛光工艺

采用绿色环保的氯化钠-乙二醇电解抛光液对激光选区熔化技术(SLM)制备的316L不锈钢样件进行电解抛光,以改善其表面品质。探究了抛光的电流密度、温度和时间对表面粗糙度及微观形貌的影响。结果表明：当电流密度为2.7 A/cm²,抛光时间为10 min,抛光温度为80°C时,可获得镜面效果,表面粗糙度(Ra)低至0.768μm。     

化学抛光对铝阳极氧化膜影响研究

利用表面粗糙度测量、金相显微镜和SEM对铝基体表面和膜的微观形貌观测,分别讨论了化学抛光时间、抛光液体积、使用次数和抛光温度对表面粗糙度和造孔表面形貌影响;结果表明,抛光时间、抛光液体积、使用次数和抛光温度对表面粗糙度和造孔表面形貌有不同程度的影响;最佳抛光时间2 min,最佳的制件面积：抛光液体积=2 cm2∶80 mL,使用前5次效果不变,最佳操作温度为100～105℃。     

电化学抛光对HR-1不锈钢表面的影响

以硫酸-磷酸混合液为电解液,考察了电化学抛光技术对HR-1不锈钢表面的影响。通过激光扫描共聚焦显微镜观察样品的表面形貌,并利用电子天平测量样品的质量变化。结果表明:当电流密度为80A/dm2,温度为90℃,抛光时间为60s时,样品表面的平整度最高,机械加工痕迹基本消失,无明显的尖峰与坑点,粗糙度小于0.18μm。为保证样品的尺寸精度,需要控制抛光时间。     

钛基氧化物涂层阳极的修复

采用熔盐法去除钛基氧化物阳极表面的失效涂层,通过X射线荧光光谱分析及粗糙度测量,考察了工艺条件对涂层去除效果的影响。通过循环伏安曲线、极化曲线、强化寿命测试分析了在去除失效涂层的钛基体上重涂修复所得到的钛阳极的电化学性能。结果表明,当KOH与KNO_3的质量比为5∶1、反应温度为450℃时,8 min可完全去除钛阳极表面的失效涂层,而又不会损伤钛基体及改变其表面粗糙度。修复后钛阳极的电化学性能与新制备的钛阳极相当,而成本仅为新制备钛阳极的57%,还可以回收贵金属。     

HNO3-H3PO4-HCl体系化学抛光不锈钢的研究

0 前言 不锈钢因其优异的耐蚀性和装饰性在工业生产及日常生活中得到了广泛应用,但不锈钢制品在加工过程中表面易生成一层黑色氧化皮,且该氧化皮有一定粗糙度.为改善不锈钢制品的耐蚀性、粗糙度和装饰性,须进行抛光处理[1].金属抛光处理通常分为机械抛光、电化学抛光和化学抛光.化学抛光设备简单、成本低、效率高、容易获得光亮如镜的表面、可以抛光形状复杂的制品而被广泛应用[2].     

激光选区熔化TC4钛合金在氨基磺酸−甲酰胺溶液中的电解抛光

以氨基磺酸?甲酰胺非水溶液作为电解液,对激光选区熔化钛合金TC4进行电解抛光。初步研究了电流密度和加工时间对不同构建角度的钛合金抛光后表面粗糙度和材料去除量的影响。在电流密度1 A/cm2和极间距14 mm的条件下抛光25 min时光整效果最佳,钛合金的耐蚀性得到增强,硬度无明显变化。     

电解抛光对镍钛合金生物兼容性的影响

采用高氯酸和冰醋酸体积比为1∶18的混合溶液,在电流密度1.05 A/cm²、抛光间距20 mm和温度15°C的条件下对镍钛合金管电解抛光90 s。对比了抛光前后镍钛合金管外表面的形貌、粗糙度(Ra)、亲水性、耐蚀性和生物相容性。结果表明,电解抛光后镍钛合金表面平整、光亮,Ra=51.1 nm,水接触角为44.2°,在Hank’s模拟体液中的耐蚀性和生物兼容性均有改善。     

Polishing effect on anodic titania nanotube formation

Titania nanotubes represent exciting opportunities in solar cell, sensing, and catalytic applications. In this work, four different surface polishing conditions: as-received, chemical polishing, mechanical polishing, and electropolishing, are studied in order to understand the effect of different surface conditions on the anodization process and nanotube morphology. At the same anodization condition of 100 V in 0.1 M NH₄F ethylene glycol at 0 °C for 3 min, the as-received and mechanically polished samples show nano-tubular surfaces while the chemically polished and electropolished samples have oxide layers on the top of the nanotubes. The nanotube morphologies, anodization current vs. time curves, and the bottom barrier layers are all related to the Ti surface conditions. The electropolished surface leads to the most homogeneous TiO₂ nanotube formation.     

Electropolishing of 304 stainless steel: Surface roughness control using experimental design strategies and a summarized electropolishing model

The electropolishing (EP) settings for obtaining 304 stainless steel (304SS) with variable surface roughness factors (Ra) in a mixture containing phosphoric acid, sulfuric acid, and glycerol were achieved using experimental design strategies, including the fractional factorial design (FFD) coupled with the response surface methodology (RSM) and the path of the steepest ascent. The bath temperature and polishing time were found to be the strongest factors affecting Ra of 304SS in the FFD study. The glycerol content and polishing current density involved strong interactions with the bath temperature although both factors only showed marginal significant effects. The effects of bath temperature and polishing time on Ra of 304SS were examined in the study of the steepest ascent path for controlling the surface roughness. The results showed that Ra of 304SS is decreased with decreasing the bath temperature and polishing time but increased when the temperature was lower than 20 °C. A summarized model with a new idea on the molecular interactions in the polishing bath is proposed to elucidate the phenomena found in this work. The morphologies and Ra of 304SS electropolished under various conditions were examined by means of the SEM photographs and AFM analyses.     

A super-high speed polishing technique for CVD diamond films

A new set-up for polishing of CVD diamond films on a high speed rotating titanium plate has been developed. The influence of polishing pressure on the surface character, roughness and material removal rate have been studied by using scanning electron microscopy, stylus profilometer, X-ray photoelectron spectroscopy and Raman spectroscopy before and after polishing, respectively. The results showed that the material removal mechanism is mainly the chemical reaction between carbon and titanium and the diffusion of carbon atoms into the polishing plate during the super-high speed polishing. The current method exhibits a high polishing rate in only a few hours. This preliminary result reveals a great potential for commercializing.     

Fabrication of Titanium Bipolar Plates by Rubber Forming Process and Evaluation Characteristics of TiN coated Titanium Bipolar Plates

In this study, the rubber forming process is used to fabricate a micro‐channel titanium plate for a PEM fuel cell. The micro‐channel plate is fabricated using a 200 ton hydraulic press, and various parameters (punch speed, press pressure, rubber thickness, rubber hardness) are investigated in order to evaluate the formability. TiN films are deposited by reactive DC magnetron sputtering (DCMS) with an electromagnetic field system (EMFS). For the uncoated titanium and TiN‐coated titanium substrates, the hardness, surface roughness, and corrosion resistance are estimated by nano‐indentation and electrochemical methods, respectively. The improved corrosion resistance of the TiN films can be attributed to the densification of the film caused by enhancement of nitrification with increasing high reactive nitrogen radicals. The uncoated titanium and TiN‐coated titanium bipolar plates are combined with a unit cell for a performance test, and respective current densities of 0.396 and 0.888 A cm⁻² at 0.6 V are obtained.     

38DD350型电解槽阳极钛板与钢板的腐蚀原因

通过对38DD350型电解槽的现场调查,总结了阳极钛板和钢板的腐蚀形态。应用电化学理论分析了钛板的点蚀原因和面腐蚀原因,指出由于钛板的塑性变形而形成的微观电池,以及电解电压的升高都是钛板出现点蚀的原因;供氧差异电池的存在也是钛板出现面腐蚀的原因。而钢板的腐蚀主要是由电偶腐蚀造成的。并给出相应的改进建议。     

电流密度对Ti 6Al 4V微弧氧化膜形貌和性能的影响

采用NaAlO2-Na3PO4-NaF溶液体系,研究了电流密度对Ti 6Al 4V合金微弧氧化膜厚度、生长速率、表面形貌、粗糙度、组成相以及氧化膜耐蚀性、耐磨性等影响.结果表明,(1)在试验的电流密度范围内,氧化膜的厚度随电流密度的增大呈线性增大,但氧化膜的粗糙度却几乎呈指数增大,表面质量变差;(2)在质量分数为3.5%的NaCl溶液中显示了比Ti 6Al 4V钛合金更好的耐蚀性;(3)在干摩擦条件下,氧化膜的摩擦系数高于基体的,氧化膜的磨损机制为脆性断裂.     

不锈钢电解刷式抛光工艺研究

阐述了不锈钢电解刷式抛光的原理和工艺过程。以不锈钢筒体为研究对象,采用不锈钢刷式抛光工艺进行试验研究。该工艺可降低工件表面粗糙度,使其表面光滑、耐腐蚀。     

光催化氧化对GaN材料腐蚀电化学及化学机械抛光的影响

考察了氮化镓(GaN)晶片在不同质量分数和pH的溴酸钾(KBrO3)溶液中的腐蚀电化学行为.结果显示,GaN在溴酸钾质量分数为1％时腐蚀电位最低.在此基础上使用光催化氧化法能够显著降低腐蚀电位,使GaN材料的腐蚀速率进一步提高.CMP实验结果显示:紫外光(UV)的加入使GaN在1％KBrO3溶液(pH=4)中的抛光速率...