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1.
研究 AZ91D 镁合金在邻苯二甲酸氢钾-硼酸盐碱性环保型电解液中的阳极氧化行为。考察邻苯二甲酸氢钾对阳极氧化膜层性能的影响,并利用扫描电镜(SEM)、X 射线衍射(XRD)、动电位极化和电化学阻抗(EIS)进行分析表征。结果表明,邻苯二甲酸氢钾的浓度对阳极氧化成膜过程,氧化膜的表面形貌、厚度、相结构和耐腐蚀性能都有重要影响。在硼酸盐电解液中加入适量的邻苯二甲酸氢钾以后,制得的阳极氧化膜表面光滑、致密,与镁合金基体的结合力强,具有优异的耐腐蚀性能。  相似文献   

2.
镁合金环保型阳极氧化工艺研究   总被引:5,自引:0,他引:5  
通过环保型阳极氧化工艺在MB2镁合金表面获得了表面质量良好的银灰色氧化膜层,用金相显微硬度计、扫描电镜和X射线衍射等表面分析手段,研究了氧化膜层的显微硬度、截面形貌和相结构,并采用动电位扫描的电化学方法考察了氧化膜的耐腐蚀性能.结果表明:氧化膜层的主要成分为MgO、MgAl2O4、Al2O3;膜层具有多孔结构,孔径较为均匀,分为内外两层,外层为疏松层,内层为与基体结合牢固的致密层;阳极氧化电流密度和电解液中铝盐浓度是影响阳极氧化膜层性能的主要因素;所得膜层的显微硬度值高达558.4 HV,同时其耐蚀性能也远优于传统含铬DOW17工艺所成的防护膜,且所用电解液无铬无磷更为环保经济.  相似文献   

3.
An environmental-friendly electrolyte of silicate and borate, which contained an addition agent of 1H-benzotriazole (BTA) with low toxicity (LD50 of 965 mg/kg), was used to prepare an anodized film on AZ31B magnesium alloy under the constant current density of 1.5 A/dm2 at room temperature. Effects of BTA on the properties of the anodized film were studied by scanning electron microscopy (SEM), energy dispersion spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), loss weight measurement, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), respectively. The results demonstrated that anodized growth process, surface morphology, thickness, phase structure and corrosion resistance of the anodized film were strongly dependant on the BTA concentration, which might be attributed to the formation of an BTA adsorption layer on magnesium substrate surface. When the BTA concentration was 5 g/L in the electrolyte, a compact and thick anodized film could provide excellent corrosion resistance for AZ31B magnesium alloy.  相似文献   

4.
In order to improve titanium corrosion behavior, we can increase the thickness of oxide layer on titanium surface during anodizing process and by electrochemistry. In this research, self-color anodizing of Ti in sulfuric acid was done, and anodizing layers were created in different colors. The highest value of chromaticity was 37.8 for the anodized sample in 10 V, and the lowest value was 8.6 at 15 V. The oxide layer thickness was calculated by optical method (light refraction). The anodic film thickness increased by increasing the anodizing voltage. The highest thickness of anodic film was 190 nm in sulfuric acid solution for the anodized sample in 80 V. Corrosion resistance of anodized Ti was studied by potentiodynamic polarization curves in biological solution of Ringer’s at 37 °C. On increasing the anodizing voltage further, corrosion rate of the alloy increased from its lowest rate. The lowest rate of corrosion was for the sample anodized in 10 V, which was 0.96 × 10−3 mpy.  相似文献   

5.
通过试验,研究了合金成分、常温封孔、阳极氧化工艺条件对氧化膜耐蚀性,耐磨性的影响;讨论了这些因素对氧化膜耐蚀性、耐磨性的影响机理,指出了为保证氧化膜的耐蚀性、耐磨性而采取的工艺措施。  相似文献   

6.
用电化学极化和扫描电镜(SEM)观察法,研究了电流密 度、氧化时间和氧化温度等工艺参数对LC4铝合金阳极氧化膜的厚度、显微形貌和在NaCl溶 液中耐蚀性的影响,讨论了影响氧化膜耐蚀性的机制,提出了提高耐蚀性的最佳阳极氧化工 艺参数.  相似文献   

7.
目的提高铝锂合金胶接接头的强度与耐腐蚀性能。方法对铝锂合金板采用砂纸打磨、喷砂和磷酸阳极化处理,在表面处理后的基板上铺一层FM94胶,并加压固化,得到单搭接接头。分析不同表面处理后铝锂合金试样的表面形貌、表面粗糙度、表面自由能和表面化学组成,对接头进行湿热环境老化实验,测试湿热老化前后胶接接头的强度,研究揭示不同表面处理方法对胶接接头强度与抗湿热老化能力的影响。结果与砂纸打磨后的试样相比,喷砂与磷酸阳极化处理能显著提高铝锂合金试样的表面粗糙度和表面自由能。同时,经EDS分析发现,阳极化后铝锂合金表面氧元素大量增加。阳极化和喷砂处理后的接头强度分别为37.0、26.8MPa,而简单打磨过后的接头仅为16.4MPa。湿热老化后,磷酸阳极化处理的接头强度仅下降12.2%,而喷砂处理和砂纸打磨处理的接头强度分别下降了30.6%和19.5%。结论磷酸阳极化和喷砂处理均能增大铝锂合金胶接接头的强度,但阳极化处理效果更好,阳极化处理能显著加强接头的耐腐蚀能力,而喷砂处理则对接头的耐腐蚀能力无明显提升。  相似文献   

8.
适合于压铸镁合金着色的阳极氧化工艺研究   总被引:2,自引:0,他引:2  
利用正交试验,开发出一种新型环保型的适合着色的镁合金阳极氧化工艺,采用此工艺能在镁合金表面上形成灰白色、均匀、多孔的光滑膜层.这种膜层具有良好的着色效果,可获得多种颜色。利用电流-时间曲线、XRD、SEM对阳极氧化成膜过程、膜层成分、形貌和结构进行了研究。  相似文献   

9.
In this research, color anodizing of Ti-6Al-4V alloy was performed in phosphoric acid solution of 0.4 M concentration and within 30 s in different voltages (10-120 V) of a DC power supply. The effect of anodizing voltages on the color and thickness of anodized layers on Ti-6Al-4V alloy surface was surveyed. Thickness and refractive index of layers were measured by spectrophotometery and reflectance curves. According to the results, thickness of layers increased with increasing anodizing voltage and was in the range of 38-167 nm. Also the refractive index of anodic film was approximately constant at about 2 and increased inconsiderably with increasing anodizing voltage. Corrosion resistance of the anodized samples in 20 and 50 V was surveyed in physiological solutions of Ringer’s solution, Artificial Saliva solution, and Ringer’s + 150 mM H2O2 solution at the temperature of 37 °C by potentiodynamic polarization method. The anodized sample in 50 V indicated lower corrosion rate than the non-anodized sample as well as the sample which was anodized in 20 V in all solutions. The non-anodized sample indicated the highest corrosion rate of about 0.25 μA cm−2.  相似文献   

10.
2024铝合金混合酸阳极氧化   总被引:2,自引:2,他引:0  
目的在混合酸溶液中,对2024铝合金进行不同条件下的阳极氧化,并制备氧化膜,研究比较氧化膜厚度、表面形貌和耐腐蚀性等的不同。方法 2024铝合金在硫酸-磺基水杨酸-乳酸体系中进行阳极氧化,改变氧化时间(20~60 min)与氧化电流密度(2.5~4.5 A/dm^2),观察氧化膜的表面形貌、显微硬度、厚度、晶体结构以及耐蚀性的变化。结果每次实验的氧化时间为40 min不变,改变电流密度得到一系列阳极氧化膜,当电流密度为3.0 A/dm^2,自腐蚀电位最正,接近0.0 V时膜层的耐蚀性最好。若继续增加电流密度,则自腐蚀电位会负向移动。当电流密度为4.5 A/dm^2时,自腐蚀电位最负,为-1.1 V。保持电流密度为2.5 A/cm^2不变,改变氧化时间,得到一系列阳极氧化膜,当氧化时间达到50 min时,氧化膜的耐腐蚀性最好,自腐蚀电位为-0.6 V。XRD分析表明,氧化膜由γ-Al2O3和α-Al2O3组成。氧化膜的显微硬度和厚度会随着电流密度及时间的增加而增大,氧化膜硬度、厚度最大分别为372.3HV、6.8μm。结论当阳极氧化电流密度为3.0 A/d、氧化时间为50 min时,膜层的耐蚀性最好。  相似文献   

11.
The anodization of AZ91 magnesium alloy in an alkaline electrolyte of 100g/L NaOH 20g/L Na2B4O7·10H2O 50g/L C6H5Na3O7·2H2O 60g/L Na2SiO3·9H2O was studied.The corrosion resistance of the anodized films was studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques.The microstructure of the films was examined with scanning electronic microscope (SEM) and X-ray diffractometer (XRD).The results show that,under the experimental conditions,the optimum anodizing time and the optimum anodizing current density are 40min and 20mA/cm2 respectively for obtaining the anodic film with high corrosion resistance.The XRD pattern shows that the components of the anodized film consist of MgO and Mg2 (SiO4).  相似文献   

12.
为提高镁合金的耐腐蚀性能,采用无机熔盐电镀技术在镁合金表面电镀铝锰合金,其后在草酸溶液中对铝锰合金镀层进行阳极氧化处理,以制备耐蚀性优良的阳极氧化膜。采用扫描电镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)等对阳极氧化膜的微结构进行表征,采用电化学测试方法对阳极氧化膜的耐腐蚀性能进行评价。结果表明,Al-Mn合金镀层在草酸溶液中形成的阳极氧化膜主要由稳态的α-Al2O3和亚稳态的γ-Al2O3所组成,并含有少量的MnO2及Al(MnO4)3,该阳极氧化膜具有很强的绝缘特性,其腐蚀电流密度较Al-Mn合金镀层下降了约3个数量级,较基体镁合金下降了约6个数量级,极大地提高了镁合金的耐腐蚀性。  相似文献   

13.
目的通过含有硬脂酸添加剂的阳极氧化工艺,获得耐蚀性优异的镁合金阳极氧化膜。方法采用直流电源阳极氧化法,在含有2 g/L硬脂酸的碱性氧化液中进行阳极氧化。通过SEM、ImageJ软件和TT230测厚仪分析氧化膜的微观形貌和膜厚,通过FTIR、XPS和XRD分析膜层成分,通过电化学测试检测膜层的耐蚀性能。结果氧化液中添加硬脂酸后,制备的氧化膜层孔隙率降低,孔径减小,孔洞数量下降,厚度增大,致密度提高。膜层的自腐蚀电流密度为3.15×10^–7 A/cm^2,与未加硬脂酸制备的氧化膜相比,降低了2个数量级,耐蚀性显著提升。结论硬脂酸添加剂通过提升成膜电压,增强火花放电效应、表面活性剂作用,改变膜层成分等机制,提升膜层耐蚀性能。  相似文献   

14.
Physical vapor deposition method was utilized to apply Al coating onto Cu–10Al–13Mn alloy, then coated layer was anodized in different temperatures: 5 and 10°C as well as several potentials: 20, 30, 40, 50 V in order to achieve best anodizing parameters. The effects of anodizing parameters on alumina nanotube formation and corrosion resistance were investigated. Phase analysis on surface was conducted by X-ray diffraction method and nanotube characteristics was studied by scanning electron microscopy (SEM) and surface topology was investigated by atomic force microscopy (AFM). Additionally, the corrosion resistance of coatings was studied by potentiodynamic test in 1M NaCl solution. The results depicted that whole deposited Al layer was anodized and FCC alumina was formed merely. Polarization test results was illustrated that Al anodized layer significantly improved Cu–10Al–13Mn corrosion resistance. Uncoated specimen had highest corrosion rate and anodized layer in lower temperature and voltage had minimum alumina nanotube dimension; as a result, it had best corrosion behavior in NaCl corrosive solution.  相似文献   

15.
采用L9(34)正交试验,研究了一种无铬、无氟、无磷的适合着色的镁合金环保型阳极氧化工艺,测定了阳极氧化过程中槽电压随时间的变化曲线,并采用SEM和XRD分析了氧化膜的表面形貌、结构和成分.结果表明:阳极氧化膜主要由MgO、Mg2AlO4、MgSiO3和Al2O3组成,膜层为白色,光滑均匀,为不规则多孔结构,其孔径约1~3μm.这种多孔膜具有良好的着色效果,并且能对涂层起很好的锚着作用,提高了涂层与基底的结合力.  相似文献   

16.
目的 研究相同工艺参数下一次阳极氧化和二次阳极氧化对6061铝合金上氧化膜结构的影响,探究基体结构差异性与膜层生长行为及性能间的对应关系。方法 以商业6061铝合金和SPS粉末烧结铝合金为研究对象,针对不同基体在一次阳极氧化和二次阳极氧化过程中,围绕基体组织特征对膜层结构的影响展开系统研究。同时,对不同工艺方法制备出的不同结构特点的氧化膜进行封闭后处理,结合电化学测试方法对膜层的耐蚀性能进行分析对比。结果 相比一次氧化过程,商业6061铝合金和SPS铝合金的二次氧化电流密度分别由12.07、56.62 mA/cm2增加至13.68、64.8 mA/cm2,膜层生长速率增大。同时,一次氧化后在基体表面形成的有序凹坑结构有助于二次氧化中膜层多孔结构有序性的提升,其中SPS烧结铝合金膜层孔洞呈规则的“六边形”结构。二次阳极氧化过程可以有效减少基体表面阴极性金属间化合物颗粒的分布,提高氧化膜的连续性,增强相应膜层的耐蚀性。结论 二次阳极氧化可以使生成的氧化膜层更加均匀规整,且整体耐蚀性显著提高。  相似文献   

17.
Precipitation control of calcium phosphate on pure magnesium by anodization   总被引:1,自引:0,他引:1  
Calcium phosphate precipitated on pure magnesium from artificial plasma (modified Hanks’ solution) was varied by anodization and autoclaving, aiming the control of corrosion rate of bioabsorbable magnesium. Rough and smooth anodized film was formed depending on anodizing voltage in 1 N NaOH. The amount of calcium phosphate precipitated on the porous film was 2-3 times larger than that on the smooth film. The Ca/P ratio on the porous film was slightly higher than that on the smooth film. The autoclaving did not significantly influence the morphology of anodized film; however, the precipitation of calcium phosphate was restricted. No significant local corrosion occurred after the immersion in modified Hanks’ solution. It is demonstrated that the precipitation of calcium phosphate on magnesium can be controlled by anodization and autoclaving.  相似文献   

18.
目的研究一种绿色环保的表面处理方法,以提高镁合金的耐蚀性。方法采用化学浸泡法,以硝酸钇为成膜物质,在AZ31B镁合金表面成功制备一种新型稀土盐转化膜,并以氧化石墨烯为阻隔剂对该转化膜进行复合掺杂。采用扫描电镜(SEM)对膜层的表面形貌进行观察,采用析氢实验和电化学测试对不同试样在3.5%Na Cl溶液中的耐蚀性进行了研究。结果镁合金钇盐转化膜表面平整均一,覆盖良好。氧化石墨烯掺杂后的钇盐膜层表面出现了大小不均一的瘤状物质,膜层完整,未出现裂痕。析氢实验结果显示,经过处理的转化膜试样可以极大地抑制腐蚀反应的发生。由极化曲线可知,钇盐转化膜的存在使镁合金的腐蚀电位发生了明显正移,正移了150 m V;而氧化石墨烯掺杂的钇盐膜层的腐蚀电位相对于掺杂前变化不大,但其腐蚀电流密度是掺杂前的1/28。电化学交流阻抗谱的测试结果显示,氧化石墨烯掺杂钇盐转化膜的电荷转移电阻最大,Rct为2485?·cm2;钇盐转化膜的电荷转移电阻次之,Rct为1224?·cm2。两者的电荷转移电阻相对于未经处理的镁合金都有明显提升。结论钇盐转化膜可以明显提高AZ31B镁合金的耐蚀性,氧化石墨烯的加入可以进一步提高转化膜层的耐蚀性。  相似文献   

19.
2024-T3铝合金在硫酸-硼酸-磷酸中的阳极氧化和腐蚀行为   总被引:4,自引:0,他引:4  
在含有10%硫酸、5%硼酸和2%磷酸的混合电解液中,对2024-T3铝合金进行阳极氧化处理,以提高其耐腐蚀性能。使用电化学阻抗频谱分析研究阳极氧化处理后合金的腐蚀行为。利用塔菲尔图和盐水喷雾技术进行对比发现,与只用磷酸或硫酸和硼酸的电解液相比,使用含有10%硫酸、5%硼酸和2%磷酸的混合电解液阳极氧化处理后的2024-T3铝合金,具有更好的耐腐蚀性和持久性。该电解液可以替代普遍用于阳极氧化铝合金的铬酸盐浴。  相似文献   

20.
The newly developed high strength aluminum alloy Al-6wt.%Zn- 1wt.%Mg was anodized in acids by direct current to produce a protective anodic coating against abrasion and corrosion. Mechanical properties of the anodized finish, including microhardness, abrasion resistance and fatigue strength were evaluated in terms of the composition and temperature of the electrolyte, applied voltage, current density, duration of anodizing and sealing temperature. Pitting is destructive of the anodized finish particularly in a marine environment and thus can also serve as a direct measure of the efficacy of sealing procedures.The optimum conditions for anodizing Al-6wt.%Zn-1wt.%Mg are a bath of 5 wt.% oxalic acid with 3 wt.% formic acid as an additive, a current density of 4 A dm-2 for 30 min at 20 °C and sealing in boiling deionized water for 30 min. Results show that this anodized finish possesses good mechanical properties and corrosion resistance.  相似文献   

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