镁合金微弧氧化陶瓷层的耐蚀性

通过NaCl中性盐雾腐蚀试验定性地分析镁合金微弧氧化陶瓷层的耐蚀性，初步研究了陶瓷层表面微观结构对其耐蚀性的影响。结果表明：镁合金微弧氧化陶瓷层的微观组织结构的结合方式和生长方式直接影响其耐蚀性，微弧氧化试样的耐蚀性与陶瓷的厚度有关，陶瓷层厚度的增加并不一定能使其耐蚀性提高。     

Corrosion resistance of ultrasonic soldered aluminium joint using Zn-based solder alloy

In order to obtain high strength aluminium butt joints with high corrosion resistance, ultrasonic soldering of 1070 and 5056 rods was conducted using quasi-melting Zn–18Sn (mass%) alloy and Zn–38A1 alloy. Ultrasonic vibrations were applied at soldering temperature ranging 533–723 K through aluminium rods without using of a solder bath. To evaluate the corrosion resistance of solder joints, tensile tests were conducted after immersion in a 5% NaCl aqueous solution. Though joint strength decreased with an increase in immersion time in the NaCl aqueous solution because of corrosion in the joints, corrosion resistance of 5056 joints with Zn–38A1 alloy was higher than that of joints with Zn–18Sn alloy irrespective of aluminium base material. The strength of joints with Zn–18Sn alloy rapidly decreased by immersion in the NaCl aqueous solution. In these joints, corrosion occurred locally in the soldered interface. Corrosion potential of these joints was unusually lower than that of the solder alloy. In contrast, corrosion occurred slowly in the solder layer in 5056 joints with Zn–38A1 alloy. Corrosion potential of the joints was equivalent to that of the solder alloy.     

Corrosion resistance,composition and structure of RE chemical conversion coating on magnesium alloy

Golden yellow rare earths chemical conversion coating was obtained on the surface of magnesium alloy by immersing in cerium sulfate solution.The corrosion resistance of RE conversion coating was evaluated using inmersion test and potentiodynamic polarization measurements in 3.5%NaCl solution.The morphologies of samples before corrosion and after corrosion were observed by SEM.The structures and compositions of the RE conversion coating were studied by means of XPS,XRD and IR.The results show that,the con...     

机械研磨对电沉积Ni镀层微观结构与性能的影响(英文)

在电沉积Ni过程中,向镀液中加入介质小球,介质小球以不同频率冲击镀件表面对镀层形成机械研磨。用SEM观察镀层表面、截面形貌,用TEM、XRD研究镀层的微观结构与结晶状态,测试镀层的极化曲线(PC)与交流阻抗频谱(EIS)等电化学性能。测试镀层的显微硬度与抗拉强度等力学性能。结果表明:在电沉积Ni过程中,对镀层实施机械研磨使镀层表面变得光滑,镀层孔隙率降低,致密度增加,镀层厚度减小,机械研磨促进镀层表面与内部晶粒尺寸的明显细化及镀层内部的压应力形成,从而导致镀层的耐蚀能力显著增强,抗拉强度与硬度显著提高。     

Mg-4.0Zn-2.0Sr-0.4Ca合金复合涂层的耐腐蚀性能

通过环保型阳极氧化工艺及聚合沉积技术在生物材料Mg-4.0Zn-2.0Sr-0.4Ca合金表面逐层制备阳极氧化膜、SiO₂溶胶凝胶、聚多巴胺(PDA)和壳聚糖(CS)复合涂层。采用扫描电镜(SEM)、X射线衍射仪(XRD)观察涂层形貌并确定相组成,采用电化学测试、SBF浸泡试验比较涂层对合金耐蚀性能的影响。结果表明,制备的复合涂层致密完整无缺陷。在SBF溶液中,复合涂层随腐蚀时间的延长逐渐产生裂纹并破碎,产生较小的腐蚀坑,腐蚀在一定程度上被控制在表面,而无涂层Mg-4.0Zn-2.0Sr-0.4Ca合金在SBF溶液中的腐蚀以点蚀和局部腐蚀为主,且腐蚀程度随腐蚀时间的延长而加剧。复合涂层在SBF溶液中的腐蚀电流密度、腐蚀电位和平均腐蚀速率分别为5.7039 μA/cm²、-1.4203 V(vs SCE)和0.163 g/(m²·h),均优于无涂层镁合金,且平均腐蚀速率降幅达50%以上,说明制备的复合涂层可显著提高Mg-4.0Zn-2.0Sr-0.4Ca合金的耐腐蚀性能。     

铁基非晶态合金涂层表面耐磨损及耐腐蚀性能研究

铁基非晶态合金凭借优异的耐磨和耐腐蚀性能在石油、煤电、钢铁和船舶等领域得到广泛应用。本文利用超音速火焰喷涂工艺在316不锈钢基体上制备铁基非晶态合金涂层,研究了涂层的磨削性能、涂层磨削表面的耐磨性能和耐腐蚀性能。研究结果表明三个磨削参数中,磨削深度对涂层表面的表面粗糙度及耐腐蚀性能影响最大,进给速度次之;而进给速度对涂层表面耐磨性能影响最大,磨削深度次之;磨削速度对涂层表面的表面粗糙度、耐磨性能和耐腐蚀性能影响较小。最后,根据不同的涂层性能要求对磨削参数组合进行优化。     

RE-Fe基合金热喷涂层的耐腐蚀性能

通过热喷涂的方法制备了添加稀土组分和适量铜组元的RE-Fe基合金涂层。采用液态浸渍法、电化学测试、盐雾实验以及涂层表面腐蚀形貌SEM观察等方法对不同成分、不同喷后处理工艺的RE-Fe基合金涂层的耐腐蚀性能进行研究。结果表明:添加适量的稀土组分和铜组元,使Fe基合金涂层的自腐蚀电位正移,维钝电流密度和致钝电流密度下降,明显地提高了Fe基合金(Fe-Cr-Ni-B-Si)涂层在酸类腐蚀介质中的耐腐蚀性能;同时也有效地提高了涂层抗盐雾气氛腐蚀的能力;其中以添加2%RE氧化物(质量分数)涂层(封孔后)的综合效果最佳。     

Electrochemical behavior of electroplated Zn-P alloy

1　ＩＮＴＲＯＤＵＣＴＩＯＮＥｌｅｃｔｒｏｐｌａｔｅｄＺｎ Ｐｃｏａｔｉｎｇｓｅｘｈｉｂｉｔａｒａｎｇｅｏｆｆａｓｃｉｎａｔｉｎｇｐｒｏｐｅｒｔｉｅｓ ,ｓｕｃｈａｓｈｉｇｈｃｏｒｒｏｓｉｏｎｒｅｓｉｓ ｔａｎｃｅ ,ｅｘｃｅｌｌｅｎｔ ｐａｉｎｔａｂｉｌｉｔｙａｎｄ ｐｈｏｓｐｈｏｒａｔａｂｉｌｉｔｙ ,ｆｉｎｅｗｅｌｄａｂｉｌｉｔｙａｎｄｆｏｒｍａｂｉｌｉｔｙ[1] .Ｔｈｅｒｅｆｏｒｅ ,ｉｎｒｅ ｃｅｎｔｙｅａｒｓ ,ｔｈｅｒｅｈａｖｅｂｅｅｎｓｅｖｅｒａｌｉｎｖｅｓｔｉｇａｔｉｏｎｓｏｎｐｒｅｐａｒｉｎｇ…     

稳恒磁场下Ni-W合金镀膜的制备与耐蚀性

研究了施加稳恒磁场(0~1 T)对电镀Ni-W合金的影响。测定不同方向、不同强度稳恒磁场下的电流效率、合金组成及镀层的耐蚀性,并用扫描电镜和X射线衍射对镀层的微观形貌及结构进行了观察和分析。对实验结果进行了分析讨论,找出稳恒磁场对这些性能指标的影响规律。结果表明:与不施加磁场相比,施加磁场后镀层的表面更均匀、细致、平整;镀层的含钨量上升:当B⊥J,B=1.0 T时,含钨量上升了约7%;当B∥J,B=1.0 T时,含钨量上升了约9%;镀膜的非晶化程度增强;镀膜的耐蚀性提高;但Ni-W合金电镀的电流效率降低。     

Wear resistance and hot corrosion behaviour of laser cladding Co-based alloy

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｒｉｎｇｔｈｅｏｐｅｒａｔｉｏｎｏｆｇａｓｔｕｒｂｉｎｅｓ ,ｔｈｅｔｅｍ ｐｅｒａｔｕｒｅｉｎｓｉｄｅｔｈｅｔｕｒｂｉｎｅｃａｎｒｅａｃｈ 90 0～ 10 0 0℃ｏｒａｂｏｖｅ.Ｕｓｕａｌｌｙｔｈｅｃｏｍｐｏｎｅｎｔｓｉｎｔｈｅｈｏｔ ｇａｓ ｐａｔｈｗｉｌｌｓｕｆｆｅｒｃａｔａｓｔｒｏｐｈｉｃｓｕｒｆａｃｅａｔｔａｃｋｋｎｏｗｎａｓｈｏｔｃｏｒｒｏｓｉｏｎｏｒｓｕｌｐｈｉｄａｔｉｏｎ .Ｓｏｔｈｅａｌｌｏｙｓｕｓｅｄａｓｔｈｅｔｕｒｂｉｎｅｃｏｍｐｏｎｅｎｔｎｅｅｄｔｏｂｅｈ…     

Corrosion resistance properties of AZ31 magnesium alloy after Ti ion implantation

Magnesium alloys have a wide range of applications in industry; however, their corrosion resistance, wear resistance, and hardness are rather poor, which limit their applications. Ti ion was implanted into the AZ31 magnesium alloy surface by metal vapor vacuum arc (MEVVA) implanter. This metal arc ion source has a broad beam and high current capabilities. The implantation energy was fixed at 45 keV and the dose was at 9 × 1017 cm?2. Through ion implantation, Ti ion implantation layer with approximately 900 nm in thickness was directly formed on the surface of AZ31 magnesium alloy, by which its surface property greatly improved. The chemical states of some typical elements of the ion implantation layer were analyzed by means of X-ray photoelectron spectroscopy (XPS), while the cross sectional morphology of the ion im-plantation layer and the phase structure were observed by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The property of corrosion resistance of the Ti ion implanted layer was studied by the CS300P electrochemistry corrosion workstation in 3.5% NaCl solution. The results showed that the property of corrosion resistance was enhanced remarkably, while the corrosion velocity was obviously slowed down.     

镁合金微弧氧化陶瓷膜的制备及耐蚀性能

利用微弧氧化技术在AZ91D镁合金表面原位生成含有钙、磷元素的陶瓷膜层.用SEM、XRD、EDS等研究陶瓷膜微观形貌、相组成及元素含量,利用Tafel和EIS技术来评价陶瓷膜的腐蚀性能.结果表明,所制备的陶瓷膜层成功地引入了钙和磷元素,陶瓷膜层主要由Mg2SiO4和MgO相组成.增加钙盐浓度,可以使膜层内的钙元素含量增多,微孔增加并且出现了微裂纹.电化学测试表明陶瓷膜使得镁合金在0.9%NaCl生理盐水中的耐蚀性提高了1～2个数量级,当钙盐浓度为0.3 g/L时,陶瓷膜层的耐蚀性最好.     

Mn添加量对Mg-2Zn合金组织及生物耐蚀性的影响

研究了Mn添加量对Mg-2Zn合金显微组织和耐腐蚀性能的影响。结果表明,3种不同Mn含量的Mg-2Zn合金显微组织差别不明显,但当Mn的加入量超过0.5%时,显微组织中析出的Mn含量增多;电化学与浸泡试验结果表明Mg-2Zn-0.2Mn与Mg-2Zn-0.5Mn合金的耐蚀性相近,但Mg-2Zn-1.0Mn合金的耐蚀性明显下降。     

镁合金表面电弧喷涂铝涂层在氯离子中的腐蚀行为

采用电弧喷涂技术在镁合金AZ91基材表面制备铝涂层.通过5(质量分数,%)NaCl溶液浸泡试验和盐雾试验,考察了镁合金表面铝涂层在氯离子中的耐蚀性能及其腐蚀行为.利用光学显微镜、扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析技术对涂层形貌、显微组织结构和相组成进行了研究.结果表明,封孔处理后的试样耐蚀性能有较大提高,未封孔的涂层试样腐蚀比原始镁合金更严重.     

Corrosion resistance of 2195 aluminum alloy treated by multi-step-heating-rate controlled process

2195 aluminum-lithium alloy was widely applied in the aviation and aerospace industry, but it is highly susceptible to pitting and intergranular corrosion undergoing sever corrosive circumstance and moisture atmosphere. To solve this problem and consequently to prolong its service life, a multi-step-heating-rate（MSRC） process was carried out. Investigations were carried out to find the effect of the MSRC process on the alloys corrosion resistance. It is found that the MSRC process is more favorable for the uniform phase precipitation by comparing the corrosion resistance of samples treated by traditional heat treatments. The potential difference between phases can be reduced and intergranular corrosion is able to be prohibited efficiently. Besides, the rare earth infiltration is beneficial to improving the corrosion resistance. As heating time increases, the corrosion resistance declines gradually, samples treated by artificial aging and solid solution also exhibit a better corrosion resistance.     

A novel dual nickel coating on AZ91D magnesium alloy

Magnesium alloys covered with metal coating display excellent corrosion resistance,wear resistance,conductivity and electromagnetic shielding properties.The electroless plating Ni-P as bottom layer following the electroplating nickel as surface layer on AZ91D magnesium alloy was investigated.The coating surface morphology was observed with SEM and the structure was analyzed with XRD.Electrochemical tests and salt spray tests were carried out to study the corrosion resistance.The experimental results indi...     

Corrosion resistance of electrodeposited RE-Ni-W-P-SiC composite coating

1　ＩＮＴＲＯＤＵＣＴＩＯＮＭａｋｉｎｇｕｓｅｏｆｃｏｍｐｏｓｉｔｅｍａｔｅｒｉａｌｓｉｓｔｈｅｄｅｖｅｌ ｏｐｉｎｇｔｒｅｎｄｉｎｔｈｅｃｕｒｒｅｎｔｍａｔｅｒｉａｌｓｓｃｉｅｎｃｅ .Ｉｔｍｅａｎｓｏｂｔａｉｎｉｎｇａｎｅｗｃｏｍｐｏｓｉｔｅｍａｔｅｒｉａｌｂｙｃｏｍｂｉｎｉｎｇｔｈｅｂｅｓｔｐｒｏｐｅｒｔｉｅｓｏｆｓｅｖｅｒａｌｄｉｆｆｅｒｅｎｔｍａｔｅｒｉａｌｓｓｏａｓｔｏｍｅｅｔｐｅｏｐｌｅ’ｓｄｅｍａｎｄｓ .Ｃｏｍｐｏｓｉｔｅｅｌｅｃｔｒｏｐｌａｔｉｎｇｉｓｏｎｅｏｆｔｈｅｍｏｓｔｕｓｅ…     

添加硅钙合金对AM60镁合金耐腐蚀性能的影响

利用化学浸泡实验法和电化学测试法研究了添加硅钙合金对AM60镁合金耐腐蚀性能的影响。结果表明,硅钙合金加入后细化了AM60合金的显微组织、形成了新的耐腐蚀相—Mg2Si相、使β-Mg17Al12相的含量增多,从而使合金的腐蚀电位正移、腐蚀电流密度和腐蚀速率降低,合金的耐腐蚀性得到有效改善。     

Zn 2.0%Al 1.5%Mg合金镀层组织结构及性能研究

采用X射线衍射分析仪（XRD）和扫描电子显微镜（SEM）研究了Zn 2.0%Al 1.5%Mg锌铝镁镀层物相、形貌及组织结构,对锌铝镁及镀锌试样进行SST、CCT耐蚀性对比试验,并测定了维氏硬度、动摩擦因数。结果表明,锌铝镁镀层主要由初生Zn相、Zn/MgZn2二元共晶组织和Zn/MgZn2/Al三元共晶组织组成;锌铝镁镀层较纯锌镀层具有良好的耐腐蚀性,同时较纯锌镀层具有较高的硬度以及较低的动摩擦因数。     

镁合金等离子喷涂Al/Al_2O_3涂层的耐腐蚀性能

采用等离子喷涂技术在AZ31镁合金表面制备Al/Al_2O_3复合涂层,测试了镁合金及表面喷涂有Al/Al_2O_3复合涂层的镁合金试样的极化曲线,研究了没有涂层、经封孔处理和未经封孔处理的喷涂有复合涂层的镁合金三种试样在浸泡腐蚀和5%NaCl盐雾腐蚀情况下的耐腐蚀性能及其腐蚀行为.结果表明,经封孔处理的Al/Al_2O_3复合涂层镁合金试样在上述腐蚀条件下的耐腐蚀性均优于镁合金和涂层未封孔处理的试样,在浸泡试验中未封孔处理的涂层试样比镁合金腐蚀更加严重,在盐雾试验中却优于镁合金.