含Ta高温防护涂层初步研究

为了提高ＭＣｒＡｌＹ涂层的使用温度，研究了ＮｉＣｏＣｒＡｌＹＴａ涂层，并对其进行了静态氧化、循环氧化、热冲击试验和显微组织分析，结果与ＮｉＣｒＡｌＹ涂层相比，１１５０℃循环氧化寿命提高了８０ｈ，涂层中适当加入Ｔａ元素，可以使涂层使用温度提高 。     

钛基Ru-La-Ti涂层阳极的电催化性能

利用热分解法制备了不同La含量的钛基Ru-La-Ti涂层阳极，并研究了所制备涂层的电催化性能。结果表明，在Ru-Ti涂层阳极中掺杂稀土元素La可以提高涂层阳极的电催化活性，且La的掺杂量存在一个最佳范围(La的摩尔分数O．2)。涂层阳极电催化活性提高的原因在于La的引入可以提高涂层的有效活性表面积。     

喷涂功率对真空等离子喷涂羟基磷灰石涂层的影响

本文采用真空等离子喷涂设备，在不偷呐涂功率下制备了羟基磷灰石涂层，研究了热喷涂功率对羟基磷灰石涂层材料学特征的影响。实验中，使用Ｘ射线衍射仪，测定了涂层的相组成。使用扫描电子电镜，观察了羟基磷灰石涂层的表面形貌。研究结果表明，热喷涂功率对羟基磷灰石涂层的结构有着重大的影响。一方面，随着热喷涂功率的提高，涂层的非晶化加剧，涂层中非晶态的羟基磷灰石含量不断增大。另一方面，随着热喷涂功率的提高，羟基磷灰     

金属导电短纤维提高Ni涂层导电性能研究

探索了金属导电短纤维提高电磁波屏蔽用Ｎｉ涂层导电性能的机制。结果表明，金属导电短纤维能大幅度地提高Ｎｉ涂层的导电性能，经分析是由于增大涂层中导电网络的密度所致。还对复合型涂层的屏蔽效能进行了理论预测。     

反应溅射（Al，Ti）（0，N）涂层的微结构与力学性能

采用Al—Ti镶嵌复合靶在Ar、N2和O2混合气体中反应溅射制备了一系列（Al，Ti）（O，N）涂层。并采用EDS、XRD、TEM和微力学探针研究了薄膜的化学成分、微结构和力学性能。结果表明，随氧分压的提高，涂层中氧含量逐步增加，氮含量相应减少，（Al＋Ti）：（O＋N）的化学计量比仍约为1：1，涂层保持与（Al，Ti）N涂层相同的NaCl结构。低氧含量时薄膜在（111）方向上择优生长，随着氧含量的提高，涂层生长的择优取向发生改变，高氧含量薄膜样品呈现强烈（200）织构的柱状晶。与此同时，（Al，Ti）（O，N）涂层的硬度和弹性模量也仍保持在与（Al，Ti）N涂层相当的35GPa和370～420GPa的高值。由于涂层中形成了相当含量的氧化物，这类涂层的抗氧化能力有望得到提高。     

靶磁场强度对电弧离子镀沉积TiAlSiN硬质涂层内应力的影响

用电弧离子镀制备的TiAlSiN硬质涂层，具有硬度高、致密性好、结合力优良的优点，在刀具工业中有广泛的应用市场。TiAlSiN硬质涂层的内应力不仅会影响涂层的硬度和结合力，也会影响刀具的切削寿命。研究了用电弧制备TiAlSiN涂层过程中，TiSi靶的磁场强度变化对涂层内应力的影响。结果表明，当TiSi靶的磁场从MAG3调为MAG6时，磁场强度减弱，靶材离化率降低，TiAlSiN涂层的内应力从-5.84 GPa降低到-3.16 GPa，而涂层的结合力和硬度几乎没有降低，切削寿命提高了30%。研究为提高TiAlSiN涂层的性能，进而提升刀具的使用寿命提供了有价值的试验数据。     

放电等离子烧结技术制备 Ti合金表面 HA活性涂层

采用放电等离子烧结(SPS)技术，低温、快速地在Ti合金表面制备HA活性涂层。研究了涂层成分和厚度对涂层与基体结合强度的影响，观察了断口形貌。结果表明：随着涂层厚度的减小，结合强度提高；梯度涂层能提高涂层与基体的结合强度；特别是经钝化处理后烧结的试样，涂层与基体的结合强度显著提高，最高达到了64MPa，超过目前使用的生物涂层种植体材料的指标。     

喷涂功率对真空等离子喷涂羟基磷灰石涂层的影响

本文采用真空等离子喷涂设备（VacuumPlasmaSprnySystem），在不偷呐涂功率下制备了羟基磷灰石涂层，研究了热喷涂功率对羟基磷灰石涂层材料学特征的影响．实验中，使用X射线衍射仪，测定了涂层的相组成．使用扫描电子电镜，观察了羟基磷灰石涂层的表面形貌．研究结果表明，热喷涂功率对羟基磷灰石涂层的结构有着重大的影响．一方面，随着热喷涂功率的提高，涂层的非晶化加剧，涂层中非晶态的羟基磷灰石含量不断增大．另一方面，随着热喷涂功率的提高，羟基磷灰石粉末的熔化状态变好，颗粒之间的结合能力加强；涂层的显微结构明显改善．     

铝基体化学镀镍对热障涂层抗热震性影响研究

研究了铝基体化学镀镍对热障涂层抗热震性能影响，结果表明，结构相同的热障涂层，基体经化学镀镍后涂层抗热震性由原来的35次剥落失效增长到200次无明显变化，这主要是因为化学镀镍层有效减缓了热障涂层和铝基体界面位置的热应力，并大幅度提高了基体的抗氧化能力，同时热震过程中镀镍层两侧界面位置的元素扩散提高了界面结合力，涂层抗热震性提高。     

稀土与激光表面重熔对喷涂层耐蚀性的影响

针对氧化铝涂层的层状结构和多孔性特点，通过控制工作层与底层的粉末成分以及对喷涂层表面进行激光重熔等方法，实现封孔和改变原有涂层组织结构，提高涂层抗腐蚀性能。试验表明，在喷涂粉末中添加适量的稀土，或者对喷涂层表面进行激光重熔，不仅可以改变涂层的组织结构、减少或消除喷涂态氧化铝涂层中的疏松和气孔等缺陷，并且显著提高了涂层的抗腐蚀性能。     

Effects of Nano Pigments on the Corrosion Resistance of Alkyd Coating

Alkyd coatings embedded with nano-TiO2 and nano-ZnO pigments were prepared. The effects of nano pigments on anticorrosion performance of alkyd coatings were investigated using electrochemical impedance spectrum （EIS）. For the sake of comparison, the corrosion protection of alkyd coatings with conventional TiO2 and ZnO was also studied. It was found that nano-TiO2 pigment improved the corrosion resistance as well as the hardness of alkyd coatings. The optimal amount of nano-TiO2 in a colored coating for corrosion resistance was 1%. The viscosities of alkyd coatings with nanometer TiO2 and ZnO and conventional TiO2 and ZnO pigments were measured and the relation between viscosity and anticorrosion performance was discussed.     

In vivo biological responses of plasma sprayed hydroxyapatite coatings with an electric polarized treatment in alkaline solution

The plasma sprayed hydroxyapatite coatings were post-treated by an electric polarized treatment in alkaline solution (PAS). The compositions, stabilities, surface charges, bone-like apatite formation abilities of the PAS coatings were investigated. The bioactivity of the PAS coatings was characterized in vivo. The results showed that the stabilities of the PAS coatings were improved because of the increased crystallinity and the decreased impurity phase. The bone-like apatite formation abilities were also improved after the PAS treatment because of the negative charges formed on the coating surfaces. Animal experiments showed that the PAS coatings could accelerate the initial fixation of the implant. The results indicated that the PAS is a promising post-treatment method to improve the biological properties of the plasma sprayed hydroxyapatite coatings.     

Al2O3对氩弧熔覆Fe-Si金属间化合物涂层组织及性能的影响

目前Fe-Si涂层的相关研究较少。为制备Fe-Si金属间化合物复合涂层并改善其力学性能,采用氮弧.熔覆原位合成的方法在Q235钢表面制备Fe-Si涂层和Fe-Si/Al2O3金属间化合物复合涂层,利用金相电子显微镜、X射线衍射仪(XRD)、冲蚀磨损试验机、高温氧化炉等设备对涂层的显微组织、耐冲蚀磨损性能和抗高温氧化性能进行测试与分析。结果表明:Fe-Si熔覆层由Fe3Si和FeSi相构成,添加A12O3后熔覆层除存在Fe3Si,FeSi外还有AI2O3相产生;Fe-Si/Al2O3熔覆层耐冲蚀磨损性优于Fe-Si熔覆层,最高为基体的4.65倍;熔覆层的耐高温氧化性能相对基体明显提高,在800℃下Fe-Si熔覆层和Fe-Si/Al2O3熔覆层相比于基体分别提高了5.50和5.83倍。     

ZrO2纳米颗粒在Ni-ZrO2复合镀层中的分散性对镀层结构及性能的影响

研究了ZrO2纳米颗粒以单分散态和团聚态在Ni-ZrO2复合镀层中存在时,对Ni-ZrO2复合镀层结构与性能的影响.采用复合电沉积方法,分别在加有和未加有分散剂的条件下,制得了Ni-ZrO2复合镀层.扫描电镜(SEM)和X射线衍射(XRD)分析表明,利用分散剂MZS可以得到ZrO2纳米颗粒在Ni基质上均匀单分散的Ni-ZrO2纳米复合镀层.而未使用分散剂的复合镀层,ZrO2纳米颗粒在镀层中发生团聚,分散性差.ZrO2纳米颗粒在Ni-ZrO2复合镀层中的分散态不同,也将影响镀层中Ni的结晶择优取向.ZrO2纳米颗粒单分散的纳米复合镀层较ZrO2纳米颗粒团聚态的复合镀层的硬度大大提高.     

Effect of heat treatment environment on the structural characteristics and microhardness of high velocity oxy-fuel sprayed tungsten carbide-cobalt coatings

In the present study, tungsten carbide-cobalt was coated on the austenitic stainless steel using high velocity oxy-fuel spraying. The as-deposited coatings were heat treated at 750 °C in air and argon gas environments. Structural characteristics of these coatings were studied using x-ray diffraction and Raman spectrum analysis. Further, the microhardness of the polished coated samples was also evaluated. The hardness of the coatings was significantly improved after heat treatment in air and argon gas environment. However, the highest hardness was observed with the coatings treated in argon gas environment. The formation of oxide phases such as tungsten trioxide and cobalt tungstate was observed after heat treatment in the air environment, whereas under the argon environment, no oxide phases were observed.     

氧气流量对超音速火焰喷涂多尺度WC-17Co涂层组织结构与性能的影响

工艺参数对超音速火焰喷涂WC-Co涂层的组织结构、硬度、耐磨性影响较大,但相关研究较少。采用超音速火焰喷涂技术(HVOF)在4种氧气流量(322,402,482,543 L/min)下将多尺度WC-17Co粉末(含30%纳米WC和70%微米WC)喷涂在Q235钢基体表面制备WC-17Co涂层。采用扫描电镜(SEM)和X射线衍射仪(XRD)分析涂层的截面形貌和物相,测试了涂层的硬度值,通过销盘磨损试验机测试涂层的耐磨损性能,研究氧气流量对多尺度WC-17Co涂层组织结构与耐磨性能的影响。结果发现:4种氧气流量下所制备的涂层组织致密,孔隙率为0.306%~1.290%;随着氧气流量降低,涂层中WC分解更严重,当氧气流量为322 L/min时,涂层中分解相(W_2C、W和Co_3W_3C)最多;涂层的硬度随着氧气流量增加而增加,当氧气流量为543 L/min时,涂层的硬度[(933.8±29.3)HV_(3N)]是Q235钢[(183±7)HV_(3N)]的5倍;随着氧气流量增加,涂层磨损失重逐渐减小,当氧气流量为543 L/min时,涂层的磨损失重仅为(8.57±0.95)mg,耐磨损性能较基材明显提高。     

Wear of ion-plated aluminium bronze coatings under arduous metal-forming conditions

The wear of aluminium bronze coatings deposited by the ion-plating process using a slug-fed resistively heated evaporator and various discharge intensities has been studied. The coating material was Cu-14Al-4Fe alloy, which is known to have good non-galling properties in sheet metal forming. The wear and galling behaviour of the coatings were studied by a plane-on-cylinder wear test and production-scale tube-collaring experiments. Coatings improved the life of the tools, and enhancement of the deposition discharge further improved the life of the coatings.     

Corrosion behavior of nanolayered TiN/NbN multilayer coatings prepared by reactive direct current magnetron sputtering process

TiN, NbN and TiN/NbN multilayer coatings were deposited on tool steel substrates using a reactive DC magnetron sputtering process. The coatings were characterized using X-ray diffraction, nanoindentation, atomic force microscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray analysis. The corrosion behavior of TiN/NbN multilayer coatings was studied in 0.5 M HCl and 0.5 M NaCl solutions using potentiodynamic polarization and compared with single layered TiN and NbN coatings. Approximately 1.5 μm thick coatings of TiN, NbN and TiN/NbN multilayers showed good corrosion protection of the tool steel substrate and multilayer coatings performed better than single layered coatings. The corrosion behavior of the multilayers improved with total number of interfaces in the coatings. In order to conclusively demonstrate the positive effect of layering, corrosion behavior of 40-layer TiN/NbN multilayers was studied at lower coating thicknesses (32–200 nm) and compared with single layer TiN coatings of similar thicknesses. The polarization data and SEM studies of these coatings indicated that the corrosion behavior improved with coating thickness and multilayers showed better corrosion resistance as compared to the single layer coatings. Other studies such as intrinsic corrosion, effects of Ti interlayer and post-deposition annealing on the corrosion behavior of the multilayer coatings are also presented in this paper. The results of this study demonstrate that nanolayered multilayers can effectively improve the corrosion behavior of transition metal nitride hard coatings.