电压对纯铝板陶瓷膜层显微组织及其性能的影响

分别采用恒定电压和阶梯电压在纯铝板表面制备陶瓷膜层,研究不同电压模式对陶瓷膜层组织和性能的影响。借助扫描电子显微镜、X射线衍射仪、显微硬度计和电化学工作站等,研究纯铝板表面陶瓷膜层的微观形貌、物相、显微硬度和耐腐蚀性能,并分析陶瓷膜层形成机理。结果表明：纯铝板表面陶瓷膜层是非晶态Al₂O₃相,与恒定电压相比,采用阶梯电压制备的陶瓷膜层孔洞、裂纹等缺陷较少。恒定电压和阶梯电压为26 V时,陶瓷膜层显微硬度均达到最大,分别为520.2 HV和570.2 HV。阶梯电压为26 V时,陶瓷膜层耐腐蚀性能最佳,自腐蚀电位和极化电阻分别为-0.429 V和113 173.9Ω。采用阶梯电压在纯铝板表面制备陶瓷膜层时,每次电压升高都会加速化学反应速率,在纯铝板表面生成致密均匀的内部阻挡层,从而提高陶瓷膜层的显微硬度和耐腐蚀性能。     

脉冲偏压对304不锈钢表面多弧离子镀CrAlN薄膜结构和耐蚀性能的影响

目前,鲜见有关脉冲偏压对多弧离子镀Cr Al N薄膜耐蚀性能影响的报道。以不同的脉冲偏压在304不锈钢表面多弧离子镀Cr Al N薄膜。采用扫描电镜、显微镜、X射线衍射仪、硬度仪、粗糙度仪分析了Cr Al N薄膜的表面形貌、相结构、硬度、表面粗糙度及耐蚀性能,分析了脉冲偏压对相关性能的影响。结果表明:随着脉冲偏压幅值的增大,Cr Al N薄膜表面大颗粒及凹坑尺寸和数量减少,薄膜质量提高;Cr Al N薄膜主要由(Cr,Al)N相组成,随着偏压增加,Cr Al N薄膜出现(220)择优取向;Cr Al N薄膜表面粗糙度随脉冲偏压增大而减小,显微硬度随脉冲偏压的增大而增大;Cr Al N薄膜在3.5%Na Cl溶液中的耐蚀性随着脉冲偏压的增大而增大,脉冲偏压为400 V时,Cr Al N薄膜与基体304不锈钢的腐蚀速率之比为0.34,薄膜的综合性能最好。     

4Cr13不锈钢表面镀TiN薄膜组织结构及性能的研究

采用多弧离子镀技术在4Cr13不锈钢上沉积TiN薄膜,在其他参数不变的条件下,研究不同弧电流下薄膜的组织、结构及性能。利用扫描电子显微镜、X射线衍射仪、显微硬度计、划痕仪和往复式摩擦磨损仪分别对薄膜进行表面形貌观察,物相分析,以及表面硬度、结合力、耐磨性检测。实验结果表明:弧电流对薄膜的表面形貌有明显的影响,随着弧电流的增大,薄膜表面的液滴数目和尺寸逐步增大;薄膜的相结构主要由TiN相组成,在(111)面有较强的择优取向,且随着弧电流的增大,衍射峰强度略有增加;随着弧电流的增大,薄膜的硬度先增大后减小,硬度值最大为2897HV;随着弧电流的增大,薄膜的结合力先增大后减小,当弧电流为105A时,薄膜的结合力最大,为75N;随着弧电流的增大,薄膜的摩擦系数先减小后增大,当弧电流为105A时,薄膜的耐磨性最好。     

金属等离子体浸没离子注入与沉积技术合成类金刚石薄膜研究

采用金属等离子体浸没离子注入与沉积技术在9Cr18轴承钢基体表面合成了类金刚石薄膜.研究了注入脉宽和工作气压对合成薄膜性能及化学组成的影响;通过激光Raman光谱、维氏硬度、针盘试验和电化学腐蚀等测试手段分别表征了合成薄膜后试样表面的化学组成和微观结构、显微硬度、摩擦磨损性能和抗腐蚀性能.结果表明:合成薄膜后,试样的显微硬度增大了88.7%,摩擦磨损和抗腐蚀性能也明显改善.     

甘氨酸对电镀镍层性能的影响

目前,国内将甘氨酸作为镀镍添加剂的研究很少。将甘氨酸作为镀镍液添加剂,研究了不同甘氨酸浓度对镀镍层微观形貌、显微硬度、耐磨性、阴极极化曲线的影响。结果表明:加入适量甘氨酸,可以得到表面结构细致平整的镀镍层。镀镍层的显微硬度随甘氨酸的浓度增加而增大。甘氨酸加入量小于3 g/L时,镀层的耐磨性随甘氨酸加量的增大而提高;镀层的磨损机理为磨粒磨损;但当甘氨酸浓度继续增加到4 g/L时,磨损过程中出现了镀层局部剥落现象,镀层的耐磨性下降。甘氨酸浓度的增加会增大镍电沉积的阴极极化程度。甘氨酸改善镀层表面形貌、提高镀层硬度的作用应该与其在镍沉积过程中增大阴极极化的能力有关。     

45钢表面大气等离子喷涂氧化钇部分稳定氧化锆热障涂层及其性能

为了制备高性能热障涂层,缩短国内外差距,在45钢表面大气等离子喷涂氧化钇部分稳定的氧化锆(YSZ)热障涂层。利用X射线衍射和扫描电镜分析YSZ涂层的相结构和微观形貌,分别测定了YSZ涂层的孔隙率、热导率、显微硬度、结合强度及隔热性能。结果表明:YSZ涂层的孔隙率、隔热温差随喷涂电压增大而减小,随喷涂距离的增加而增大;维氏硬度、结合强度和热导率随喷涂电压增大而增大,随喷涂距离增加而减小;当喷涂电压为80 V,喷涂距离为100 mm时,YSZ热障涂层的结合强度为36.78 MPa,热导率为0.705 W/(m·K),具有较好的隔热性能。     

非平衡磁控溅射氮化钛薄膜及其性能研究

采用非平衡磁控溅射技术,在钛合金(Ti6Al4V)表面沉积氮化钛薄膜。通过改变氮气和氩气分压比(PN/PAr)和基体偏压,制备出不同结构、性能的氮化钛薄膜。采用X射线衍射技术、原子力显微镜、PS-168型电化学测量系统、CSEM球盘摩擦磨损实验机、HXD-1000 knoop显微硬度仪等研究了薄膜的结构、表面形貌、耐腐蚀性能与机械性能。结果表明,采用非平衡磁控溅射技术制备出了致密的氮化钛薄膜。当PN/PAr较小时,氮化钛薄膜中存在Ti2N时,Ti2N相可以有效提高薄膜的硬度和耐磨损性能;当PN/PAr增加到0.1时,薄膜硬度达到最大,耐磨损性能最优;随着PN/PAr的继续增大,氮化钛薄膜中主要存在TiN相,氮化钛薄膜的复合硬度和耐磨损性能降低。在钛合金(Ti6Al4V)表面沉积氮化钛薄膜可以显著提高其在Hanks类体液中的耐腐蚀性能。     

射频功率对氧化铬薄膜的力学性能和耐磨损性能的影响

利用射频反应磁控溅射法在45钢基体上制备了氧化铬薄膜.采用XRD测试了薄膜的晶体结构,用Tribo-Indentor纳米力学测试系统得到了薄膜的硬度及微观形貌,在UMT显微力学测试仪上测试了薄膜的耐磨损性能,在此基础上讨论了铬靶溅射功率对薄膜的力学性能和耐磨损性能的影响.结果表明:在射频功率较低的情况下薄膜为Cr2O3结构.随着射频功率的提高,薄膜表面的大颗粒物质增多,硬度下降.射频功率增大时,磨损体积增加,薄膜的耐磨损性能下降.     

电泳-电沉积Ni-Al2O3纳米复合层的微观结构及性能

为了改善纳米复合镀层的物理、力学性能,以电泳-电沉积工艺制备了具有较高纳米Al2O3含量的Ni-Al2O3纳米复合镀层.用SEM、TEM、显微硬度计等对复合镀层的表面微观形貌、显微硬度以及耐磨性能进行了分析;探讨了电泳液中α-Al2O3微粒浓度、电沉积电流密度对复合镀层表面微观形貌、显微硬度及其与基体的结合力的影响.结果表明:α-Al2O3纳米粒子弥散分布于镀层之中,并对基质金属晶粒产生细化作用;电泳液中α-Al2O3微粒浓度对复合镀层表面微观形貌影响较大,电沉积电流密度对微观形貌无明显影响;随着电泳液微粒浓度和电沉积电流密度的增大,复合镀层显微硬度均呈下降趋势,在电泳液微粒浓度8 g/L,电沉积电流密度0.5A/dm2时,复合镀层具有最大显微硬度442 HV,较纯镍镀层有明显提高.镀层中微粒体积分数约为30％时,镀层的耐磨性能及与基体的结合性能最为优异.     

电弧喷涂法镁合金AZ31表面改性与性能研究

研究了电弧喷涂距离和喷涂电压对会展设计用AZ31合金显微形貌、显微硬度、耐盐雾腐蚀和电化学性能的影响。结果表明,在喷涂距离为120 mm、150 mm和180 mm时,随着喷涂电压的降低,表面涂层的显微硬度整体呈现先增加而后降低的趋势,在喷涂电压为28 V时显微硬度最大;在相同喷涂距离下,随着喷涂电压的下降,涂层平均腐蚀深度都在喷涂电压为28 V时取得最小值;当喷涂距离为150mm、喷涂电压为28 V时涂层的自腐蚀电位要明显高于其它电弧喷涂工艺下涂层的,是AZ31合金较为适宜的电弧喷涂工艺;采用电弧喷涂得到的涂层的自腐蚀电位相对AZ31镁合金基材发生了正向移动,耐腐蚀性能得到明显提高。     

Bias effects on the tribological behavior of cathodic arc evaporated CrTiAlN coatings on AISI 304 stainless steel

In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The coating morphology and properties including surface roughness, adhesion, hardness/elastic modulus (H/E) ratio, and friction behavior were analyzed to evaluate the impact of the substrate bias voltage on the coating microstructure and properties. The results suggest that for an optimized value of the substrate bias voltage, i.e. − 150 V, the CrTiAlN coatings showed increased Cr content and improved properties, such as higher adhesion strength, hardness, and elastic modulus in comparison to the coatings deposited by other substrate bias voltage. Moreover, the optimum coatings achieved a remarkable reduction in the steel friction coefficient from 0.65 to 0.45.     

纳米结构TiN薄膜的制备及其摩擦学性能

在室温条件下,用磁过滤等离子体装置在单晶硅基底上制备了纳米结构TiN薄膜分析了薄膜的表面形貌、晶体结构,测量了TiN薄膜的硬度,研究了基底偏压对薄膜结构性能的影响.结果表明,用此方法制备的TiN薄膜表面平整光滑,颗粒尺寸为50～80 nm;随着基底偏压的增大薄膜发生(111)面的择优取向随着偏压的提高,薄膜的颗粒度稍有增大,摩擦系数增大,偏压提高,晶面在较密排的(111)面有强烈的择优取向,硬度也有所增大.在其它条件相同的情况下载荷越大,摩擦系数越大.不起用磁过滤等离子体法制备的纳米结构TiN薄膜具有较低的摩擦系数(0.14～0.25).     

调制比对电弧离子镀Cr/TiN纳米多层膜力学性能的影响

采用电弧离子镀技术,通过改变调制比沉积Cr/TiN纳米多层膜.利用扫描电子显微镜、原子力显微镜、X射线衍射仪、纳米压痕仪研究了调制比对Cr/TiN纳米多层膜表面形貌、微观结构以及力学性能的影响.结果表明,纳米多层膜表面致密、平滑均匀,膜层与基底结合良好,膜层综合力学性能优异,出现明显的纳米效应和界面效应.当调制比为2:...     

Influence of Substrate Negative Bias on Structure and Properties of TiN Coatings Prepared by Hybrid HIPIMS Method

TiN coatings were deposited using a hybrid home-made high power impulse magnetron sputtering(HIPIMS)technique at room temperature.The effects of substrate negative bias voltage on the deposition rate,composition,crystal structure,surface morphology,microstructure and mechanical properties were investigated.The results revealed that with the increase in bias voltage from-50 to-400 V,TiN coatings exhibited a trend of densification and the crystal structure gradually evolved from(111) orientation to(200)orientation.The growth rate decreased from about 12.2 nm to 7.8 nm per minute with the coating densification.When the bias voltage was-300 V,the minimum surface roughness value of 10.1 nm was obtained,and the hardness and Young's modulus of TiN coatings reached the maximum value of 17.4 GPa and 263.8 GPa,respectively.Meanwhile,the highest adhesion of 59 N was obtained between coating and substrate.     

Deposition of TiN coatings on shape memory NiTi alloy by plasma immersion ion implantation and deposition

An investigation has been carried out to study the effect of pulse negative bias voltage on the morphology, microstructure, mechanical, adhesive and tribological properties of TiN coatings deposited on NiTi substrate by plasma immersion ion implantation and deposition. The surface morphologies were relatively smooth and uniform with lower root mean square values for the samples deposited at 15 kV and 20 kV negative bias voltages. X-ray diffraction results demonstrated that the pulse negative bias voltage can significantly change the microstructure of TiN coatings. The intensity of TiN(220) peak increased with the increase of negative bias voltage in the range of 5-20 kV. When the negative bias voltage increased to 30 kV, the preferred orientation was TiN(200). Nanoindentation test indicates that hardness and elastic modulus increased with the increase of the negative bias voltage (5 kV, 15 kV and 20 kV), and then dropped sharply at 30 kV. The adhesion between the TiN and NiTi alloy and tribological properties of TiN coated NiTi alloy depend strongly on the bias voltage parameter; the sample deposited at 20 kV possesses good adhesion strength and excellent tribological property.     

反应溅射TiN纳米晶薄膜的结构特征和耐蚀性

利用直流反应溅射技术在不锈钢和硅基体上沉积了TiN纳米晶薄膜,采用场发射扫描电镜(FESEM)、X射线衍射(XRD)和电化学阻抗谱(EIS)技术研究了薄膜的表面形貌、相结构和耐蚀性与偏压的关系。结果表明,TiN薄膜的表面结构明显取决于所施加的偏压,适当提高偏压有利于获得细小、均匀、致密和光滑的膜层。XRD分析发现,TiN薄膜为面心立方结构,其择优取向为(111)面。实验显示,对应0V和-35V偏压的薄膜为欠化学计量比的,而偏压增加至-70V和-105V时的薄膜为化学计量比的TiN。EIS结果表明,较高偏压下的TiN薄膜几乎在整个频率范围内均表现为容抗特征,其阻抗模值明显高于低偏压下的膜层,这主要与较高偏压下的薄膜具有相对致密的微结构有关。较低偏压的TiN薄膜因结构缺陷较多其耐蚀性低于基体不锈钢。EIS所揭示的薄膜结构特征与FESEM观测结果一致。可见,减少穿膜针孔等结构缺陷有利于改善反应溅射TiN纳米晶薄膜耐蚀性。     

Effects of bias voltage on the microstructure and mechanical properties of (Ti,Al,Cr)N hard films with N-gradient distributions

(Ti,Al,Cr)N hard reactive films were deposited on high speed steel substrates by multi-arc ion plating (MAIP) technology using pure Cr and Ti-50Al(at.%) alloy targets. The partial pressure of N₂ was raised step by step in each deposition process. The surface morphology, the cross-sectional morphology of fracture sample, the surface compositions and the phase structure of the (Ti,Al,Cr)N films were investigated by scanning electronic microscope (SEM) and X-ray diffraction (XRD). The dense columnar microstructure was obtained in all of the (Ti,Al,Cr)N films, though micro-droplets evidently existed on the surface of the films. The micro-hardness of the film surface, the adhesive strength of the film/substrate and the thermal shock resistance were investigated. The results revealed the effects of bias voltage on the composition, phase structure, and mechanical properties. The improved balanced properties of a micro-hardness of about 50 GPa, an adhesive strength larger than 200 N and a thermal shock resistance of 7-8 cycles were reached at a bias voltage of 150 V. The present super-hard (Ti,Al,Cr)N films with N-gradient distribution may be an actual substitution of TiN, (Ti,Al)N, (Ti,Cr)N and single-layer (Ti,Al,Cr)N hard films.     

Microstructure and Tribological Behavior of Stripe Patterned TiN Film Prepared with Filtered Cathodic Vacuum Arc Deposition (FCVAD)

This paper describes an experimental investigation into the influence of the stripe interspace and applied load on the tribological behavior of stripe patterned TiN films. The stripe patterned TiN films are deposited on an H13 steel surface by masked deposition with the filtered cathodic vacuum arc discharge (FCVAD) technique. The surface micro morphology, chemical composition, crystal structure, and mechanical properties of the films is characterized using 3D white light interferometry, scanning electron microscopy (SEM), X‐ray diffractometry (XRD), and a nano‐indentation tester, respectively. The tribological performance of patterned TiN is measured using a UMT‐5 tribometer, and the friction and wear mechanisms are analyzed, compared with that of the full TiN film and H13 steel substrate. The results show that the stripe patterned TiN films has better tribological properties than the full TiN film. These results are attributed to the synergistic effect between the surface pattern and the TiN film. The stripe interspace and the applied load has a more significant effect on the wear rate of the stripe patterned TiN films than the coefficient of friction of their friction pairs. A further study, however, is needed to analyze the relationship between the applied load and the wear rates of the stripe patterned TiN films.

     

Deposition of nano-scaled CrTiAlN multilayer coatings with different negative bias voltage on Mg alloy by unbalanced magnetron sputtering

In a magnetron sputtering system, the negative substrate bias voltage has been used as a basic process parameter to modify the deposition structure and properties of coatings. In this paper we report the effect of bias voltage ranging from −40 V to −90 V on nano-scaled CrN/TiN/CrN/AlN (CrTiAlN) multilayer coatings synthesized on a Mg alloy by a closed-field unbalanced magnetron sputtering ion plating system in a gas mixture of Ar + N₂. The technological temperature and atomic concentration in the multilayer coatings were controlled by adjusting the current density of different metal magnetron targets and the plasma optical emission monitor. The composition, crystallographic structure, deposition model and friction coefficient of multilayer coatings were characterized by X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and ball-on-disc testing. The experimental results show that the deposition model and friction coefficient of nano-scaled CrTiAlN multilayer coatings were significantly affected by the negative bias voltage (V_b). The nitride species in multilayer coatings mainly involve CrN, AlN and TiN, and XRD analysis shows that the crystallographic structure was face-centered cubic. Under different bias voltage conditions, the multilayer coating composition shows a fluctuation, and the Al and Cr concentrations respond in the opposite sense to the bias voltage, attaining their greatest values at V_b = −70 V. The surface and cross-sectional morphology shows deposition model change from a columnar model into non-columnar model with the increase in negative bias voltage. The friction coefficient of the nano-scaled multilayer coatings at V_b = −55 V stabilize after 10 000 cycles.     

钼薄膜的制备、力学性能和磨损性能

采用直流磁控溅射技术在GCr15轴承钢底材上沉积了钼薄膜。利用XRD，AFM对不同负偏压下沉积的钼薄膜的结构和表面形貌进行了表征；利用纳米压痕仪对薄膜的硬度和膜基结合强度进行了测定；最后利用DF-PM型动静摩擦系数精密测定仪和扫描电镜(SEM)研究了薄膜的硬度、残余模量与负偏压的关系。结果表明：利用直流磁控溅射法制备的钼薄膜的硬度随负偏压的变化存在最大值，另外负偏压还影响薄膜的微结构、粗糙度以及膜基结合力，但负偏压的改变对钼薄膜的摩擦系数影响不大。