深振荡磁控溅射复合沉积CrN/TiN超晶格涂层的摩擦学性能

研究了IN718高温合金、WC-6%Co硬质合金和Si(100)基体上深振荡磁控溅射复合沉积CrN/TiN超晶格涂层的摩擦学性能。研究表明,涂层的生长对基体的类型没有选择性。随着基体硬度的升高,划痕结合力失效临界载荷增大,涂层结合力失效机制由翘曲失效转变为基体/涂层协同变形,未发现涂层的剥落失效。载荷为2N时,磨损机制由磨粒磨损和氧化磨损转变为轻微磨粒磨损。载荷为4 N时,IN 718基体上涂层的磨损机制为严重的氧化磨损,WC-6%Co基体上的涂层的磨损机制为磨粒磨损和氧化磨损,氧化物的产生、堆积和转移导致摩擦系数的波动。     

Tribological behavior of CrN/WN multilayer coatings grown by ion-beam assisted deposition

CrN monolayer coating and CrN/WN multilayer coatings were deposited on the silicon (100) substrate by ion-beam assisted deposition process. The bilayer period of these coatings was controlled at 8 nm and 30 nm. The cross-sectional morphology of nanoscaled multilayer coatings was characterized by scanning electron microscopy and transmission electron microscopy. The wear resistance of CrN/WN multilayer coatings and CrN monolayer coating was investigated using a pin-on-disc tribometer. The surface roughness (Ra) of the coatings was evaluated by atomic force microscopy, and that of CrN and WN monolayer coating was 6.7 and 5.9 nm, respectively. The employment of multilayer configuration in CrN/WN coating with bilayer period of 8 nm and 30 nm effectively reduced the surface roughness down to 1.9 and 2.2 nm, respectively. The friction coefficient of CrN monolayer coating and CrN/WN multilayer film with a bilayer period of 30 nm was 0.63 and 0.31, respectively. Owing to the high hardness/elastic modulus ratio, as well as the dense structure and the smooth surface roughness, the CrN/WN multilayer coatings exhibited better wear resistance in the consideration of friction coefficient and the worn surface morphology.     

不同黏度合成油下CrN/TiN多层薄膜的摩擦学特性研究

目的 探究在不同黏度合成酯润滑油的作用下,CrN/TiN多层薄膜的摩擦学性能及协同润滑机制。方法 选用聚α烯烃(PAO)与三羟甲基丙烷辛癸酸酯(TME)复配,得到不同黏度梯度的合成油。利用全自动黏度测定仪、倾点测试仪、开口闪点测定器和傅里叶变换红外光谱仪(FTIR)分别对合成油的运动黏度(40、100 ℃)、倾点、闪点和表面官能团进行表征。利用反应磁控溅射技术在316不锈钢和单晶硅片基底表面制备CrN/TiN多层薄膜。采用X射线衍射仪和FIB-TEM表征手段对薄膜的微观结构进行分析,并用纳米压痕仪和划痕仪测试了薄膜的力学性能。利用球–盘式摩擦试验机表征薄膜在干摩擦和油润滑条件下的摩擦学性能,利用XPS对摩擦实验后的磨痕元素价态进行表征。结果 CrN/TiN薄膜具有典型的面心立方结构(FCC)、异质多层结构,且其硬度可达32.2 GPa。在干摩擦条件下,与裸316基体相比,经表面镀制CrN/TiN薄膜后平均摩擦因数由0.95降至0.71,磨损深度由25.0 μm降至16.8 μm。在合成油作用下,316不锈钢-GCr15钢球(钢–钢摩擦副)、CrN/TiN多层薄膜-GCr15钢球(CrN/TiN多层薄膜–钢摩擦副)2种摩擦配副的摩擦因数和磨损率随着合成油黏度的增加均呈现降低趋势,且在同一黏度条件下薄膜试样的磨损率更低。结论 CrN/TiN多层薄膜在PAO与TME复配获得的一系列不同黏度合成油的作用下,随着合成油黏度的增加,薄膜的磨损率和磨损深度逐渐下降,其减摩抗磨性能得到显著提升。通过磨痕表面的XPS分析可知,合成油中极性的酯基吸附在滑动界面,增强了油膜的承载性能,从而减缓了对偶间的摩擦阻力。     

Microstructure and Corrosion Resistance of CrN and CrN/TiN Coated Heat-Resistant Steels in Molten Aluminum Alloy

The components of the equipment for processing the Al melts into the molded parts can be markedly corroded by the molten Al. In this study, a 4 μm CrN coating or CrN/TiN multilayer coating for providing the physical and chemical barriers between the molten reactive Al and the steel substrate were deposited by Cathodic Arc Evaporation onto 10 mm-thick heat-resistant steel plates. The dipping tests were conducted in a 700℃ A356 melt for 1 to 21 h at intervals of 3 h. The damage of the coated steel was eva...     

过滤电弧沉积的TiN/TiCrN/CrN/CrTiN多层膜

用过滤电弧技术在高速钢表面沉积了TiN／TiCrN／CrN／CrTiN多层膜，用扫描电镜(SEM)观察了截面和断口形貌及划痕后的形貌。使用俄歇电子谱仪进行剥层成分分析，用纳米压痕仪测试了多层膜和单层膜的显微硬度和弹性模量。结果表明，在调制周期大于l00nm时，多层膜的显微硬度符合Ha11—Petch关系，在80nm时，则脱离线性关系。划痕法测试多层膜的结合力达到80N。     

Microstructure evolution and surface characteristics of NiP and CrN composite coatings under phosphate glasses molding process

The NiP, CrN, NiP/CrN multilayer, and NiPCrN multicomponent composite coatings were fabricated by magnetron co-sputtering. Simulation of molding process on various coating systems was conducted against phosphate glass. The 50 mol.% P₂O₅-50 mol.% ZnO glass was chosen for the molding process due to its low glass transition temperature, T_g, around 400 °C and significant reaction at a high temperature. Phase evolution and surface characteristics of the coatings in the as-deposited and hot-pressed states were analyzed. Smooth surface morphology with a low roughness value below 5.0 nm was observed for the coatings under the hot pressing process. Grain growth and precipitation of the coatings were retarded under loading. Glass sticking behavior occurred in the NiP coating, while severe delamination of NiPCrN multicomponent composite coating was found. On the other hand, single layer CrN and NiP/CrN multilayer coatings showed superior surface and anti-sticking properties against phosphate glasses after the simulated molding process. The feasibility of NiP, CrN, and related composite coatings for phosphate glass molding is discussed.     

TiN/CrN多层薄膜微观结构与力学性能的研究

近些年来,TiN/CrN多层薄膜由于其优良的力学性能被广泛应用于表面防护,提高零部件性能和使用寿命等方面。为了研究TiN/CrN多层薄膜微观结构与力学性能的关系,本文采用磁控溅射技术制备了TiN、CrN单层薄膜和三种不同调制周期的TiN/CrN多层薄膜。通过原子力显微镜和X射线衍射分析了膜的表面形貌和相结构。使用纳米压痕仪测试薄膜的硬度和压入塑性,曲率法测定薄膜的残余应力。结果表明,TiN/CrN的多层薄膜是由TiN和Cr2N两相组成,随着调制周期的增大TiN层与CrN层之间的界面区域变小,界面平滑且明显。力学性能方面,多层薄膜的硬度和压入塑性比单层膜好,并且多层薄膜随调制周期的减小硬度和压入塑性越大,残余应力随周期性的增加而逐渐增大。综上可见,TiN/CrN多层薄膜的力学性能的改善取决于界面区域的大小和形貌,即调制周期,该结论与Hall–Petch理论相吻合。     

Microstructure and Corrosion Resistance of ON and CrN/TiN Coated Heat-Resistant Steels in Molten Aluminum Alloy

The components of the equipment for processing the Al melts into the molded parts can be markedly corroded by the molten Al. In this study, a 4 μm CrN coating or CrN/TiN multilayer coating for providing the physical and chemical barriers between the molten reactive Al and the steel substrate were deposited by Cathodic Arc Evaporation onto 10 mm-thick heat-resistant steel plates. The dipping tests were conducted in a 700℃ A356 melt for 1 to 21 h at intervals of 3 h. The damage of the coated steel was evaluated by the plane-view and cross-sectional metallography. Experimental results indicate that after certain incubation period, the coated steel was locally attacked, forming hemispherical pits on both CrN and CrN/TiN coated steels. The incubation time for the pit nucleation on the CrN coated steel was shorter than that for the CrN/TiN coated steel. Once the obvious pits formed, the pitted areas increased with dipping time, regardless of the type of coating. After 21 h of dipping, the coating that remai     

Preparation of epoxy microcapsule based self-healing coatings and their behavior

In this paper, epoxy microcapsules were prepared by interfacial polymerization of epoxy resin droplets with ethylenediamine (EDA), and the capsules were characterized by scanning electron microscope (SEM). Then, the coatings containing epoxy microcapsules were applied on carbon steels, and their behavior and self-healing effect were investigated by electrochemical impedance spectroscopy (EIS) technique and SEM observation. The experimental results demonstrate that the artificial scratches were successfully healed in about 4-h after made. Furthermore, coating prepared from 20 wt.% epoxy microcapsules shows the best performance among all the prepared coatings.     

CrN/CrAlSiN涂层海水环境下的摩擦学性能

为提高海洋装备摩擦零部件的摩擦学性能,采用多弧离子镀技术在316L不锈钢上制备了CrN/CrAlSiN涂层。通过XRD、XPS表征涂层的物相及成分,SEM和TEM表征涂层的形貌和微观结构,并用纳米压痕仪测试其硬度,采用摩擦磨损试验机对涂层在大气和海水环境中的摩擦磨损性能进行测试。结果表明:CrN/CrAlSiN涂层的微观结构主要有CrN相、AlN相以及非晶态Si_3N_4包裹CrN、AlN相,(111)择优取向最为明显;基于微观结构与CrN过渡层的设计,CrAlSiN涂层硬度高达35.5 GPa;较之于316L基底,涂层致密的结构使其在海水环境下表现出更好的耐腐蚀性能;在大气和海水环境下,CrN/CrAlSiN涂层的摩擦因数及磨损率均明显降低,在海水环境下达到最优。     

TiN、TiCN和CrN涂层在海水环境下的摩擦学性能

为提高海洋机械系统关键摩擦零部件的摩擦学性能,分别用多弧离子镀制备的TiN、TiCN和CrN涂层进行其表面防护。通过扫描电子显微镜(SEM)、能谱仪(EDS)和X-射线衍射仪(XRD)表征涂层的结构,用纳米压痕和划痕仪测试其硬度和结合力,并用UMT-3往复式摩擦磨损试验机测试涂层的摩擦磨损性能。结果表明,在海水环境中CrN涂层具有最低的摩擦因数。TiN和TiCN涂层已被磨穿,而CrN涂层在海水中最大磨痕深度为1.5μm左右,表明CrN在海水环境中具有良好的耐磨性。CrN涂层在海水中涂层的磨损率小于在蒸馏水中,说明海水的腐蚀作用在磨损过程中不明显,而海水环境良好的润滑性能起了主导作用,导致磨损率较低,这表明CrN涂层在海水环境中主要的磨损机理为机械磨损。     

Effects of intermixing process on bonding strength of IBED CrN coatings

1　ＩＮＴＲＯＤＵＣＴＩＯＮＨｉｇｈｅｎｅｒｇｙｐａｒｔｉｃｌｅｓｒｅｃｏｉｌｉｎｇｉｓｕｓｕａｌｌｙｕｓｅｄｔｏｓｔｒｅｎｇｔｈｅｎｔｈｅｉｎｔｅｒｆａｃｅｉｎｏｒｄｅｒｔｏｉｎｃｒｅａｓｅｔｈｅｃｏａｔ ｉｎｇ ｓｕｂｓｔｒａｔｅａｄｈｅｓｉｏｎ ｐｒｏｐｅｒｔｙ[1,2 ].Ｂａｓｉｃａｌｌｙ ,ｔｈｅＩＢＥＤ (ｉｏｎｂｅａｍ ｅｎｈａｎｃｅｄｄｅｐｏｓｉｔｉｏｎ)ｉｎｔｅｒｍｉｘｉｎｇｐｒｏｃｅｓｓｉｎｇｉｎｃｌｕｄｅｓｄｙｎａｍｉｃｒｅｃｏｉｌｍｉｘｉｎｇ (ＩＤＲ)ａｎｄｓｔａｔｉｃｒｅｃｏｉｌｍｉｘ…     

TiN及TiSiN涂层在海水环境下的摩擦学行为研究

目的对比研究海水环境下Ti N及Ti Si N涂层与Al2O3对磨的摩擦磨损行为。方法采用多弧离子镀技术在316L不锈钢及单晶硅片上制备Ti N及Ti Si N涂层。利用场发射扫描电子显微镜(SEM)、X射线衍射仪(XRD)及X射线光电子能谱仪(XPS)分析了涂层的截面形貌及化学组织成分。选择纳米压痕仪测量了Ti N及Ti Si N涂层的硬度及弹性模量,使用UMT-3往复式摩擦试验机研究了人工模拟海水环境下Al2O3与Ti N及Ti Si N涂层对磨后的摩擦磨损行为,并采用扫描电镜(SEM)、电子能谱(EDS)及表面轮廓仪来深入分析了磨痕的摩擦磨损情况。结果研究表明,Ti N涂层的硬度为32.5 GPa,当Si元素掺入涂层以后,Ti Si N涂层的硬度提高到了37 GPa。同时,较之于Ti N涂层,Ti Si N涂层的腐蚀电流密度下降了一个数量级。在摩擦实验中,Ti N涂层的摩擦系数和磨损率分别为0.35和5.21×10-6 mm3/(N·m),而Ti Si N涂层的摩擦系数和磨损率均有明显下降,分别为0.24和1.96×10-6 mm3/(N·m)。结论 Si元素掺杂后能显著提高Ti N涂层在海水环境下的摩擦学性能,主要归因于结构的致密,硬度、韧性、抗腐蚀性的提高及润滑相的形成。     

CrN和CrAlN涂层热稳定性、力学和摩擦学性能研究

目的 针对现有刀具用硬质CrN及CrAlN涂层的热稳定性研究尚属空白,以及对其涂层摩擦学性能的影响尚不清楚等问题,开展CrN和CrAlN涂层的热稳定性、氧化行为、力学性能及摩擦磨损性能研究。方法 采用中频反应磁控溅射技术制备CrN和CrAlN涂层,利用真空热脱附系统、场发射扫描电镜、原子力显微镜、能谱仪、X射线衍射、拉曼光谱仪、纳米压痕仪和摩擦磨损试验机等探究2种涂层的结构、热稳定性、力学性能和摩擦学性能。结果 在真空温度为646 ℃左右时,CrN涂层开始发生N分解和释放,在885 ℃左右时N的释放速率达到峰值。CrAlN涂层在真空温度为722 ℃左右时才开始发生N分解和释放,而在1 000 ℃下N的释放速率并未达到峰值。在大气温度600 ℃下,CrN涂层开始发生氧化,并生成Cr2O3相,且Cr2O3层的厚度随着温度的升高而增加,在900 ℃时涂层完全氧化。CrAlN涂层在900 ℃时才开始发生氧化,生成更为致密的Cr2O3和Al2O3混合氧化层,阻止涂层进一步氧化。在大气高温条件下,CrAlN涂层均具有比CrN涂层更高的硬度和弹性模量。随着温度的升高,2种涂层的表面粗糙度逐渐增加,摩擦因数逐渐降低,CrAlN涂层在600、800 ℃下的表面粗糙度和磨损率均低于CrN涂层。结论 在真空下,CrAlN涂层中键能较高的Al-N共价键改善了涂层的热稳定性,提高了CrAlN涂层中N的分解温度。在大气中,CrAlN涂层具有比CrN涂层更高的抗氧化性、硬度和弹性模量,CrAlN涂层在高温氧化过程中生成了连续且致密的Cr2O3和Al2O3混合氧化层,能够减缓O原子向涂层内部的扩散。CrAlN涂层具有比CrN涂层更优异的耐磨性,更适合作为高温工况下服役的刀具和模具等易磨损材料的防护涂层。     

深振荡磁控溅射复合沉积CrN/TiN超晶格薄膜的结构和性能研究

本文分别采用深振荡磁控溅射(Deep Oscillation Magnetron Sputtering, DOMS)复合脉冲直流磁控溅射(Pulsed dc Magnetron Sputtering, PDCMS)技术和单一的PDCMS技术,沉积厚度为2 mm、调制周期为6.3 nm的CrN/TiN超晶格薄膜。利用XRD、SEM和TEM表征薄膜的结构。利用纳米压痕仪、划痕仪和空气电阻炉分别测试薄膜的力学性能、结合力和热稳定性。利用球-盘式摩擦磨损试验机测试薄膜的摩擦学性能。利用阳极极化实验测试薄膜在3.5 wt.% NaCl溶液中腐蚀性能。研究表明,与单一的PDCMS技术相比,DOMS+PDCMS复合技术显著改善了CrN/TiN超晶格薄膜结构,薄膜具有更优异的力学、持久的耐磨减摩和抗腐蚀综合性能。     

20CrMo上沉积CrN涂层的力学性能及5W/40润滑下的摩擦学性能

在活塞销材料(20CrMo)上沉积了5种不同厚度的CrN涂层,研究其力学性能及发动机油5W/40润滑下的摩擦学性能。分别对CrN涂层的表面形貌、截面厚度、硬度、弹性模量和高温膜基结合性能进行了测试。探讨了不同接触压力和不同转速下CrN涂层与锡青铜(QSn7-0.2)配副以及基材20CrMo与QSn7-0.2配副在5W/40润滑下的摩擦学性能差异,并分析了接触电阻。结果表明:涂层沉积厚度对CrN涂层的硬度等力学参数的影响较小,但对高温膜基结合性能的影响较大。在5W/40润滑下,CrN涂层与QSn7-0.2配副在接触压力较大或较小的大部分区域都具有相对较低的摩擦因数,且磨损体积极小。     

Microstructure and tribological properties of CrN and CrSiCN coatings

Three CrN based coatings were deposited on 17-4PH precipitation hardening stainless steel substrate using plasma enhanced magnetron sputtering (PEMS) technique. The three coatings evaluated in this study assumed the nominal compositions of Cr_0.68N_0.32 (sample CrN), Cr_0.55Si_0.013C_0.14N_0.3 (sample CrSiCN-1), and Cr_0.43Si_0.034C_0.25N_0.29 (Sample CrSiCN-2)_. The microstructure, mechanical properties and wear and erosion resistance of the coatings were evaluated to examine the effect of Si and C additions to CrN. The results indicated that with the incorporation of Si and C, the microstructure transformed from hexagonal Cr₂N (for CrN coating) to B1 structure containing crystalline Si₃N₄ (for CrSiCN-2). The initial addition of Si (1.3 at.%) and C resulted in increase of hardness (H), Young's modulus (E) and the ratio of H³/E². With further increase in Si (3.4 at.%) and C, the hardness and Young's modulus decreased. The coefficient of friction was observed to decrease with the addition of Si and C, irrespective of microstructure changes. The combination of reduced coefficient of friction and microstructure modifications has resulted in improved wear resistance for sample CrSiCN-2 (with a wear rate ∼ 60% lower than CrN). The erosion resistance test results showed brittle erosion characteristics for samples CrN and CrSiCN-1 where erosion rate increased with erodent impingement angle and reached the highest rate at 75° and 90°, respectively. CrSiCN-2 coating, while exhibiting higher erosion rate at low impingement angle, demonstrated reduced erosion rate at higher angle due to the ductile nature of the coating under erosion test condition.     

Structure of duplex CrN/NbN coatings and their performance against corrosion and wear

In tribological applications the coating-substrate combination can be considered as a system, since both greatly influence the properties of that affect the tribological performance. Further, it is often desirable that both high wear resistance and corrosion resistance can be achieved even when low cost and easily machineable substrate materials are considered. Duplex surface treatment combining pulse plasma nitriding and PVD coating can provide solution for excellent wear and corrosion resistance for low alloy and constructional steels.In this work three different pulse plasma nitriding processes were carried out prior to the CrN/NbN PVD coating to attain high surface hardness and enhanced load bearing behaviour for S154 high strength construction steel. The phase composition of the compound layer, formed in the nitriding process, was found to greatly affect the tribological properties of the duplex system. The compound layer with high amount of ?-phase contributed to superior corrosion and wear resistance, whereas the ductile γ'-phase compound layer provided better impact resistance and enhanced. The best duplex treated S154 samples had wear resistance comparable to that of similarly coated HSS. The corrosion resistance was also improved by duplex process. If anodic current at + 500 mV vs. SCE is considered as criteria, the best system has almost 3 orders of magnitude lower corrosion current than with the PVD coating alone.     

Tribological behavior and wear mechanisms of TiN/TiCN/TiN multilayer coatings

This work employs the PVD process to deposit coatings of single layer TiN, binary layer TiN/TiCN, multilayer TiN⇔⇔N, and sequenced TiN⇔CN⇔N multilayer coatings with variable individual TiN-layer and TiCN-layer thicknesses on tungsten carbide disks and inserts. Also investigated are the fracture mechanisms and the influence of sequence and thickness of these coatings on cylinder-on-disk, line-contact wear mode and ball-on-disk, point-contact wear mode through SRV reciprocating wear tests. Actual milling tests identify wear performance. Experimental results indicate that the coating with a total thickness of 7 Μm and layer sequence TiN/TiCN/TiN exhibits good wear resistance on SRV wear test and milling test. The thickest multilayer TiN/Ti/TiN coating, although having the highest hardness, has the worst wear resistance for all tests. No-tably zero-wear performance was observed for all coating disks under cutting fluid lubricated condition due to the transferred layers formed between the contact interface.     

The corrosion behavior of TiN coated and uncoated incoloy 800 alloy

Incoloy alloy 800 is used in a variety of applications in industry as well as in domestic appliances for sheeting on electric heating elements. The composition of the alloy enables it to resist deterioration in many corrosive environments. However, resistance of the alloy to corrosion in aqueous media needs to be further examined. The present study examines the corrosion properties of Incoloy 800 alloy of both coated and uncoated workpieces obtained in a 0.1N H₂SO₄ + 0.05N NaCl solution. TiN coating is achieved using a physical vapor deposition (PVD) technique while corrosion tests are carried out using electrochemical polarization methods. Moreover, in order to examine the influence of hydrogen diffusion, reduction of hydrogen at the Incoloy 800 surface is carried out in a solution of 0.1N HNO₃ + 1 g/L thiourea. Tensile tests are conducted on the workpieces to determine the influence of hydrogen embrittlement on the resulting mechanical properties of the substrate. To examine the pit formation and stress induced microcracking, scanning electron microscope (SEM) analysis is carried out. The results show that the corrosion resistance of the alloy improves after TiN coating. In addition, no specific pattern or differentiation on the pit geometry is observed. The pitting rate and its size reduce considerably for TiN coated workpieces.