Nanolayer (Ti,Cr)N coatings for hard particle erosion resistance

This paper discusses the synthesis and characterization of titanium chromium nitride ((Ti,Cr)N) thin films deposited onto AM355 stainless steel by multi-source cathodic arc physical vapor deposition (PVD) for improved erosion resistance. The effect of Cr evaporator current and substrate bias on the erosion resistance of the (Ti,Cr)N coating were investigated. The coatings were characterized using X-ray diffraction, scanning electron microscopy, electron probe microanalysis, scanning transmission electron microscopy, scratch adhesion testing and erosion testing. The (Ti,Cr)N coatings deposited using multisource mode were determined to be nanolayered structures consisting of TiN rich and CrN rich layers. EPMA showed that the atomic percentage of Cr within the coating increased (increased Cr:Ti ratio) with increasing Cr evaporator current and that the (Ti,Cr)N chemical composition did not appear to change with varying bias. Using XRD and STEM, it was determined that all nanolayer (Ti,Cr)N coatings were multi-phased consisting of a B1 NaCl crystal structure. XRD also revealed that as the Cr evaporator current was increased, there was an increase in the CrN phase volume. Macroparticle incorporation increased with an increase in Cr evaporator current and decreased with an increase in bias. The nanolayer (Ti,Cr)N coatings ranged in Vickers hardness from 1700 to 2800 VHN_0.050. Coating adhesion increased as Cr:Ti ratio increased. In regards to erosion, (Ti,Cr)N coatings with a high number of TiN/CrN interfaces performed poorly against alumina media. As the Cr evaporator current was varied, the coating deposited with the highest Cr:Ti ratio (evaporator current of 85 A) and when bias was varied, the lowest substrate bias of - 50 V had the best erosion performance.     

Ti—Al—N薄膜的性能及应用

利用多弧离子沉积技术在W18Cr4V高速钢表面沉积（Ti,Al）薄膜,实验结果表明（Ti,Al）N薄膜的硬度和抗氧化性能明显优于TiN薄膜,（Ti,Al）N膜层刀具的寿命大大高于TiN膜层刀具。     

Microstructural characterization of binary and ternary hard coating systems for wear protection. Part I: PVD coatings

Different wear-resistant coatings produced by physical vapour deposition (PVD) were characterized with the aid of cross-sectional transmission electron microscopy (XTEM). All coating systems were optimized by the producers and exhibited good properties with respect to their special applications. The microstructure, texture and chemical composition of binary and ternary systems produced by the arc process [TiN, CrN, Cr₂N (Ti, Cr)N on steel substrates] and magnetron sputtering process [TiN, CrN on steel substrates, (Ti, Al)N on Si-substrate] were investigated. All coatings had a more or less columnar microstructure, which was interrupted by interlayers in some cases. Whereas arc coatings always did show some kind of substrate modification, the latter was not observed after magnetron sputtering. Electron diffraction normally revealed a mono-phase fcc structure, except at sites very near to the interface. Only for the systems Cr–N and (Ti, Cr)–N were different additional phases observed at low nitrogen partial pressures.     

A1含量对（Ti，A1）N薄膜抗氧化性能的影响

研究了Ａ１含量对（Ｔｉ，Ａ１）Ｎ薄膜高温抗氧化性能的影响，并与ＴｉＮ薄膜进行了对比试验．试验结果表明：（Ｔｉ，ＡＩ）Ｎ薄膜的抗氧化性能明显优于ＴｉＮ薄膜；随着薄膜中Ａ１含量的增加，薄膜的抗氧化能力得到改善，特别是当氧化温度≥８００℃后效果更为显著．这是因为（Ｔｉ，Ａ１）Ｎ薄膜在高温下氧化时，在薄膜表面形成的是稳定致密的Ａ１２Ｏ３的缘故．     

Oxidation of TiN and Ti(C,N) thin films deposited on titanium substrate

Single-layered TiN and functionally graded Ti(C,N) coatings were magnetron sputtered to a thickness of about 1 μm, and their oxidation behavior was studied. The Ti(C,N) coating oxidized as fast as the TiN coating, forming TiO₂ as an oxide layer. The nitrogen in the TiN and Ti(C,N) coatings tended to escape from the coating via the TiO₂ layer into the air. The carbon in the Ti(C,N) coating also had strong tendency to escape. Even before the complete oxidation of the coatings, the retained coating layer and the Ti-substrate were strongly enriched with oxygen.     

Surface Treatment of Cr12MoV Steel towards Long-Life Cold-Work Dies

With the rapid development of the automobile industry in China, there is an ever-increasing demand for long-life cold working dies used for punching automobile components. However, the full potential of such advanced surface engineering technologies as PVD coatings and duplex surface treatments in cold work dies has not been realized. In the present study, Crl2MoV steel has been surface engineered by single PVD Ti/TiN coating and duplex treatment combining low temperature plasma nitriding (LTPN) with PVD Ti/TiN coatings. The properties of Ti/TiN coatings in terms of surface morphology, microhardness, load bearing capacity, bonding strength and wear resistance were evaluated by microhardness,scratch and wear tests. The experimental results show that PVD Ti/TiN coatings can significantly enhance the surface load bearing capacity (especially for duplex treatments) and wear resistance of Cr12MoV steel by more than one order of magnitude. This can be mainly attributed to the hard and well-adherent PVD Ti/TiN surface coatings and strong mechanical support of the LTPN sublayer. While two-body abrasive wear prevails for uncoated Crl2MoV, the micropolishing action of the counterface dominates in surface engineered material.     

Erosion performance and characterization of nanolayer (Ti,Cr)N hard coatings for gas turbine engine compressor blade applications

(Ti,Cr)N nanolayer coatings were deposited on Ti–6Al–4V, 17-4PH and Inconel 718 substrates using cathodic arc physical vapor deposition for improved erosion and corrosion resistance. Coating corrosion performance was highly dependent on the coating thickness and packing factors and correlated with increased chromium content within the (Ti,Cr)N nanolayer coatings. The change in cathode current predominantly affected coating thickness and the bias affected the packing factor. Erosion tests of the coated and uncoated substrates at both 30° and 90° erodent impingement angles were conducted using angular aluminum oxide media at particle velocities up to 145 m/s. Chromium evaporator current and substrate bias were varied to change film stoichiometry and microstructure for erosion performance evaluation. When chromium evaporator current was varied, the increase in chromium content led to an increase in binary CrN phase volume and a decrease in TiN phase volume. The increase in CrN phase volume decreased both hardness and erosion performance at both impingement angles. Lower bias values resulted in better erosion performance. At 30° erodent impingement, all coated samples outperformed the uncoated substrate; whereas, for 90° impingement, only coatings deposited at low bias values (? 25 V, ? 50 V, and ? 100 V) and high Ti:Cr ratios (> 2.4) outperformed the uncoated substrate. The primary coating failure mechanism was microchipping.     

工艺参数对高速电弧喷涂Al/1Cr13复合涂层组织结构的影响

用高速电弧喷涂制备Al/1Cr13复合涂层,采用3因素3水平正交试验法系统研究了电弧电流、电弧电压和喷涂距离对复合涂层的组织结构、孔隙率和氧含量的影响规律。采用扫描电镜对复合涂层的显微组织和孔隙率进行表征,采用氧氮含量分析仪测得涂层的氧含量。结果表明,在第9组喷涂参数即电弧电流为240A,电压为32V,喷涂距离为150mm的条件下制备的高速电弧喷涂Al/1Cr13复合涂层组织较致密,Al和1Cr13涂层的孔隙率最低分别为1.6%和2.2%。Al涂层氧含量显著低于1Cr13涂层,最低约为2%。     

Influence of Al Content on the Microstructure and Properties of the Cr Al N Coatings Deposited by Arc Ion Plating

Four Cr Al N coatings with various Al content were prepared by arc ion plating technology under different target currents.The effect of the Al content on the microstructure,chemical compositions,element chemical bonding states and mechanical properties of the Cr Al N coatings was analyzed.X-ray diffraction results show that the primary phase of the Cr Al N coating is fcc-(Al,Cr)N when the Al content is about 44.02 at.%.However,when the Al content increases to about 53.34 at.%,hcp-Al N phase emerges in the coating.And the hcp-Al N phase becomes the main phase in the Cr Al N coating with Al content of about 69.55 at.%.Cross-sectional images show that all the four coatings possess dense structures and the deposition rate of Al atom is higher than that of Cr atom.The hardness of the Cr Al N coating with Al content about 44.02 at.%is the largest(3149.72 HV)due to the solid solution hardening effect of the Al element.When the hcp-Al N phase is generated in the Cr Al N coating,the hardness declines.The tribological experiment shows that the wear resistance of the Cr Al N coating decreases gradually with increasing Al content when sliding against 100Cr6 steel ball.     

直流PCVDTi（CxN1—X）硬质膜及其应用

对不同成分的PCVD－Ti（CXN1－X）膜的组织结构及性能进行了研究。结果表明，Ti（CN）膜的高硬度、高致密组织和膜表面因吸附氧而形成的与TiN不同的表面结构是Ti（CN）膜性能优于TiN膜的重要因素。在冷挤压模上应用结果也表明，用PCVD法制备的Ti（CN）膜和TiC膜的使用效果要比TiN膜好得多。     

TiN单层和TiN/Ti(C,N)多层涂层的结构和性能研究

借助XRD、SEM、纳米压痕和划痕仪研究了采用磁控溅射在硬质合金基体上沉积的TiN单层和TiN/Ti(C,N)多层涂层的组织结构和力学性能。研究表明:TiN与TiN/Ti(C,N)多层涂层的晶粒形貌均呈柱状晶结构,而TiN/Ti(C,N)多层涂层形成了TiN、Ti(C,N)交替的调制结构。由于界面强化作用,TiN/Ti(C,N)多层涂层表现出比TiN更高的硬度及与基体更好的结合力。     

Characteristics and machining applications of Ti(Y)N coatings

The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge ion-plating method. The influence of the rare-earth element yttrium on the TiN coating properties was studied. The results show that the adhesion of the coating to the substrate were evidently enhanced by adding a small amount (0.2 wt.%) of the rare-earth element yttrium, showing a critical load of about 390 g which is much higher than that (230 g) of the TiN coating/substrate. Investigation on the corrosion resistance of the Ti(Y)N coating and the TiN coating was performed in 0.5 N Na₂SO₄ + 0.1 N H₂SO₄ + 0.1 N NaCl corrosion media by means of an electrochemical potentiodynamic polarization. The Ti(Y)N coating exhibited much better corrosion resistance than the TiN coating, whose passivity maintaining current is about one order in magnitude smaller than that of the TiN coating.The Ti(Y)N coatings deposited on some HSS-based tools were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated tools is approximately 36% higher (on the pinion shape cutters) and about 50% higher (on punch side pin) compared to that of TiN coated. The Ti(Y)N coatings showed such excellent performance. It is attributed to that the transition area of Ti(Y)N/substrate consisted of three sublayers which revealed a gradual change of phase structure and composition, so that the adhesion of the coating/substrate was evidently enhanced. Moreover, Ti(Y)N coating showed a preferred orientation with (111) plane which is favorable to improve wear resistance and corrosion resistance of the coating.     

TiN, TiN gradient and Ti/TiN multi-layer protective coatings on Uranium

Single-layer TiN, gradient TiN and multi-layer Ti/TiN coating were deposited on silicon and uranium substrates by means of arc ion plating technique. The main phase in the single-layer TiN coating was TiN with a (111) preferred orientation. Ti and TiN were observed in the TiN gradient coating and Ti/TiN multi-layer coatings. The single-layer TiN coating has demonstrated the best wear resistance among the three coatings. Compared with the bare U substrate, the corrosion potential E_corr of the multi-layer Ti/TiN coatings is increased by 580 mV, and the corrosion current density I_corr is decreased at least by two orders of magnitude. The multi-layer Ti/TiN coatings possessed the highest corrosion resistance among the three coating in a 0.5 μg/g Cl⁻ solution.     

Effects of Ti_(0.5)Al_(0.5)N coatings on the protecting against oxidation for titanium alloys

Ti0.5Al0.5N coatings were deposited on TC11(Ti-6.5Al-3.5Mo-1.5Zr-0.3Si) and silicon substrates using a cathode arc ion-plating system.The microstructure, composition, phase structure, and oxidation-resistance of the alloys and nitride coatings were investigated by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, Auger electron spectroscopy, and thermal analyzer.The results show that the oxidation resistance of the titanium alloy is relatively limited;the compound structures of Ti mixed with Al oxides are formed during the heating process.The phases of the Ti0.5Al0.5N coatings are composed of a TiN solid solution phase.The oxidation kinetics obeys the parabolic law.During the oxidation process, the selective oxidation of Al occurs, thus protecting the underlying coating and substrate.     

等离子合成TiN渗镀层组织结构及耐蚀性研究

采用等离子合成TiN渗镀层方法,在碳钢表面形成TiN沉积层＋含TiN的扩散层组织,Ti和N原子由表及里呈梯度分布,表面是均匀、致密的TiN胞状组织,显微硬度在20 GPa～25 GPa之间;沉积层与基体之间有一扩散过渡区,结合力好,无剥落现象.X射线衍射结果表明：渗镀层表面为TiN层,(200)晶面的衍射峰最强,具有明显的择优取向.将TiN渗镀试样与不锈钢1Cr18Ni9Ti和Q235钢在1 mol/L H2SO4溶液中进行电化学腐蚀对比实验表明：TiN渗镀层的耐蚀性能比不锈钢和Q235钢基体分别提高了1.4和4.2倍.      

沉积偏压对AlCrTiN纳米复合涂层力学与抗高温氧化性能的影响

沉积偏压对涂层的结构与性能具有重要影响,为研究其对AlCrTiN纳米复合涂层成分、组织结构、力学与抗高温氧化性能的影响规律,采用磁控溅射技术,改变沉积偏压(-30、-60、-90、-120 V)制备四种AlCrTiN纳米复合涂层。利用X射线衍射仪、扫描电子显微镜、纳米压痕仪等仪器表征涂层的组织结构、成分、力学性能和抗高温氧化性能。研究结果表明：不同偏压下制备的AlCrTiN纳米复合涂层均为NaCl型fcc-(Al,Cr,Ti)N相结构。随着沉积偏压增大,涂层由沿(111)晶面择优生长转变为无明显的择优生长取向,晶粒尺寸降低,残余应力和硬度增大。偏压为-90 V与-120 V时,涂层表面更加致密,具有更高的硬度和弹性模量。在800℃与900℃氧化1 h后,所有涂层表面均生成一层连续致密的Al₂O₃膜。随着沉积偏压增加,氧化膜厚度逐渐降低,表明抗高温氧化性能逐渐增强,这是因为高偏压下涂层组织更致密,且晶粒更细小。研究成果对AlCrTiN纳米复合涂层的综合性能提升与工程化应用具有一定指导意义。     

Microstructure and physical properties of PVD TiN/（Ti, Al）N multilayer coatings

Magnetron sputtered （Ti, Al） N monolayer and TiN/（Ti, Al） N multilayer coatings grown on cemented carbide substrates were studied by using energy dispersive X-ray spectroscopy （EDX）, scanning electron microscopy （SEM）, nanoindentation, Rockwell A indentation test, strength measurements and cutting tests. The results show that the （Ti, Al）N monolayer and TiN/（Ti, Al）N multilayer coatings perform good affinity to substrate, and the TiN/（Ti, Al）N multilayer coating exhibits higher hardness, higher toughness and better cutting performance compared with the （Ti, Al）N monolayer coating. Moreover, the strength measurement indicates that the physical vapour deposition （PVD） coating has no effect on the substrate strength.     

离子注入对TC4钛合金TiN/Ti涂层结合力和抗砂尘冲蚀性能的影响

目的通过离子注入提高TiN/Ti涂层的结合力和抗冲蚀性能。方法先采用金属蒸气真空弧(MEVVA)离子源在TC4基体上分别注入四种离子(Mo、Ti、Nb、Co),再用磁过滤真空阴极弧(FCVA)技术制备TiN/Ti涂层。采用非球面测量仪、AFM、XRD和纳米压痕仪,对四种离子注入的TC4基体表面粗糙度、表面形貌、物相结构、纳米硬度和弹性模量进行表征,采用划痕仪测量涂层的结合力,采用涂层冲蚀考核平台对不同试样进行砂尘冲蚀性能试验。结果经过Mo、Ti、Nb离子注入的TiN/Ti涂层的结合力和抗冲蚀性能都有提高,其中Mo离子注入的TiN/Ti涂层的结合力达71 N、耐冲蚀时间为80 min,与未离子注入涂层相比,分别增加31.5%和77.8%,而平均冲蚀率降低39.5%,仅为0.0078mg/g。Co离子注入的TiN/Ti涂层的结合力仅为40 N,平均冲蚀率增大了19.0%,达0.0433 mg/g,其抗砂尘冲蚀性能明显下降。结论离子注入涂层的抗砂尘冲蚀性能与结合力密切相关,随着结合力的增大,TiN/Ti涂层的平均冲蚀率减小,其耐冲蚀时间增加,选择合适的离子注入可提高TiN/Ti涂层的抗冲蚀性能。     

电弧离子镀CrTiN涂层的结构及耐腐蚀性能

采用电弧离子镀技术在模具钢H13表面沉积Cr_xTi_1-xN涂层,系统研究了不同Cr/Ti原子比对CrTiN合金化涂层结构、力学性能以及耐腐蚀性能的影响。结果表明:通过改变分离靶弧流实现CrTiN涂层中Cr/Ti原子比的有效调控,所制备的CrTiN涂层主要由面心立方结构(Cr, Ti)N和CrN组成,随着Cr/Ti原子比从1.1增加至1.8,涂层相结构由随机取向向(111)晶面优先生长转变。CrTiN合金化涂层显微硬度较CrN涂层得到明显提升,并随着固溶引起的晶格畸变程度变化而具有一个极大值。通过电化学阻抗谱和动电位极化曲线分析,当Cr/Ti原子比为1.4时,致密的Cr_0.59Ti_0.41N涂层具有最佳的耐腐蚀性能。     

Pulsed DC plasma enhanced chemical vapor deposited TiN/Ti(C,N) multilayer coatings

1　ＩＮＴＲＯＤＵＣＴＩＯＮＶａｒｉｏｕｓｃｏａｔｉｎｇｓｄｅｐｏｓｉｔｉｏｎｔｅｃｈｎｉｑｕｅｓ ,ｓｕｃｈａｓＰＶＤ ,ＣＶＤ ,ＰＣＶＤ ,ＩＢＥＤａｎｄＰＳＩＩｈａｖｅｂｅｅｎｕｓｅｄｔｏｉｍｐｒｏｖｅｔｈｅｗｅａｒ ｒｅｓｉｓｔａｎｃｅ ,ｃｏｒｒｏｓｉｏｎ ｒｅｓｉｓｔａｎｃｅａｓｗｅｌｌａｓｅｌｅｖａｔｅｄａｎｔｉ ｏｘｉｄａｔｉｏｎｂｅｈａｖｉｏｒｏｆｓｕｒｆａｃｅｏｆｓｔｅｅｌｓ ,ｆｏｒｉｎｓｔａｎｃｅ ,ｃｕｔｔｉｎｇｔｏｏｌｏｒｄｉｅｓｔｅｅｌｓａｎｄｎｏｎ ｆｅｒｒｏｕｓｍｅｔａｌｓｉｎ…