Tribological Behavior of Ni-P Deposits on Dry Condition

采用化学镀的方法,调整Ni-P化学镀工艺参数及使用热处理工艺,获得了不同微观结构的镀层。并使用电子探针,XRD,显微硬度测试仪及摩擦磨损试验仪研究了镀层性能。结果表明,增加镀层纳米相含量可以提高镀层的显微硬度,其值可以达到400℃热处理时的硬度。强化机理包括固溶强化和析出强化,这取决于镀层中的磷含量和热处理温度。进一步的摩擦磨损实验结果表明,纳米相含量高的镀层在400℃热处理前后均表现出较好的显微硬度以及较低的摩擦系数,具有良好的抗磨损能力。     

干摩擦条件下Ni-P镀层的摩擦学行为(英文)

采用化学镀的方法,调整Ni-P化学镀工艺参数及使用热处理工艺,获得了不同微观结构的镀层。并使用电子探针,XRD,显微硬度测试仪及摩擦磨损试验仪研究了镀层性能。结果表明,增加镀层纳米相含量可以提高镀层的显微硬度,其值可以达到400℃热处理时的硬度。强化机理包括固溶强化和析出强化,这取决于镀层中的磷含量和热处理温度。进一步的摩擦磨损实验结果表明,纳米相含量高的镀层在400℃热处理前后均表现出较好的显微硬度以及较低的摩擦系数,具有良好的抗磨损能力。     

等离子喷涂Al2O3涂层与高硬配副的摩擦学性能研究

目的 研究大气等离子喷涂Al2O3涂层在高硬配副下的摩擦磨损行为.方法 通过大气等离子喷涂(APS)制备了厚度约为380μm的Al2O3涂层,利用纳米压痕仪测量了Al2O3涂层和两种摩擦副的硬度和弹性模量.采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)对喷涂粉末、涂层以及磨痕的相结构和形貌进行了表征分析,通过X射线能量色散谱仪(EDS)分析了涂层磨痕中对偶元素的转移.另外,还通过CSM摩擦机系统地研究了该涂层的摩擦磨损行为.借助X射线光电子能谱仪(XPS)分析了磨痕中的化学组成.结果 制备的Al2O3涂层主要以γ-Al2O3相为主,且存在一定孔隙,并出现层状结构.在摩擦实验中发现,在同一摩擦副下,Al2O3涂层的摩擦系数随着载荷的增加而逐渐降低,磨损率随之增大.由于摩擦配副力学性能的差异,使Al2O3涂层表现出不同的摩擦磨损行为.以Si3N4为摩擦副时,Al2O3涂层的摩擦系数较小,但磨损率大,磨损机制主要是磨粒磨损和粘着磨损.在摩擦过程中,Si3N4对偶副会与空气中的水反应,生成少量具有润滑效果的Si(OH)4胶体.以WC为摩擦副时,Al2O3涂层的摩擦系数大,但磨损率低,磨损机制主要是粘着磨损和磨粒磨损,并伴有疲劳磨损.在摩擦过程中,由于产生了摩擦热,Al2O3涂层磨痕表面的γ-Al2O3相转变为 α-Al2O3相,摩擦配副的硬度和弹性模量越大,摩擦系数越高,γ-Al2O3相的转变也越多.结论 因高硬度的Si3N4和WC对偶球拥有不同的力学性能,对大气等离子喷涂制备的Al2O3涂层的摩擦磨损机理有显著的影响,并且在摩擦过程中,涂层磨痕内的γ-Al2O3相会向α-Al2O3相转变.     

刀具表面沉积的CrMoN渗/镀复合涂层的微观结构和力学性能

采用闭合场非平衡磁控溅射离子镀(CFUMSIP)技术和离子渗氮技术在M2工具钢表面沉积CrMoN渗/镀复合涂层。利用SEM、EDS、XRD、纳米压痕仪、划痕仪和销盘摩擦磨损试验仪研究了该涂层的组织、成分、相结构、硬度、膜/基结合强度和摩擦磨损性能。结果表明,该涂层的表面和截面致密,涂层呈柱状晶生长,为fcc结构,同时图谱中出现了γ-Fe_4N和α-Fe的衍射峰。CrMoN渗/镀复合涂层的膜/基结合强度和摩擦磨损性能明显优于单一制备的CrMoN涂层。     

第三组元铝元素对TaMo高温合金涂层组织和性能的影响

通过磁控溅射法在硅基材上制备了不同基底温度的TaMo和TaMoAl涂层,用原子力显微镜（AFM）和X射线衍射仪（XRD）研究了加入第三组元Al元素的情况下,TaMo涂层的表面形貌和组织结构,用显微硬度计和划痕试验仪测试了涂层的显微硬度和膜基结合力等力学性能。结果表明,两种基底温度工艺下铝元素的加入对TaMo涂层的组织结构和表面形貌均有显著影响。另外,在350℃的基底加热工艺下铝元素的加入提高了TaMo涂层的显微硬度和膜基结合力。     

Si对Ti-Al-Si-N涂层微观结构及性能的影响

Ti-Al-Si-N涂层是在Ti-Al-N涂层基础上发展而来的一种四元复合涂层。本文综述了Si对Ti-Al-Si-N涂层微观结构、硬度、残余应力、抗氧化性能、热稳定性能、摩擦磨损性能及切削性能的影响。分析表明:Si元素能有效细化晶粒,减少柱状晶,形成新型纳米结构,从而显著提高涂层硬度,可达39 GPa;Si的原子分数超过5%后,涂层残余应力逐渐降低;Ti-Al-Si-N涂层在1 100℃下仍具有良好的抗氧化性能;Si元素使涂层的热稳定性能有很大提高,Ti-Al-Si-N涂层1 100℃氧化后硬度无显著变化;与Ti-Al-N涂层相比,添加Si元素后涂层的摩擦系数由0.7下降至0.5;Ti-Al-Si-N涂层刀具的使用寿命与Si原子分数有很大的关系。     

氮气分压对AlCrTiSiN超晶格涂层微观结构及力学性能的影响

超晶格涂层因具有优异的力学性能及抗氧化性能在刀具涂层工业中备受关注。采用多弧离子镀技术在高速钢表面制备了AlCrTiSiN涂层,研究了氮气分压对AlCrTiSiN涂层微观结构及力学性能的影响。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和原子力显微镜研究了AlCrTiSiN涂层的微观结构;利用纳米压痕仪、划痕仪和磨损仪研究了AlCrTiSiN涂层的力学性能。结果表明:不同氮气分压的AlCrTiSiN涂层均由(Cr,Al)N相、(Ti,Al)N相和(Cr,Al)2N相以及非晶态的Si相和Si3N4相组成。与氮气分压为4Pa的涂层相比,氮气分压为2或3Pa的涂层具有更高的硬度、抗载荷能力和涂层-基体结合强度,以及更低的摩擦因数及磨损率。此外,45钢和铸铁切削试验表明:AlCrTiSiN涂层刀具较AlCrN涂层刀具有更好的切削性能,无涂层刀具具有最差的切削性能。     

电火花沉积制备Fe-8B-Mo非晶涂层的可行性

为研究Fe-8B-Mo合金的非晶形成能力,采用电火花沉积工艺制备了4种Fe-8B-x Mo(x=13.62,23.62,33.62和43.62,w/%)合金涂层。通过X射线衍射仪(XRD)表征涂层的物相组成,探索获得非晶涂层的可行性,并采用扫描电镜(SEM)、显微硬度测试及摩擦磨损试验进一步研究所得涂层的微观组织与性能。结果表明:4种涂层都由非晶相、马氏体相和Fe2B相组成,其中,13.62%Mo涂层主要含Fe2B相和马氏体相,而23.62%Mo、33.62%Mo和43.62%Mo涂层主要含非晶相,且随着Mo含量的增加,涂层中非晶相含量逐渐减少。4种涂层的组织结构致密,缺陷少,与基体呈良好的冶金结合。23.62%Mo涂层具有最大的峰值显微硬度(1 138.1 HV0.05);同时,该涂层在摩擦磨损的稳定阶段具有最小的平均摩擦因数,且其2 h的磨损质量也最小,表现出更好的摩擦磨损性能。4种涂层的磨损机制均为磨粒磨损和疲劳磨损。     

电火花沉积碳化铬基金属陶瓷涂层的微观组织与性能

采用电火花沉积分别制备了碳化铬基金属陶瓷单涂层和碳化铬基金属陶瓷/Ni复合涂层。采用X射线衍射仪(XRD)、扫描电镜(SEM)、显微硬度计和摩擦磨损试验机对比研究了单涂层和复合涂层的物相、微观组织结构、显微硬度和摩擦磨损性能。结果表明,两种涂层组织结构致密,与基体呈良好的冶金结合,并在涂层内形成了纳米晶的微观组织。复合涂层中FeCr_(0.29)Ni_(0.16)C_(0.06)韧性相含量增加,在涂层界面处存在过渡层Ni,并以塑性变形的方式释放了更多沉积时产生的热应力,因而涂层裂纹明显减少。复合涂层的峰值硬度(11.86 GPa)虽略低于单涂层,但该涂层具有最小的摩擦系数(0.2462),1 h磨损量仅为单涂层的1/3,因此表现出更好的耐磨性能,其主要磨损机制为磨粒磨损和疲劳磨损。     

Ti靶电流对CrTiAlN涂层摩擦磨损性能的影响

在不同Ti靶电流下,采用非平衡磁控溅射技术在SDC99冷作模具钢表面制备CrTiAlN涂层。采用X射线衍射仪、原位纳米力学测试系统和摩擦磨损试验机等测试分析了Ti靶电流对涂层的相结构、力学性能及摩擦磨损性能的影响。结果表明:随着Ti靶电流的增加,涂层的厚度及Ti含量呈非线性增加,涂层的纳米硬度与弹性模量分别增至26.08与302.86 GPa,Cr(Ti,Al) N涂层均为单相fcc结构;在Ti靶电流4 A下沉积的涂层的摩擦磨损性能最好,干摩擦因数和磨损率分别为不含Ti涂层的69.77%和65.31%;油磨26 h后磨损率为不含Ti涂层的25.67%,磨损机制为磨粒磨损与疲劳磨损的综合。     

Si含量对多元等离子体浸没离子注入与沉积技术制备TiAlSiN涂层微结构和机械性能的影响(英文)

采用多元等离子体浸没离子注入与沉积制备TiAlSiN纳米复合涂层,利用EDX,XRD,SEM,XPS,纳米探针和划痕试验对涂层成分组成、微结构和机械性能进行测试分析。XRD测试表明,TiAlSiN涂层具有较强的TiN(200)择优取向。XPS测试表明,TiAlSiN涂层中也含有AlN、Si3N4、Al2O3和Ti2O3。与制备的TiN涂层相比,当涂层中的Si含量为0.9%时,TiAlSiN涂层表现出较高的硬度,达32GPa,但涂层的断裂韧性和结合强度较低;当涂层中的Si含量增加至6.0%时,TiAlSiN涂层具有超高的硬度57GPa,并表现出较好的断裂韧性和结合强度。     

Microstructure and tribological properties of diamond-like carbon and TiAlSiCN nanocomposite coatings

Diamond-like carbon (DLC) and TiAlSiCN nanocomposite coatings were synthesized by multi-plasma immersion ion implantation and deposition. The DLC content in the composite coating was controlled by the flow ratio of N₂ to C₂H₂ during the deposition process. The microstructure and tribological properties of the as-deposited coatings were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), nanoindentation and ball-on-disk friction tests. The TEM results show that all the DLC-TiAlSiCN coatings had a two phase composite structure of the TiCN nanocrystals embedded in an amorphous matrix consisting of a-Si₃N₄, a-SiC, a-CN and DLC. TEM observations also reveal that the spacing between the adjacent nanocrystals increases with DLC content. In addition, the DLC-TiAlSiCN nanocomposite coating with a small crystalline spacing of about 0.6 nm shows a higher hardness up to 50 GPa and a larger friction coefficient. An increase in the DLC content of the coating benefits its friction coefficient while its hardness decreases. The friction coefficient reduces to 0.14 when the DLC content is about 31%.     

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.     

磁控溅射沉积V-Al-N涂层的结构和性能研究

通过反应磁控溅射法制备了V1-xAlxN(0≤x≤0.67)涂层,研究了Al含量对涂层微观结构、力学性能及摩擦磨损性能的影响.结果表明:在0≤x≤0.51范围内,随Al含量的增加,V1-xAlxN涂层的微观结构不断变得致密,硬度不断提高,其中结构最为致密的V0.49Al0.51N涂层的硬度较VN提高了近3倍;在较宽的成分区间内,V1-xAlxN涂层结构均比较致密,硬度大于30 GPa,最高硬度达到41 GPa;随着硬度的改善,V1-xAlxN涂层的摩擦磨损性能较VN涂层也有不同程度的提高.     

同步脉冲偏压对HiPIMS技术低温沉积CrN涂层结构及性能影响*

针对高性能 CrN 涂层无法实现低温可控制备的技术瓶颈,利用具备高溅射材料离化率的高功率脉冲磁控溅射技术,调控同步脉冲偏压,改善涂层生长动力学条件,实现 CrN 涂层的低温可控沉积。开展同步脉冲偏压与涂层化学组成、组织结构、 力学、摩擦学及耐腐蚀性能间关联关系研究。同步脉冲偏压在提升沉积离子束流迁移能的同时可显著降低荷能 Ar⁺ 对成膜表面的持续轰击作用,达到改善涂层致密性及膜基结合力的目的。此外,沉积 CrN 涂层晶粒细化显著,硬度及弹性模量明显升高,最高可达 13.8 GPa、236.7 GPa。涂层力学性能优化及致密性提升显著改善了摩擦学与耐腐蚀性能,涂层磨损率最低可达 2.49×10^?15 m³ / (N·m),同时涂层可耐受 120 h 中性盐雾腐蚀环境考核。为实现高性能 CrN 涂层的低温可控制备,扩展其在温度敏感基体领域的适用范围提供了新的设计思路与技术支撑。     

等离子喷涂制备石墨烯/Al2O3+13%TiO2自润滑涂层及其性能研究

目的研究石墨烯和石墨对大气等离子喷涂制备的Al2O3+13%TiO_2(AT-13)陶瓷涂层力学性能和摩擦学性能的影响,探究作用机理。方法采用大气等离子喷涂制备石墨烯质量分数为1%的石墨烯/AT-13和石墨/AT-13复合陶瓷涂层及纯AT-13涂层,利用洛氏硬度计测试涂层的硬度,并通过压痕周围情况反映涂层的断裂韧性,采用往复式摩擦磨损试验机进行摩擦学性能测试,利用扫描电子显微镜观察涂层的微观形貌,并用其自带的能谱仪(EDS)分析元素分布,采用表面轮廓仪测量磨损表面形貌并计算磨损率,用X射线衍射仪分析喷涂前后涂层的物相变化,用拉曼光谱仪对喷涂前后石墨烯的结构变化进行表征。结果石墨烯/AT-13涂层具有良好的力学性能和摩擦学性能,其硬度提升了约10%,同时断裂韧性显著提升,摩擦系数和磨损率最多下降了13%和19%,并且随着载荷的增大,摩擦系数和磨损率呈下降趋势。石墨/AT-13涂层的硬度增加了约30%,但是断裂韧性显著降低,摩擦学性能的提升比较有限。石墨烯和石墨的加入都会改变AT-13涂层的物相组成和微观结构,复合涂层中Al2O3相增多,Al2Ti O5相则相对减少,同时复合涂层拥有更加致密的微观结构。此外拉曼光谱显示,经历热喷涂后,涂层中能够观察到石墨烯特征峰的存在,但是其结构发生了一定程度的氧化破坏。结论石墨烯可以显著提升AT-13涂层的摩擦学性能和力学性能。     

TRIBOLOGICAL AND HIGH SPEED TURNING PERFORMANCE IN Ti1-xAlxN COATINGS PREPARED BY CLOSE-FIELD UNBALANCED MAGNETRON SPLTTERING

Titanium-aluminium-nitride (Ti1-xAlxN) coatings were deposited by close-field unbalanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 450℃. The tribological behavior was analyzed by sliding against steel and WC-6wt%Co balls, while the turning performance was evaluated by a conventional turning machine at high cutting speeds without using coolants. In the tribological tests, the formation of transfer layer and the variations of hardness of the coatings played an important role for sliding against steel balls. For the coatings sliding against WC-6wt%Co balls, the Ti-Al-N coatings showed a similar friction coefficient, but the TiN coating exhibited a lower value. The difference could be explained by the tri-oxidation wear mechanism. In the turning tests, a superior cutting performance of the coating was found at x=0.45, which endured 38 minutes before the tool flank wear reached the maximum value of 0.3mm, whereas only 20 minutes were endured for the TiN coating. The excellent performance of the coatings in the turning tests could be explained by the enhanced mechanical properties and oxidation/diffusion resistance of the coatings.     

Correlation of crystallization behavior and mechanical properties of thermal sprayed PEEK coating

An amorphous PEEK coating was prepared on an Al substrate by a flame spraying process. The amorphous coating was subjected to an annealing treatment under an annealing temperature from 180 to 300 °C and a holding time from 1 to 30 min. The cold crystallization behavior of the as-sprayed coating differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD) measurements. The hardness and tribological behavior of the coatings were investigated. Both DSC and WAXD analysis revealed that the annealed coatings exhibited a semi-crystalline structure. Coexistence of double crystal entities in annealed coatings was deduced. The annealed coatings exhibit higher hardness, lower friction coefficient and wear rate. Both the annealing temperature and holding time can benefit the coating hardness. The annealing condition in the studied range has little influence on the tribological behavior of the coatings. The variances of the coating mechanical properties were correlated with the modifications of the coating structures induced by the annealing treatments.     

钛合金表面激光熔覆AlBxCoCrNiTi高熵合金涂层的组织与性能

目的研究AlB_xCoCrNiTi(x=0、0.5、1)高熵合金涂层的组织及性能,提高钛合金表面硬度及耐磨性。方法采用激光熔覆技术在TC4钛合金表面制备出AlB_xCoCrNiTi高熵合金涂层,运用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、电子探针(EPMA)等材料分析手段,研究了B含量对高熵合金涂层形貌、组织结构、成分的影响,并采用维氏硬度计以及摩擦磨损试验检测了熔覆涂层的硬度和耐磨性能。结果高熵合金涂层与基体的整体结合形貌良好。未添加B的高熵合金涂层主要由BCC相和晶体结构类似(Co,Ni)Ti_2相组成。随着B的加入,高熵合金涂层的晶粒得到细化,BCC相含量增加,(Co,Ni)Ti_2相含量有所减少,且熔覆层原位生成了TiB_2硬质相,TiB_2硬质相含量随B含量的增加而增加。熔覆涂层的硬度和耐磨性与B含量呈正相关关系,AlB_1CoCrNiTi高熵合金涂层的平均显微硬度最大,为814HV,且AlB_1CoCrNiTi高熵合金涂层的磨损量最小,其耐磨性约为未添加B的高熵合金涂层的7倍。结论 B含量的增加,有助于改善AlB_xCoCrNiTi高熵合金涂层的摩擦学性能,AlB_xCoCrNiTi高熵合金涂层有效提高了钛合金表面的硬度及耐磨性能。     

Mechanical and tribological evaluation of PVD WC/C coatings

Five different WC/C coatings deposited by physical vapour deposition (PVD) on high speed-steel (HSS) have been evaluated with respect to their mechanical and tribological properties. For all coatings a chromium layer was deposited first to enhance coating adhesion. The carbide phase (WC) and the carbon (C) phase were deposited simultaneously by direct-current magnetron sputtering of a WC target and plasma-assisted chemical vapour deposition using hydrocarbon gas, respectively. The influence of the chromium interface layer thickness, the amount of WC phase and the flow of hydrocarbon gas on the mechanical and tribological properties of the coatings have been investigated. The coatings have been characterised with respect to their chemical composition (glow discharge optical emission spectroscopy), hardness (Vickers microhardness), morphology (scanning electron microscopy, SEM), roughness (profilometry), residual stress (beam bending), critical load (scratch testing) and abrasive wear resistance (the “dimple grinder test”). Furthermore, a ball-on-plate test was employed to obtain information about the frictional properties and sliding wear resistance of the coatings. The wear mechanisms and wear debris were analysed by SEM, Auger electron spectroscopy and electron spectroscopy for chemical analysis. All WC/C coatings displayed a thickness between 2 and 4 μm and a surface roughness in the range of 10 to 70 nm. The hardness varied between 1500 and 1800 HV. The coating residual stress was found to range from −2.5 to −0.5 GPa. The scratch test revealed a relatively high critical normal load, i.e., a relatively good adhesion of the WC/C coatings to the HSS. The abrasive wear resistance was found to be very high, in fact equally as high as that of PVD TiN. In the sliding wear test it could be seen that the coating containing the lowest amount of carbide phase (WC), i.e., the highest amount of carbon phase (C), and which had the highest compressive residual stress yielded the lowest friction and wear rate against steel. In addition, this coating was also found to yield the lowest wear rate of the counter material. In summary, a WC/C coating with overall good mechanical and tribological properties was obtained provided a relatively thin chromium layer was deposited first and if a relatively high acetylene gas flow was utilised during deposition of the WC/C layer.