等离子喷涂硫化亚铁润滑层的摩擦学性能

利用等离子喷涂在 45钢表面制备了三种厚度不同的硫化亚铁固体润滑层。在QP 1 0 0摩擦磨损试验机上测定了硫化亚铁喷涂层在油润滑条件下的摩擦学性能。利用XRD分析了硫化亚铁喷涂层的相结构 ,用SEM观察了喷涂层的磨面形貌。结果表明 ,硫化亚铁喷涂层的减摩、耐磨、抗擦伤性能明显优于 45钢原始表面。     

Investigation on anti-wear properties of sulfide layer on bearing steel lubricated by oil-containing FeS particles

To enhance the anti-wear properties of the sulfide layer on the surface of 52100 steel under harsh conditions, FeS particles were mixed into the oil as additive. The anti-wear properties of plain surface and sulfurized surface under base oil and oil-containing FeS particles lubrication were investigated by a ball-on-disk tester. The composite effects of sulfide layer and FeS particles with different sizes and amounts in base oil were studied as well. The results showed that the anti-wear properties can be improved for sulfurized and plain steel surfaces after FeS particles were used as additive in oil. The composite effect of sulfide layer and FeS particles possessed very good anti-scuffing and anti-wear properties. The FeS particle could supplement the loss of sulfur from the sulfide layer in the wear process, so that the service life of FeS film can be prolonged under more harsh conditions. An appropriate addition amount of FeS is important for the composite effect.     

等离子喷涂纳米SiCp/FeS复合涂层的摩擦学性能

用等离子喷涂法成功制备了SiCp/FeS复合涂层,SiC颗粒尺寸为纳米级,均匀分布于FeS基体,涂层和40Cr钢基体结合良好.研究了FeS涂层和SiCp/FeS复合涂层的摩擦学性能.结果表明,SiCp/FeS复合涂层兼具优良的减摩性能和耐磨性能.在干摩擦条件下,掺入质量分数为0.2和0.3的纳米SiC颗粒时,摩擦系数和FeS涂层接近,但表面磨损体积显著降低,降幅可达1个数量级;油润滑条件下,SiCp/FeS复合涂层的摩擦系数低于FeS涂层,复合涂层具有比FeS涂层更佳的减摩性能.     

Wear behavior of high velocity arc sprayed 3Cr13 steel coating in oil containing sand

To improve the wear resistance of the machine components serving in desert areas, the 3Cr13 stainless steel coating was produced by the high velocity arc spraying technique. The microstructure and phase constitute of the coating were analyzed by SEM and XRD. The effects of sand content on the friction and wear behaviors of the coating under the lubrication of oil containing sand were investigated on a ball-on-disk tester. SEM was used to reveal the wear mechanisms of the coating. The results show that the wear volume increases with increasing the sand content in the oil, and the sprayed coating exhibits better triobological properties compared with the 1045 steel. The predominant wear mechanisms of the sprayed coating are micro-cutting, brittle fracture and delamination.     

离子渗硫层的抗擦伤性能及耐磨性研究

采用低温离子渗硫技术在45钢表面形成一定厚度的渗硫层.用销盘试验机在机械油润滑条件下对渗硫表面的抗擦伤性能,减摩及耐磨性能进行了系统研究.采用EDX和AES分析了边界润滑膜的成分.结果表明在低速条件下渗硫层可显著改善钢表面的扰擦伤性能,且具有较好的减摩耐磨作用.在磨损过程中,渗硫层促进了摩擦表面氧化物的形成.厚度适当的渗层可使边界润滑膜中的硫氧比处于最优范围,使表面承载能力提高.同时其对磨面的磨损也有所降低.     

铁基含油轴承材料表面硫化改性及摩擦学性能

为改善边界润滑工况下铁基含油轴承材料的摩擦学性能,采用低温液体渗硫技术在材料表面形成一层固体渗硫层,微观检测渗硫层形貌与成分,并在端面摩擦磨损试验机上进行摩擦学实验,分析其摩擦磨损性能与自润滑机理。结果表明:渗硫层中固体润滑剂的主要成分为FeS,硫化物沿着基体孔道由材料表面向内部扩散,渗硫层的厚度约为15μm;与未硫化材料相比,硫化材料的摩擦因数明显降低,且硫化时间越长,轴承表面渗硫层的减摩性能越好;表面硫化改性后,利用轴承基体多孔含油与表面渗硫层的液固协同润滑作用,其综合摩擦磨损性能比单纯固体润滑或单纯油润滑的减摩性能都要好,边界润滑工况下的抗擦伤、抗咬合性能得到改善。     

Tribology properties of composite layer of CrMoCu alloy cast iron by combined treatment of ion nitrocarburizing and sulphurizing

Composite layer with nitrocarbonide and sulfide was made on the surface of CrMoCu alloy cast iron by combined treatment of ion nitrocarburizing and sulphurizing. The composite layer is composed of sulfide layer, nitrocarbonide hypo-surface layer and its diffusing layer, the size of sulfide globular grains distributing equably on the surface is in nano-micron-scale, and the phase structure of the composite layer is composed of FeS, FeS1-x, Fe2C and Fe3N. Under oil lubrication, sulphurized surface shows good scuffing-resistance only under low velocity, and nitrocarburized and sulphurized surface greatly improves the scuffing-resistance and wear-resistance of CrMoCu alloy cast iron, its integrated friction and wear properties are better than those of the plain and sulphurized surfaces under all the velocities.     

Tribological behavior of magnetron sputtering CrMoN/MoS2 composite coatings

CrMoN composite coatings were deposited on the surface of the stainless steel by magnetron sputtering,then were treated by low temperature ion sulfuration.FESEM equipped with EDX was adopted to analyze the morphologies and compositions of the surface,cross-section and worn scar of the sulfuration layer.The valence states of the film surface were detected by XPS.The nano-hardness and nano-modulus of the layer were measured by a nano tester.The results of the friction and wear show that the CrMoN/MoS2 composite coating is a kind of ideal solid lubrication layer and possess an excellent antifriction and wear-resistance.     

Structure and friction-reducing property of the sulfide layer produced by ion sulfuration

Sulfide layers with a certain thickness were made on the surface of 1045 and 52100 steels by means of the low-temperature ion sulfuration technique. Metallography, scanning electron microscope (SEM) + energy-dispersive x-ray analysis (EDX), and x-ray diffraction (XRD) were adopted to analyze the structure of sulfide layers; the tribological properties of the layers lubricated by paraffin oil were also investigated on a reciprocating tester. The results showed that sulfide layer is porous, and its structure is mainly composed of FeS, FeS₂, and substrate phases. The sulfide layer possessed a remarkable friction-reducing effect; its friction coefficient was lower on average, by about 50%, than that of the surface without layer. With the increase of layer thickness, its friction coefficient was unchanged, and under low load conditions, its operational period was prolonged. Under the same experimental conditions, the operational period of sulfide layer on 52100 steel was longer than that on 1045 steel, and its friction coefficient was lower as well.     

石墨增强聚酰亚胺在海水中的摩擦学性能

目的为石墨增强聚酰亚胺复合材料在海水环境下的摩擦学应用提供实验依据。方法利用SST-ST销/盘摩擦试验机,研究了质量分数为15%石墨增强聚酰亚胺复合材料与17-4PH不锈钢组成的摩擦副在海水介质中的摩擦学性能,并与干摩擦和纯水润滑条件下的摩擦学性能进行比较。结果聚酰亚胺复合材料在干摩擦下的摩擦系数和磨损体积最大,分别为0.134、1.930 mm~3。干摩擦条件下,聚酰亚胺复合材料的磨损表面存在较深的犁沟,在犁沟周围出现了材料塑性流动及粘着剥落现象,对偶件表面有聚酰亚胺复合材料转移。磨损机理主要表现为磨粒磨损、材料塑性变形以及粘着和剥落。在纯水润滑下,聚酰亚胺复合材料表面存在较多材料粘着撕裂现象,同时存在宽浅不一的犁沟,磨损机理主要为粘着磨损和磨粒磨损。在海水润滑下,复合材料的摩擦系数和磨损体积最小,分别为0.086、1.235 mm~3,材料磨损表面十分光滑,只有沿运动方向存在少量轻微犁沟,磨损机理主要表现为磨粒磨损。结论石墨增强聚酰亚胺复合材料在海水中的摩擦学性能优于干摩擦和纯水环境下的摩擦学性能。     

H13钢QPQ处理工艺及耐磨性

目的研究540℃氮化温度下,QPQ处理对H13钢耐磨性的影响并选出最优氮化时间。方法通过SEM、EDS、XRD分别测试了H13钢QPQ处理后渗层微观组织形貌、成分分布以及物相组成。采用HVS-1000显微硬度计、MFFT-R4000高速往复摩擦磨损试验,分别对H13钢基体与540℃下不同氮化时间QPQ处理试样的渗层厚度、硬度分布、耐磨性进行了分析研究。结果 QPQ处理后,H13钢由表面向心部依次形成均匀致密的Fe_3O_4氧化膜、高硬度的ε-Fe_3N和CrN化合物层、α-Fe和Cr_2N稳定扩散层。N原子均匀分布于渗层内部。显微硬度沿截面均呈良好梯度分布。在540℃×4 h氮化工艺下,渗层次表层硬度达到最大值(1173HV0.1),是基体(498HV0.1)的2.4倍左右,磨损量仅为基体的1/13。H13钢磨损表面存在严重犁沟效应与大量磨屑,表现为典型的磨粒磨损伴随少量粘着磨损。而QPQ处理试样磨损表面仅存在少量浅显划痕,并伴随轻微结疤状凹坑,为粘着磨损。结论经QPQ处理,H13钢的耐磨性得到了显著提高,其中氮化工艺为540℃×4 h时所得的性能最优。     

低温离子渗硫层的干摩擦学性能对比研究

采用低温离子渗硫工艺，分别在W6Mo5Cr4V2,5CrNiMo,2Cr13及45钢表面制备FeS固体润滑层。研究干摩擦条件下的摩擦员性能和渗硫层截面与磨痕形貌，结果表明，4种钢渗硫后减磨耐磨性能都明显提高，其中渗硫W6Mo5Cr4V2钢的摩擦学性能最好，渗硫5CrNiMo钢、渗硫45钢及渗硫2Cr13钢的摩擦学性能依次降低，基体硬度及组织结构不同是渗硫层摩擦学性能产生差异的主要原因。     

DLC表面处理对高速钢耐磨性能的影响

经DLC表面处理的金属零件,其耐磨性会明显提高,因此DLC表面处理工艺在机械工业受到高度重视.以模具钢为对偶件,利用MM200磨损试验机比较了未经及经过DLC表面处理的高速钢在不同条件下摩擦磨损性能的差异,采用失重法评估耐磨性.试验结果表明:在高速和低速摩擦磨损试验条件下,无论在油润滑状态还是在干摩擦状态,经DLC表面处理后高速钢的耐磨性能都有明显的提高.同时还利用扫描电子显微镜(SEM)观察了磨痕微观形貌,并分析了磨损机理.     

感应加热金刚石/镍基复合涂层微观组织与性能

采用感应加热的方式,在65Mn钢基体表面制备了金刚石质量分数为10%的复合镍基涂层,利用SEM、EPMA、XRD对钎涂接头的微观组织和相组成进行了分析,研究了感应钎涂中金刚石/钎料界面的元素扩散机制和形成机制。并利用干砂橡胶轮磨损试验机测试了涂层的耐磨性能,分析了金刚石/镍基涂层的耐磨增强机制。结果表明,钎涂层中钎料合金物相主要为Ni₄B₃、(Ni,Fe)固溶体、Ni₃Si₂、CrB;金刚石与钎料合金发生了冶金反应,金刚石/钎料合金界面的C元素分布促使金刚石表面出现了双层碳化物结构,分别为金刚石侧的Cr₃C₂和在Cr₃C₂表面生长的Cr₇C₃。金刚石复合涂层的耐磨性能显著优于钢基体,涂层60min磨损失重仅0.25g,为钢对比试样磨损失重的1/12,金刚石在磨损过程中起到了阻挡犁沟扩展的作用,涂层的失效机制为镍基合金磨损和金刚石的脱落。     

高速电弧喷涂3Cr13钢涂层的组织及在含细沙油润滑条件下的磨损性能

为了解决含沙油润滑条件下材料的磨损问题,采用高速电弧喷涂技术制备了3Cr13钢涂层,使用SEM、XRD及MM200摩擦磨损试验机测试了涂层的组织结构及在含细沙油润滑条件下的磨损性能.结果发现,高速电弧喷涂3Cr13钢涂层组织致密,孔隙率<2%,结合强度>40 MPa,在含细沙油润滑条件下的耐磨性比38CrSi钢提高1.3～1.8倍,高速电弧喷涂3Cr13钢涂层的失效以磨粒磨损和扁平粒子的剥离为主.     

Dry friction and wear performance of SiC 3D continuous ceramic frame reinforced 7075A1 alloy

The dry friction and wear behavior of 7075 Al alloy reinforced with SiC 3D continuous ceramic network against Cr12 steel was studied with oscillating dry friction and wear tester under the testing conditions of 70 °C, 30 min, and the load range of 40–100 N. The experimental result shows that the characteristic of abrasive wear and oxidation wear mechanisms are present for 3D continuous SiC/7075 Al composite. 3D continuous network ceramic as the reinforcement can avoid composite from the third body wear that usually occurs in traditional particle reinforced composite. Under low load, the composite with low volume fraction of ceramic reinforcement exhibits better wear resistance due to the homogeneous reinforcement distribution with small pore size; on the contrary, under high load, the composite with high reinforcement volume fraction exhibits better wear resistance because of the coarse frame size. Hard SiC frame leads to the wear of Cr12 steel mainly. The frame with high volume fraction corresponds to the high Fe content.     

FeS固体润滑涂层的结构分析及磨损行为比较

新型固体润滑剂FeS涂层的优异减摩耐磨性能与制备工艺密切相关，利用低温离子渗硫和高速火焰喷涂的方法制备了FeS固体润滑涂层。在MM-200和QP-100磨损实验机上对比研究了这两种涂层的摩擦磨损行为。利用XRD分析了涂层的相结构，用SEM观察了涂层的表面、截面及磨面形貌，用划痕仪测定了涂层与基体的结合力。结果表明，离子渗硫FeS涂层的减摩性和耐磨性更好，而热喷涂层的抗擦伤性更佳，这是两种FeS涂层的组织结构不同所致。     

Effects of solid lubricants on friction and wear behaviors of the phenolic coating under different friction conditions

The phenolic coating filled with micro-MoS₂ or micro-graphite was prepared by spraying the coating precursors. The friction and wear behaviors of the unfilled and filled phenolic composite coating sliding against the steel ring were evaluated on an MHK-500 friction and wear tester under dry friction and under water lubrication conditions. The worn surfaces of the unfilled and filled phenolic coating and the transfer films formed on the surface of the steel ring were investigated using a scanning electron microscope (SEM) and an optical microscope (OM), respectively. FTIR analysis was performed to detect the chemical changes of the composite coating under different lubrication conditions. It was found that addition of graphite was effective in enhancing the wear life of the phenolic coating. Especially, the anti-wear ability of the phenolic coating was best when the content of graphite is 10 wt.%. However, the MoS₂ as filler was harmful to the friction and wear behaviors of the phenolic coating. The character of the fillers varied with the types of the solid lubricants and the transfer films of varied features formed on the counterpart steel ring, largely accounted for the different friction and wear behaviors of the unfilled and filled phenolic composite coating. Compared with under dry sliding, the phenolic composite coating filled with 10 wt.% MoS₂ or 10 wt.% graphite had lower friction coefficients and lower wear life under water lubrication. Since water hindered the formation of transferred films, and might penetrate and corrode the filler-matrix interface, the anti-wear ability of the phenolic composite coating reinforced with MoS₂ or graphite deteriorated under water lubrication.     

Wear and transfer characteristics of carbon fiber reinforced polymer composites under water lubrication

The tribological characteristics of carbon fiber reinforced polymer composites under distilled-water-lubricated-sliding and dry-sliding against stainless steel were comparatively investigated. Scanning electron microscopy (SEM) was utilized to examine composite microstructures and modes of failure. The typical chemical states of elements of the transfer film on the stainless steel were examined with X-ray photoelectron spectroscopy (XPS). Wear testing and SEM analysis show that all the composites hold the lowered friction coefficient and show much better wear resistance under water lubricated sliding against stainless steel than those under dry sliding. The wear of composites is characterized by plastic deformation, scuffing, micro cracking, and spalling under both dry-sliding and water lubricated conditions. Plastic deformation, scuffing, micro cracking, and spalling, however, are significantly abated under water-lubricated condition. XPS analysis conforms that none of the materials produces transfer films on the stainless steel counterface with the type familiar from dry sliding, and the transfer of composites onto the counterpart ring surface is significantly hindered while the oxidation of the stainless steel is speeded under water lubrication. The composites hinder transfer onto the steel surface and the boundary lubricating action of water accounts for the much smaller wear rate under water lubrication compared with that under dry sliding. The easier transfer of the composite onto the counterpart steel surface accounts for the larger wear rate of the polymer composite under dry sliding.     

硼对等离子熔覆高硼铁基合金组织和性能的影响

采用等离子弧熔覆技术在20g钢表面堆焊Fe-Cr-B-C系的铁基复合材料,利用X射线衍射（XRD）,光学显微镜（OM）,扫描电镜（SEM）,洛氏硬度计及湿砂磨损试验机等试验设备进行检测、试验,研究不同硼加入量对熔覆层显微组织与性能的影响规律.结果表明,熔覆层显微组织由过饱和α-Fe枝晶固溶体、枝晶间硼化物共晶组织以及碳化物等组成;熔覆层中硬质相主要有Cr2B,CrB2,Fe2B,Cr7C3,B4C等;随着硼含量的增加,硼化物明显增多,当硼添加量为5%时熔覆层的硬度及耐磨性达到最佳,其硬度值为66.1 HRC,磨损量仅为0.383 g;继续增加硼的添加量,熔覆层的耐磨性能降低.