三维连续网状多孔陶瓷增强ZL102复合材料的摩擦磨损特性

对铸造铝基三维连续网状多孔陶瓷复合材料在干摩擦和油润滑条件下的耐磨性进行了较细致的分析,并对影响该复合材料滑动磨损行为的因素进行了讨论。结果表明：无论在干摩擦还是油润滑条件下,复合材料均比基体合金耐磨,尤其是高载时,复合材料的耐磨性能更突出地显示出来。     

网状陶瓷复合材料的滑动磨损行为

研究了三维连续网状多孔陶瓷复合材料在干摩擦条件下的滑动磨损行为。结果表明：复合材料的耐磨性优于基体合金;复合材料对磨环的磨损量大于基体合金对磨环的磨损量,但复合材料摩擦副的总磨损量比基体合金摩擦副的小。     

SiCp颗粒增强AZ80镁合金的摩擦磨损特性

本文研究了喷射搅拌铸造法制备的ＳｉＣｐ／ＡＺ８０复合材料的摩擦磨损性能。结果表明：复合材料的耐磨性优于基体合金；复合材料磨损表面存在由ＧＣｒ１５对磨环转移的富铁层，使复合材料－ＧＣｒ１５摩擦副的摩擦系数比ＡＺ８０－ＧＣｒ１５摩擦副低；复合材料的对磨环磨损量大于基体合金的对摩环磨损量，但复合材料摩擦副的总磨损量比基体合金摩擦副的小。     

网络陶瓷增强铝基复合材料的摩擦磨损性能及磨损模型研究

研究了网络陶瓷增强铝基复合材料在干滑动摩擦条件下的磨损行为,并在试验的基础上建立了复合材料的磨损模型.结果表明,复合材料的耐磨性明显优于基体合金,其主要原因是增强体独特的网络结构可制约基体合金的塑性变形,并减少偶件同基体合金的接触;从复合材料的磨损率方程中发现,在载荷、转速、时间3个影响因素中,转速对磨损率的影响最大,载荷次之,时间最小;磨损率方程的预测值与实测值符合的很好,建立的磨损模型符合实际磨损状况.     

ZL109铝合金及其复合材料干滑动磨损表面及亚表面的观察与分析

利用预制体挤压浸渗法分别制备了Al2O3或C短纤维单一增强以及两者混杂增强ZL109金属基复合材料，探讨了基体合金及其复合材料的干滑动摩擦磨损行为，并对其磨损表面及亚表面形貌进行了观察和分析。结果表明：C纤维在复合材料中起到一定的自润滑作用，Al2O3和C短纤维混杂增强复合材料的磨损率低于基体合金和单一纤维增强的复合材料。与基体相比，单一Al2O3增强复合材料从轻微磨损到急剧磨损的临界转变载荷明显提高，经C纤维混杂后，其临界载荷进一步提高。经磨损表面及亚表面的观察与分析表明：纤维增强对基体合金的磨损机制没有明显影响，在轻微磨损阶段，主要磨损机制为犁沟磨损和层离，亚表面分为3个区域：表层未脱落的剥离层、亚表面裂纹形成区以及未受影响区。发生严重磨损时，磨损机制转变为严重的粘着磨损，此时表层未脱落的剥离层遭到破坏。     

原位反应液相线铸造Al2O3/Al-Cu复合材料的组织及摩擦磨损特性研究

采用原位反应液相线铸造法制备了Al2O3/Al-Cu复合材料及基体合金Al-Cu,分析其铸态组织,测试不同条件下复合材料及基体合金的滑动磨损特性.结果表明,在同等条件下(转速或压力相同)复合材料的耐磨性优于基体材料.这说明增强相的加入显著提高了材料的耐磨性,复合材料比基体的耐磨性提高了1.5～4.0倍;且复合材料的磨损量随着载荷的增加而增大,随着转速的升高而减小,它在高速低载条件下表现出较好的摩擦磨损特性.     

网络陶瓷增强铝基复合材料的摩擦磨损性能

采用压铸技术成功制备了网络陶瓷(骨架)增强铝基复合材料,研究了其在干摩擦条件下的滑动摩擦磨损行为.结果表明,复合材料的耐磨性能远优于基体合金,主要是由于网络陶瓷(骨架)裸露在磨损表面,成为微凸体,起承载作用,抑制或延迟了基体从轻微磨损向严重磨损的转变.同时将载荷分散至各个方向,抑制了磨损面基体合金因塑性变形产生的流失.     

三维网络陶瓷增强铝基复合材料的干摩擦磨损性能

设计和制备了一种新型的三维网络陶瓷(骨架)增强铝合金复合材料.研究了铝合金及不同成分复合材料在不同温度及载荷下的摩擦系数和磨损率;用扫描电镜(SEM)观察其磨损表面,并分析了三维网络陶瓷(骨架)对铝合金磨损机制的影响.结果表明:复合材料的耐磨性远优于铝合金,而且随着三维网络陶瓷体积分数、温度及载荷的增加,复合材料的抗磨损性能明显提高;这种新型复合材料的摩擦系数随载荷变化保持稳定;在很宽的温度范围内,摩擦系数的稳定性均优于铝合金.这是由于三维网络陶瓷在磨损表面形成硬的微凸体起承载作用,其独特的结构制约了基体合金的塑性变形和高温软化,有利于磨损表面氧化膜的留存.     

双尺度Al_2O)3颗粒增强铝基复合材料的组织和性能

通过粉末冶金真空热压烧结法制备了双尺度(nm、μm)混杂Al2O3颗粒增强铝基复合材料,并对复合材料的组织、密度、硬度及耐磨性进行了研究。结果表明,双尺度复合材料中增强颗粒在基体中分布均匀,没有明显的团聚现象,微米颗粒含量超过20%时,复合材料的空隙增多;4%的30nm颗粒+15%的75μm颗粒的双尺度复合材料的性能最好,其硬度比基体Al-Si合金提高70%,耐磨性比基体铝硅合金提高7.22倍;双尺度混杂颗粒复合材料的耐磨性高于单一纳米或微米颗粒复合材料,其磨损机制主要为粘着磨损、犁削和磨粒磨损。     

纳米SiCp增强镁基复合材料的高温磨损性能

采用机械搅拌与高能超声处理相结合的分散方法制备了纳米SiCp增强的镁基复合材料,研究了基体及其复合材料从常温到300 ℃温度范围内的磨损性能.结果表明,基体和复合材料在试验温度范围内的磨损量都经历了从轻微磨损到严重磨损的转折点,复合材料的转折温度要比基体材料的高.轻微磨损阶段主要发生磨粒磨损和粘着磨损,当温度超过临界转变温度后,磨损机制转变成严重的粘着磨损和大片的剥层磨损,并伴随着严重的氧化磨损.     

Microstructure and wear characteristics of ATZ ceramic particle reinforced gray iron matrix surface composites

The alumina toughened zirconia(ATZ) ceramic particle reinforced gray iron matrix surface composite was successfully manufactured by pressureless infi ltration. The porous preform played a key role in the infi ltrating progress. The microstructure was observed by scanning electron microscopy(SEM); the phase constitutions was analyzed by X-ray diffraction(XRD); and the hardness and wear resistance of selected specimens were tested by hardness testing machine and abrasion testing machine, respectively. The addition of high carbon ferrochromium powders leads to the formation of white iron during solidifi cation. The wear volume loss rates of ATZ ceramic particle reinforced gray iron matrix surface composite decreases fi rst, and then tends to be stable. The wear resistance of the composite is 2.7 times higher than that of gray iron matrix. The reason is a combination of the surface hardness increase of gray iron matrix and ATZ ceramic particles and alloy carbides protecting effect on gray iron matrix.     

纳米Al2O3-40％TlO2复相陶瓷颗粒增强镍基合金复合涂层的摩擦学性能

运用等离子喷涂技术在7005铝合金表面制备Al2O3-40%TiO2纳米结构颗粒增强镍基合金复合涂层,分析其微观结构,研究其在不同载荷和速度条件下的摩擦磨损性能。结果表明：复合涂层主要由γ-Ni、α-Al2O3、γ-Al2O3和金红石型-TiO2等相组成,其摩擦因数和磨损失重较镍基合金涂层显著降低。在轻载3 N 时,复合涂层磨损表面的接触应力较低,主要发生微观切削磨损;当载荷上升至6~12 N时,接触应力高于磨损表面的弹性极限应力,复合涂层的磨损机理变为多次塑变磨损、微观脆性断裂磨损和磨粒磨损。随着速度的增大,磨损表面的接触温度逐渐升高,复合涂层以多次塑变磨损、疲劳磨损和粘着磨损为主。     

2024铝合金微弧氧化/TiC复合膜的制备及耐磨性能

在含有TiC微粒的硅酸盐体系电解液中对2024铝合金进行微弧氧化处理,制备含有TiC成分的复合陶瓷膜。利用SEM、EDS、XRD观察分析复合陶瓷膜的微观形貌、膜层中主要成分沿截面方向的分布及膜层的相结构,用纳米压痕硬度仪、激光共聚焦显微镜、摩擦磨损试验机测量复合陶瓷膜的硬度、表面粗糙度及摩擦系数。观察磨痕形貌,采用激光共聚焦显微镜测量磨痕体积,评估磨损率。结果表明:与不含TiC微粒的电解液中制备的微弧氧化膜相比,复合陶瓷膜的硬度更高、摩擦系数更小、磨损率更低,复合陶瓷膜的磨损率仅为微弧氧化膜的1/12,耐磨性更好。     

Evaluation of sliding wear behavior of graphite particle-containing magnesium alloy composites

1 Introduction More and more magnesium alloy products have been used in automobile and aerospace industries due to their low density, high specific strength and specific stiffness, good damping characteristic, excellent machineability and castability, etc…     

钎焊法制备硬质颗粒复合材料的耐磨性和磨损机理

为了提高硬质颗粒复合合金材料的耐磨性并揭示其与界面结合、微观组织及磨损机理之间的关系,本文设计并通过钎焊法,在普通铸钢件表面制得了厚度可达30mm的WC颗粒增强铜基合金覆层,测试分析了上述各种因素对此覆层耐磨性的影响.力学性能测试表明:该覆层与钢母体结合强固,且具有良好的综合性能.SEM观察和能谱分析说明:复合合金层组织由弥散强化铜基合金基体与WC颗粒相组成,且二者形成了强有力的反应性结合.磨料磨损试验证明:该复合合金在二体和三体磨损条件下均有较高的耐磨性,与低合金钢的切削和犁沟变形应变疲劳以及高铬铸铁的切削磨损机理不同,该复合合金与切削及脆性剥落两大磨损机理相对应.     

Wear response of a Zn-base alloy in the presence of SiC particle reinforcement: A comparative study with a copper-base alloy

An attempt has been made in this study to examine the effects produced by the reinforcement of (10 wt%) SiC particles on the sliding wear behavior of a Zn-base alloy. The matrix alloy was also subjected to identical test conditions to assess the influence of the SiC dispersoid phase. The wear characteristics of the (Zn-base alloy) composite and the matrix alloy were also compared with those of a Cu-base alloy (i.e., an aluminum bronze) in order to understand the scope of exploiting the Zn-base alloy matrix/composite as a substitute material for the latter (Cu-base) alloy. It has been observed that low frictional heat generated at the lower sliding speed (0.42 m/s) enabled the Zn-base (matrix) alloy to perform better than the composite material, while the Cu-base alloy showed intermediate wear resistance. On the contrary, the trend changed at a higher sliding speed (4.62 m/s) when high frictional heating caused the wear behavior of the Cu-base alloy to be superior to that of the Zn-base (matrix) alloy. The composite in this case performed better than the matrix alloy. The wear behavior of the specimens has been explained in terms of factors like microcracking tendency and thermal stability introduced by the SiC dispersoid phase and lubricating, load bearing, and low melting characteristics of microconstituents like α and η in the (Zn-base) alloy system and the thermal stability of the Cu-base alloy. It seems that the predominance of one set of parameters over the other actually controls the overall performance of a material. Once again, it is the test conditions that ultimately allow a particular set of factors to govern the other and influence the response of the specimens accordingly. The observed wear behavior of the samples has been substantiated further with their wear surface characteristics.     

Al2O3-TiO2对铝合金表面激光熔覆NiAl涂层组织性能的影响

目的 进一步提高6061铝合金表面的硬度、耐磨性。方法 应用脉冲Nd:YAG激光器在6061铝合金表面制备了NiAl合金涂层和NiAl/Al2O3-TiO2复合涂层。通过SEM、X射线衍射仪系统研究了Al2O3-TiO2陶瓷相添加对NiAl熔覆层组织形貌、成分分布、物相组成的影响。利用HVS-1000硬度测试仪及HSR-2M高速摩擦磨损机,对熔覆层硬度分布及耐磨性进行测试分析。结果 Al2O3-TiO2陶瓷颗粒加入使涂层宏观成形质量明显提高,表面平整光滑、波纹均匀,熔覆层枝晶间距减小,组织结构明显细化。与NiAl熔覆层相比,在NiAl/Al2O3-TiO2复合涂层中,具有较高硬度的Al3Ni、Al3Ni2硬质相含量增大。同时,高硬度Al2O3和良好韧性的TiO2、NiTi金属间化合物在复合涂层内部形成。NiAl/Al2O3-TiO2复合涂层的显微硬度平均可达650HV0.2,相比NiAl涂层提高了300HV0.2;磨损体积仅为铝合金基体的1/9,相比NiAl涂层降低了35%。干摩擦条件下,NiAl/Al2O3-TiO2复合涂层的犁削、剥落现象显著降低。结论 在细晶强化、硬质相弥散强化及良好韧性的NiTi金属间化合物共同作用下,6061铝合金表面硬度和耐磨性得到显著提高。     

High Temperature Sliding Wear of Spray-Formed Solid-Lubricated Aluminum Matrix Composites

The present work describes the tribological study of the aluminum metal matrix composite manufactured by the spray atomization and deposition technique. The immiscible element Sn is added in the Al-Si alloy in different proportion to see its effect on wear behavior. The economical mineral zircon sand (8 vol.%) of size range 63-90 μm has been used as ceramic reinforcement. The microstructural features showed that Sn and reinforced particles were homogeneously dispersed in the matrix phase. The wear experiments were conducted at high temperature on pin-on-disk wear testing machine. The wear debris and worn surfaces are analyzed with the help of scanning electron microscope equipped with energy-dispersive spectroscopy facility. The Al-Si-10Sn/ZrSiO₄ composite offers higher wear resistance as compared to base alloy and other composites irrespective of the high temperature conditions of wear tests.     

超疏水结构对AZ91D镁合金微摩擦磨损性能的影响

目的 研究微/纳米复合超疏水结构的摩擦磨损机制,提高镁合金微摩擦磨损性能。方法 首先采用激光刻蚀获得微米结构,然后表面涂覆SiO2纳米颗粒,获得微/纳米复合结构,最后涂覆低表面能物质获得超疏水表面。用接触角测量仪测量超疏水表面的静态接触角,使用微摩擦磨损实验机分析超疏水表面的摩擦磨损性能,使用扫描电子显微镜观察表面磨痕形貌。结果 当载荷为1 N时,超疏水表面的摩擦系数约为0.04,基体表面约为0.06。随着载荷的增加,超疏水表面的摩擦系数逐渐与基体相近,并逐渐超过基体。随着时间的增加,超疏水表面的摩擦系数呈增加趋势,由0.04逐渐增加到0.08,基体试样没有明显的上升趋势。相同条件下,超疏水表面的磨痕宽度大于基体表面,但磨痕宽度的增大趋势小于基体表面。结论 微/纳米复合结构超疏水表面的摩擦磨损过程不同于光滑基体。超疏水表面的磨损首先发生于微/纳米凸起结构,之后发生于被微/纳米凸起填平的微米凹坑区,然后发生于激光加工热影响区表面,最后发生于镁合金基体。在所受载荷低于1~3 N时,超疏水表面微凸起结构能延缓超疏水表面摩擦磨损的发生,改善耐磨性能。     

复合陶瓷挺柱的钎焊质量控制

复合陶瓷挺柱由于其优越的耐磨与减磨性能而成为取代现有金属合挺柱的最佳材料，尤其是在使用条件苛刻的发动机中，钎焊质量是影响复合陶瓷挺柱使用性能的关键因素之一，因此如何保证与控制钎焊质量是复合陶瓷挺柱进入实际应用的前提。而影响插柱而使用性能并与钎焊相关的是钎经和钎焊引起的变形。本文从控制复合陶瓷挺柱的钎焊质量出发，试验研究了影响钎焊着率和焊后变形的各种因素和规律，得到了有实际意义的结论。