浸银石墨电刷的显微组织结构与摩擦磨损的研究

通过扫描电子显微镜观察了浸银石墨电刷的显微组织结构和经过磨损实验后的表面形貌结构，分析了显微组织对电刷的导电性能和摩擦磨损性能的影响。并从磨擦学的角度，分析了电刷在集电环上滑动接触时各种摩擦要素的相互作用，探讨了浸银赭民刷的磨损机理。     

填料对聚合物基复合材料摩擦学行为的影响

本文综述了用于聚合物填充增强改性的填料种类、对摩擦学性能的影响以及填料的作用机理 ,同时讨论了填料的表面改性以及填料的选择标准。提出了今后研究填料对聚合物改性研究应注意的问题 ,从而对研究、开发、应用性能优异的聚合物基复合材料具有指导意义     

白口铸铁的磨料磨损行为及耐磨性

通过白口铸铁的耐磨试验，观察分析材料的磨面和磨屑；研究不同性能的白口铸铁在磨料磨损时的行为机理．     

Effect of artificial tribological layer on sliding wear behavior of H13 steel

An artificial tribological layer was formed on the worn surface during sliding, through supplying MoS2 , Fe2 O 3 or their equiponderant mixtures onto the sliding interface of H13/GCr15 steels.The effect of this tribological layer on the wear behavior of H13 steel was studied.The worn surfaces and subsurfaces of H13 steel were thoroughly characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS); the wear mechanisms were explored.The research results demonstrated that tribological layer did not exist during sliding of H13 steel with no additive, but it formed with the addition of MoS2 , Fe2 O 3 or their equiponderant mix-tures.When there was no tribological layer, the wear rate rapidly increased with an increase of the load.In this case, adhesive and abrasive wear prevailed.As the additives were supplied, the artificial tribological layer was observed to be immediately formed and stably existed on worn surfaces.This tribological layer presented an obvious protective function from wear and friction.Hence, the wear rate and friction coefficient were significantly decreased.MoS2 as tribological layer seemed to present more obvious protective function than Fe2 O 3 .By supplying their mixture, the artificial tribological layer possessed not only the load-carrying capacity of Fe2 O 3 , but also the lubricative capacity of MoS2 .These two simultaneous capacities could improve the friction and wear properties of H13 steel further.     

铬基钨镍钼高耐磨合金耐磨机理及产业化

本文研究了铬基钨镍钼高耐磨合金的耐磨机理。重点分析了铬基钨镍钼高耐磨合金的铸造工艺流程、铸造用废砂回收再生树脂砂的利用技术以及基于铬基钨镍钼高耐磨合金的耐磨产品。结果表明:铬基钨镍钼高耐磨合金的各种成分在不同工况中具有良好的耐磨性能。     

Cutting performance and wear mechanism of Sialon ceramic tools in high speed face milling GH4099

This work aims to reveal the cutting performance and wear mechanisms of Sialon ceramic tools for the high-speed face-milling of GH4099, with the goal of improving this process as well as designing more advanced ceramic cutting tools in the future. At the outset of this study, several single-factor experiments were designed with speed as a variable to gather various data on such tools. Failure patterns and tool life curves were first obtained through cutting tests. Afterwards, the tools were split at their place of wear (middle of notch and 1/2 depth of cut) to prepare for further analysis. Wear morphology and element composition distribution in the depth direction of the corresponding interface were then analyzed using a field emission scanning electron microscope (FE-SEM) and energy dispersive spectrometer (EDS) to explore potential diffusion and/or chemical wear. Finally, studies were conducted into the tools’ chemical wear under specific cutting conditions, finishing with a theoretical verification based on the thermodynamic principle of chemical reactions. This research discovered that notch wear was the main failure pattern for the high-speed face-milling of GH4099 under the suitable cutting conditions. Overall, the optimal cutting speed was 1000 m/min, with a tool life of about 3 min. Compared with cemented carbide tools, the machining efficiency for Sialon ceramic tools increased by over a factor of 16. The wear mechanisms for such tools demonstrated a mixture effect of abrasive, adhesive, diffusive and chemical wear. Diffusive wear mainly occurred in their flank faces, but did not constitute the main mechanism of notch wear; chemical wear proved to be a key reason for notch wear at higher temperatures. Based on the aforementioned research, this paper concludes with a proposed comprehensive model for notch wear.     

Wear mechanisms and effects of monolithic Sialon ceramic tools in side milling of superalloy FGH96

FGH96 is one kind of nickel-based superalloy, being widely used in aero engine hot end components due to its superior mechanical properties, while its machinability has been a challenge because of rapid tool wear and low machining efficiency. Recently, ceramic tools have gained widespread attention for their superior performance maintained at high temperatures. This work aims to study the wear mechanisms and the wear effects of monolithic Sialon ceramic tool in the side milling of superalloy FGH96. The specific influences of average flank wear on the side milling forces, machining temperatures, surface quality and micro-hardness of subsurface and the wear modes in the early and serious stage are analyzed. The results indicate that the milling temperatures, machined surface roughness and the depth of hardening layer will increase as the wear increases. While parallel to the cutting direction, the machined surface roughness is about 1.8 μm without significant changes until entering the serious wear stage. The milling force tends to undergo a decrease when the VB is about 0.22 mm, since the temperature is close to the solute temperature of γ’ phase in this stage. The main wear modes of monolithic ceramic tools are adhesive wear and flanking in the flank surface.     

Compomer的摩擦磨损特性

采用Compoglass，F2000，Elan，Dyract AP4种牙科用复合体材料(Compomer)，对其玻璃颗粒含量和表面硬度进行了测量，并在球一盘往复摩擦磨损试验机上考察了它们的摩擦磨损特性。结果表明：F2000的摩擦系数最高，Elan的摩擦系数次之，Compoglass和DyractAP的摩擦系数分别为第三和第四．摩擦系数随玻璃颗粒含量的增加而增加．在同样试验条件下，低摩擦系数的DyractAP和Compoglass与高摩擦系数的F2000和Elan相比具有较好的耐磨性．磨损机理主要表现为由玻璃颗粒脆性断裂引起的玻璃颗粒脱落和磨粒磨损。     

Erosive Wear and Wear Mechanism of in situ TiC_P/Fe Composites

1.IntroductionMetal-based composite is a kind of environmental ma-terial that can be reused.It combines the beneficialproperties of the metal matrix,such as ductility,goodthermal and electrical conductivity and high toughness,with those of the reforcement phase[1~3].The latter isusually a ceramic,serving to increase the elastic modu-lus,shear strength and hot strength,fatigue and wearresistance.Its development has been widely studied[4~8].Wear of metal materials causes a tremendous loss of ec…