碳纤维对增强的摩阻材料的摩擦磨损特性的影响

利用Ｄ－ＭＳ摩擦磨损试验机，用自制的碳纤维增强摩阻材料中碳纤维含量，表面状态，强度和长度对摩擦磨损性能的影响进行了试验研究。     

碳纤维对增强的摩阻材料的摩擦磨损特性的影响

利用Ｄ－ＭＳ摩擦磨损试验机，用自制的碳纤维增强摩阻材料中碳纤维含量、表面状态、强度和长度对摩擦磨损性能的影响进行了试验研究。     

三层复合轴承材料的试验研究

本文对研制的聚四氟乙烯和聚甲醛两种三层复合轴承材料进行摩擦磨损试验研究，并就轴承摩擦副表面结构对磨损性能的影响进行了试验分析，其结果可供实际应用时参考。     

三层复合轴承材料的试验研究

本文对研制的聚四氯乙烯和聚甲醛两种三层复合轴承材料进行摩擦磨损试验研究，并就轴承摩擦到表面结构对磨损性能的影响进行了试验分析，其结果可供实际应用时参考．     

氧化膜对半金属汽车刹车材料摩擦磨损性能的影响

以一种半金属汽车刹车材料为研究对象,分析了按不同比例配入铜纤维后材料摩擦表面氧化膜的生成及其对摩擦磨损性能的影响。结果表明,中温下半金属刹车材料的氧化对摩擦磨损性能起着较为重要的作用,中温下的氧化磨损为其主要的磨损机理,增加铜纤维的含量有利于减少低温下的粘着磨损和中温下的氧化磨损。     

硫化温度对纸基摩擦材料性能的影响

采用造纸工艺制备了一种湿式纸基摩擦材料,研究了硫化温度对材料耐热性、动摩擦因数、摩擦力矩、磨损率、磨损表面微观形貌的影响.研究结果表明:硫化温度高于或低于160℃时,材料的耐热性能减弱,树脂和竹纤维的热分解较为严重,热磨损主要影响着材料摩擦磨损性能的稳定;160℃时,材料的磨损较小,磨损表面平整致密,在循环制动中动摩擦系数波动性较小,摩擦力矩的变化较平稳,降低了制动的噪音.     

Si的质量分数对C/C-SiC摩擦材料摩擦磨损性能的影响

以PAN基碳纤维针刺整体毡为预制体,经化学气相渗透法制得C/C多孔坯体,采用反应熔体浸渗法制备了C/C-Si C摩擦材料。用XD-MSM型定速摩擦试验机测定摩擦磨损性能,研究了不同Si含量对C/C-Si C摩擦材料摩擦磨损性能的影响。利用VK-X200三维激光扫描显微镜观察了摩擦材料磨损后表面的微观形貌并探讨其磨损机制。结果表明:随着Si质量分数的增加,摩擦材料的硬度和冲击强度逐渐增大,开孔率逐渐降低,摩擦材料的磨损形式由单一的磨粒磨损转变为磨粒磨损和黏着磨损的混合磨损机制。3种摩擦材料中,Si质量分数为28.42%的C/C-Si C摩擦材料物理和力学性能均较好,摩擦系数较大,磨损率较小,摩擦磨损性能较好。 更多还原     

碳纤维/环氧树脂复合材料摩擦性能研究

采用液相氧化法合成氧化碳纤维,制备碳纤维/环氧树脂复合材料,研究了复合材料的力学性能和摩擦性能。结果表明,碳纤维经液相氧化后,复合材料的力学强度有所降低,但模量均有明显提高;碳纤维和氧化碳纤维能改善环氧树脂复合材料的摩擦性能,降低摩擦系数和减少磨损率,提高复合材料的耐磨性;复合材料的摩擦系数和磨损率均随着载荷和时间的增加而增大。由材料磨损表面的扫描电镜可知碳纤维/环氧树脂复合材料以磨粒磨损与粘着磨损为主,氧化碳纤维/环氧树脂复合材料以疲劳磨损和磨粒磨损为主。碳纤维和氧化碳纤维可以作为环氧基摩擦材料的增强材料,这一研究对于拓宽摩擦材料领域的研究发展具有重要意义和促进作用。     

半金属摩擦材料的摩擦磨损性能及磨屑形貌

采用D－MS定速式摩擦试验机，测定了3种金属纤维（钢纤维，黄铜纤维和紫铜纤维）增强的半金属摩擦材料与灰铸铁在不同温度下滑动摩擦的摩擦磨损性能，并收集磨屑，借助SEM扫描电子显微镜，观察，分析磨屑的形貌，研究材料磨损的内在机制。研究结果表明：紫铜纤维增强的磨擦材料与灰铸铁间的摩擦因数最稳定，磨损率最低；低温时，3种材料的磨屑均比较细小，在少数大颗粒的表面可以观察较深的划痕，有的带有明显的裂纹，说明该磨损主要由犁沟及微切削作用引起；高温时，磨屑多呈较大的块状或薄片状，这是粘结剂的高温分解和摩擦表面膜的热裂分解所致；对于铜纤维（黄铜或紫铜），在摩擦过程中还会发生铜在对偶表面的涂抹现象，这也是影响其摩擦磨损性能的一个重要因素。     

退火温度对7022铝合金干摩擦性能的影响

对7022铝合金的不同温度退火试样进行干滑动摩擦磨损试验,用扫描电镜、显微硬度测试仪和三维形貌仪分析各试样的磨损机制.结果表明,退火温度对材料的显微硬度和摩擦磨损性能有明显影响,退火温度在200℃时,材料显微硬度和摩擦磨损性能最好,此温度下材料得到完全再结晶,且晶粒细化;摩擦磨损性能随着显微硬度的提高而减小.塑变磨损、磨粒磨损和疲劳磨损为7022铝合金的主要磨损机理.     

Friction Stir Processing of Thixoformed AZ91D Magnesium Alloy and Fabrication of Surface Composite Reinforced by SiC_ps

The microstructural evolution characteristics of the thermomechanically affected zone (TMAZ) alloy during friction stir processing (FSP) of thixoformed (TF) AZ91D alloy were investigated. Simultaneously, a surface composite layer reinforced by SiC particles (SiCps) was prepared on the alloy by FSP and the corresponding tribological properties were examined. The experimental results indicate that dynamic recrystallization and mechanical separation (including splitting and fracture of the primary grains) are ...     

Analysis on tribological properties of potentially new friction material with response surface method

The tribological properties of newly developed friction material were evaluated by statistical analysis of the major affecting factors.The material for investigation was non-metallic friction material synergistically reinforced with aramid fibre and CaSO 4 whisker,which was developed for hoisting applications in coal mine.The response surface method(RSM)was employed to analyze the material performances affected by the independent and interactive effect of the factors under the normal working condition and severe working condition,respectively.Results showed that under the normal working condition,the newly developed material exhibited stable tribological properties which were insensitive to the test conditions.While under the severe working condition,the sliding velocity was the most dominant factor affecting the friction coefficient.Additionally,compared to the commercially available material,the modified material showed superior wear resistance and thermal stability.     

Friction stir processing of thixoformed AZ91D magnesium alloy and fabrication of surface composite reinforced by SiC<Subscript>p</Subscript>s

The microstructural evolution characteristics of the thermomechanically affected zone (TMAZ) alloy during friction stir processing (FSP) of thixoformed (TF) AZ91D alloy were investigated. Simultaneously, a surface composite layer reinforced by SiC particles (SiC_ps) was prepared on the alloy by FSP and the corresponding tribological properties were examined. The experimental results indicate that dynamic recrystallization and mechanical separation (including splitting and fracture of the primary grains) are the main mechanisms of grain refinement for the TMAZ. A composite surface reinforced by uniformly distributed SiC_ps was prepared on the alloy. Compared with the corresponding permanent mould casting alloy and the TF alloy without composite surface, the TF alloy with composite surface has the highest wear resistance and lowest friction coefficient.     

GF增强尼龙1010复合材料的磨擦学性能研究

制备了玻璃纤维（GF）增强尼龙1010复合材料,在环一块磨损试验机上研究了复合材料的摩擦学性能。结果表明：GF含量对复合材料的摩擦学性能有显著影响,GF质量分数为35％时增强效果较好;随着滑速的增加,GF增强尼龙1010复合材料的摩擦系数和磨损量持续上升。干摩擦下的复合材料磨损以疲劳断裂和粘着为主,且纤维出现磨损、断裂及从基体中剥落的现象。在油润滑下材料向对偶产生轻微的转移,与干摩擦相比复合材料的摩擦系数和磨损量大为降低;水润滑下的尼龙以化学腐蚀磨损和磨粒磨损为主,此时复合材料摩擦系数也有较大程度的降低,但磨损量较干摩擦增大。     

Effect of friction heat on tribological behavior of M2 steel against GCr15 steel in dry sliding systems

The tribological behavior depends significantly on friction heat under high sliding velocity. Many factors influence the conduction rate of friction heat, such as thermophysical properties of the pairs, the formation components of interface-film, environ- ment mediums, etc. Through theoretical and experimental studies on surface temperature, the heat partition approaches have been applied to the pairs of M2 steel against GCr15 steel to compare and discuss their tribological behavior in dry sliding contact. The re- sults indicate that the values of the contact pressure have little effect on the heat partition at a high sliding velocity of 40 m/s. Fur- thermore, the degree of correlation between the dynamic temperature and friction coefficient is obvious, and the correlation degree of parameters increases as the pressure grows. A close correlation exists among the temperatures measured from different points of the pin specimen. At last, X-ray diffraction analysis denotes that the carbides of secondary M6C are separated out during the process of friction.     

Tribological Properties of MoSi2 Against AISI10045 Steel Under Sliding Friction

MoSi2 samples were prepared by a self-propagating high-temperature synthesis （SHS） and a hot-press technique. The sliding friction and wear properties of intermetallic MoSi2 against AISI10045 steel under dry friction and oil lubrication conditions were investigated with a MRH-5A type ring-on-block friction and wear tester. The elemental composition, microstructure and worn surface morphology of the MoSi2 material were observed and analyzed by means of scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The synthetic parameter pv value reflecting friction work, was used to discuss the tribological properties of MoSi2 material. The results show that 1） oil lubrication can obviously improve the tribological properties of MoSi2, 2） the bigger the pv value, the greater the antifriction and the abrasive resistance of MoSi2 under oil lubrication, 3） with an increase in the pv value, the wear mechanism of MoSi2 material under dry sliding friction is the fatigue fracture and adhesive wear and 4） under oil lubrication the wear mechanism is mainly fatigue pitting.     

新型无石棉摩阻材料研究

以酚醛树脂、玻璃纤维、氧化铝、氧化硅、硫酸钡、铜粉及石墨待普原料按一定的配比制得了一种新型的摩阻材料并测试了摩擦磨损特性。实验结果表明,与石棉摩 阻材料相比,此种材料具有摩擦系数高,耐磨性好,抗热衰退性好的优点,而且对对偶的磨损也小,可以替代石棉摩阻材料。     

指尖密封用炭-炭复合材料摩擦磨损性能

为确定指尖密封用炭-炭(炭纤维增强炭基体)复合材料的摩擦学性能,针对指尖密封的轻载使用条件,应用UMT-2摩擦磨损测试仪进行炭-炭复合材料摩擦磨损性能试验,测量摩擦系数与磨损率,并采用扫描电子显微镜(SEM)分析材料的摩擦磨损机理.结果表明,无纬布层垂直于摩擦平面时,材料的摩擦系数和磨损率较低.载荷增加,较高密度材料的磨损率增加缓慢,摩擦系数减小.与载荷相比,材料磨损率受频率的影响较小,且随频率升高摩擦磨损性能越好.磨损表面的SEM分析表明:低频、低载条件下材料发生磨粒磨损;频率的提高加快磨屑膜的成形,自润滑能力增强;载荷的增加虽使磨屑快速被挤压形成磨屑膜,但磨屑膜被不断挤出剥落,纤维裸露断裂产生严重磨损,这一点在材料密度较低时表现更为显著.选用较高密度的材料以及布置无纬布层垂直于摩擦平面可以有效缓解密封材料的磨损.     

Effect of counterface materials on friction and wear behavior of double glow glasma discharge surface alloying on Ti22Al25Nb alloy

Samples of surface chromising layer were prepared by the double glow plasma discharge technique. X-ray diffraction and X-ray photoelectron spectroscopy(XPS) analysis of different elements confirmed the formation of chrome in the layer. Their tribological properties were investigated by pin-on-disk tribometer. Silicon nitride, GCr15, and nickel-based alloy were selected as counterface materials. Results indicated that the lowest friction coefficients and wear rate were obtained when substrate and chromising layer against nickel-based alloy, and tribological properties of chromising layer were better than those of substrate. The highest friction and wear rate were samples against silicon nitride alloys. In the case of three rubbing pairs, the unchangeable materials against different hardness counterfaces leaded to different wear mechanisms. Samples against silicon nitride exhibited abrasive mechanism, and when GCr15 and nickel-based alloy were used as counterface, transfer film and glaze layer formed on the contact surface, which played the main role in decreasing friction and wear. Funded by the Natural Science Foundation of Jiangsu Province China(No.BK2005128), and the Scientific Research Foundation of Nanjing University of Information and Technology