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磨粒粒度分布对三体磨粒磨损的影响 总被引:2,自引:0,他引:2
实验研究了磨粒粒度分布、摩擦副表面粗糙度及摩擦面间距离对三体磨粒磨损的影响。结果表明,存在一最佳磨粒粒径分布均方差与摩擦副综合表面粗糙度之比使摩擦副的磨损最小;摩擦面间距离h对磨损的影响有一临界值h_c,当h大于h_c时,磨损随h的增大而减少,当h小于h_c时,磨损随h的减小而减少。对于综合表面粗糙底较大的摩擦副,当h小于某一值h_c以后,磨损将随着h的减小而增多。 相似文献
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为探讨AISI 1045钢的切削、磨削加工过程中材料的磨损机制随加工参数的变化规律,采用CFT-1型多功能材料表面综合性能测试仪对AISI 1045钢进行干摩擦磨损实验,研究干摩擦条件下不同摩擦速度、不同载荷对AISI1045钢磨损行为的影响,并用扫描电子显微镜(SEM)及能谱仪(EDS)对磨痕表面进行分析。结果表明:随着摩擦速度增大,AISI 1045钢的摩擦因数显著减小,磨痕深度先增加后减少,磨损机制由黏着磨损、磨粒磨损与轻微氧化磨损共同作用转变为氧化磨损、磨粒磨损和局部疲劳剥落;随着载荷增大,摩擦因数均值变化不大,磨痕深度依次增加,磨损机制由轻微黏着磨损和磨粒磨损转变为黏着磨损、磨粒磨损和轻微氧化磨损的共同作用。 相似文献
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为提高基于磨粒的机器状态监测的准确性,研究了磨粒特征随滑动磨损进程的变化规律.在球一盘磨损试验机上模拟可靠润滑和润滑不足2种工况下的摩擦磨损试验,分析了磨损过程中不同磨损阶段的磨粒尺寸分布和磨粒表面粗糙度,探讨了磨损进程中磨粒尺寸分布与磨粒表面粗糙度之间的关系.研究结果表明磨损进程中的磨粒特征的变化对机器状态监测极为有效. 相似文献
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基于一步法思路,采用金属3D打印机基于激光选区熔化(SLM)技术制备表面带有凹坑织构的TC4钛合金试样,采用光学相机、超景深显微镜和扫描电镜观察织构成形情况,利用激光共聚焦位移测试仪和显微维氏硬度计分别测试表面粗糙度和表面硬度,在干摩擦条件下采用摩擦磨损试验仪考察不同载荷下织构密度对TC4钛合金试样摩擦学性能的影响,并使用扫描电镜对摩擦实验前后的表面形貌进行分析。研究结果表明:一步法SLM成形能够在TC4钛合金表面获得成形良好的直径500 μm的织构;随着织构密度的提高,钛合金试样表面粗糙度增大,表面硬度有所降低;干摩擦条件下,提高TC4钛合金试样织构密度有利于磨屑的收集从而减少试样的三体磨损,提高载荷有利于改善摩擦副接触状态;5 N载荷下40%织构密度试样的平均摩擦因数和磨痕宽度均最小,与无织构试样相比,平均摩擦因数和磨痕宽度分别降低12%和16%;40%织构密度下,载荷提高会引起摩擦因数的降低和磨损量增大,磨损表面犁沟和片状剥落增多。在干摩擦条件下,3D打印一步法制备的表面织构可以显著改善TC4钛合金的磨粒磨损和黏着磨损。 相似文献
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食品机械加工中的摩擦磨损直接影响着食品安全问题。选用黄豆与316L不锈钢进行配副,采用滑动摩擦磨损试验机,研究干摩擦和水润滑条件对其摩擦学性能的影响。利用光学显微镜、光学三维形貌仪和红外光谱仪对试样的表面形貌、粗糙度和磨损表面成分进行了分析。结果表明:干摩擦条件下,黄豆/316L不锈钢摩擦副的平均摩擦因数波动较小,约为0.24,水润滑条件下其平均摩擦因数达到干摩擦条件下的4.4倍左右,且在摩擦过程中存在反复波动;与干摩擦相比,水润滑条件下不锈钢试样表面的磨痕宽度提高约10%,而黄豆试样表面的磨痕宽度的增加幅度约高达160%;水润滑摩擦过程中不锈钢磨痕表面产生更多黄豆分解的有机物,其磨痕表面的犁沟数量和深度均显著减少,黄豆试样磨痕表面基本没有犁沟;干摩擦条件下黄豆/不锈钢的磨损机制以磨粒磨损为主,而水润滑条件下,黏着磨损显著增加。 相似文献
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Assuming that micro-asperities and transferred particles on semicylindrical harder asperities with spherical ends ploughed a softer surface and that transferred particles at the front of harder asperities supported normal load, the effects on the wear rate of the parameters of surface topography, such as the mean height of micro-asperities, the radii of curvature at the tips of semicylindrical asperities and the length of an asperity, were analysed. The theoretical trends agreed well with the experimental wear rate trends for the polymers rubbed on harder surfaces with various roughnesses and those for various metals rubbed on the virgin surfaces of abrasive papers. The theoretical results showed that the wear rate decreased with a decrease in mean height of the micro-asperities and with increases in the radii of curvature at the tips of semicylindrical asperities and in the lengths of asperities. Furthermore, it was found, under the condition of abrasive wear, that the decrease in wear rate resulted from wear debris adhering to the front faces of the abrasive grains. 相似文献
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G.B. Stachowiak 《Wear》2004,256(6):600-607
Three-body abrasive wear resistance of mild steel and 27%Cr white cast iron was investigated using a ball-cratering test. Glass beads, silica sand, quartz and alumina abrasive particles with sizes larger than 200 μm were used to make slurries. It was found that the wear rates of mild steel increased with sliding time for all abrasive particles tested, while the wear rates of 27%Cr white cast iron were almost constant with sliding time. This increase in the wear rates of mild steel was mainly due to the gradual increase in ball surface roughness with testing time. Abrasive particles with higher angularity caused higher ball surface roughness. Soft mild steel was more affected by this ball surface roughness changes than the hard white cast iron. Generally, three-body rolling wear dominated. The contribution of two-body grooving wear increased when the ball roughness was significant. The morphological features of the wear scars depended on the shape of the abrasive particles and also on the hardness and microstructure of the wear material. Angular particles generated rough surfaces similar to those usually observed in high angle erosion tests. Rounded particles generated smoother surfaces with the middle area of the wear craters having similar morphology to those observed in low angle erosion. 相似文献
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钢质齿轮副在微纳米混合磨合油中的磨合试验研究 总被引:1,自引:1,他引:1
将微米和纳米固体粉末单独或混合加入到68#机械油中,配制了5种微米、纳米或微纳米混合磨合油,并试验研究了5种磨合油分别应用于钢质粗糙软齿轮副间的磨合磨损行为和作用机制。研究结果表明:当混合磨合油中微米颗粒粒度比齿面三维粗糙度Sa值小时,磨粒磨损并不显著,且纳米微粒起到加剧磨合磨损的作用。当混合磨合油中微米颗粒粒度比齿面三维粗糙度Sa值大时,磨粒磨损显著,但纳米微粒起到缓和磨合磨损的作用。齿面三维形貌表明纳米颗粒对齿轮副表面有填充作用,对磨合后齿面形貌的结构有较大影响。磨合试验中还发现了因齿面副两表面磨损率差形成的负电阻现象。 相似文献
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We focus our study on belt finishing process using a 3D model with multi-asperity abrasive wear on real rough surfaces. The established model allows determining the effect of the local geometry of abrasive grain on the friction coefficient and wear rate. This study shows that the friction coefficient and wear rate increase with the local slopes of the roughness. With the increase of the macroscopic normal load, the wear rate increases rapidly. Such effect is related to the increase of the cutting force of each grain leading to the transition in dominant wear mode from ploughing to wedging and cutting. 相似文献
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The use of low friction coatings like amorphous carbon or metal-doped carbon coatings on machine elements is constantly increasing. Most often, a surface treatment, e.g. grinding and polishing or honing, is required for optimal performance of the coated machine element. This can be time consuming and costly.In this study, the effect of surface roughness on friction and sliding wear of two different coatings, one tungsten containing and one chromium containing coating, were examined using a ball-on-disc test. Ball bearing steel plates were grinded to different surface roughnesses and coated with the two different coatings.The friction was found to depend on surface roughness where the rougher surfaces gave higher friction coefficients. The wear rate for the a-C:W coating was found to be independent of the roughness, whereas the roughness had a strong influence on the wear rate for the a-C:Cr coating. This could partly be explained by a difference in wear mechanism, where fatigue wear was observed for the a-C:Cr coating but not for the a-C:W coating. 相似文献
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《Wear》2002,252(9-10):679-685
The present study was undertaken to evaluate the effect of surface roughness of glass-infiltrated alumina on the abrasive wear of hydroxyapatite using a pin-on-disk tribometer. Hydroxyapatite was used as a model material to simulate tooth enamel. The wear tests were conducted in distilled water at room temperature using a constant sliding speed and three loads to model the normal occlusal contact conditions. The wear volume of polished hydroxyapatite pins increased by more than 20-fold as the average roughness of the alumina disks increased from 14 to 649 nm Ra. No measurable wear was detected on the alumina specimens. The wear surfaces were viewed in a scanning electron microscope (SEM) and were analyzed with X-ray dispersion spectroscopy to determine the extent of surface damage and the wear mechanisms. It is suggested that polished ceramic restorations will cause relatively low enamel wear, while increased roughness could severely abrade and damage the tooth enamel. 相似文献
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Ball-cratering abrasion tests with large abrasive particles 总被引:1,自引:0,他引:1
The application of a ball-cratering method to test three-body abrasive wear of bulk materials in the presence of large abrasive particles has been investigated. Four types of abrasive particles of different sharpness were used to make slurries: glass beads, silica sand, crushed quartz and alumina. All the particles were sieved to a size of 250–300 μm. Two common industrial materials, mild steel and 27% Cr white cast iron, were used as wear samples. Wear rates of metallic samples were determined and the worn surfaces were examined by optical microscopy, SEM and Talysurf profilometry.It was found that the surface roughness of the ball significantly affects the wear rates and the wear mechanisms of the metallic samples. The surface roughness of the ball steadily increased with testing time and was mainly affected by the angularity of abrasive particles. More angular particles generated higher ball surface roughness. It was found that the gradual increase in the ball surface roughness was responsible for non-linearity of wear rates with sliding time. The increasing depth of the wear craters also contributed to this non-linearity as deeper craters facilitate particle entrainment. Three-body rolling wear dominated when the ball was smooth and the contribution of two-body grooving wear increased with increasing the ball roughness. Softer mild steel samples were more affected by the ball roughness changes than the harder white cast iron samples. Wear surface morphology was also affected by the angularity of particles and by the material properties of wear samples. Particle fracture was found in all four groups of abrasives and the angularity of the particles was slightly altered. Therefore, the ball-cratering test, under the testing conditions used, can be considered as a high-stress abrasion test. 相似文献
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Jack C. Roberts 《摩擦学汇刊》2013,56(4):503-510
Ultrahigh-molecular-weight polyethylene (UHMWPE) and polycarbonate pins were slid dry against continuous graphite fiber/epoxy plates in reciprocating multiple-pass wear tests for different values of virgin surface roughness, fiber orientation, and load. Scanning electron photomicrographs of the polymer wear surfaces were combined with three-dimensional graphs of wear rate versus virgin surface roughness and fiber orientation. The types of surface damage observed for UHMWPE at both an 8.9- and 35.6-N load were mild plastic deformation, fatigue of loose particles, and light abrasive cutting. The types of surface damage observed for polycarbonate at either load were massive abrasive plowing and plastic flow of material. The wear debris of UHMWPE consisted of rolled, cut, or extruded particles; for polycarbonate, clumps of transferred plateaus of polymer. The unit pressure times velocity (PV) limit for polycarbonate was reached when samples were slid against the most abrasive counterface transverse to the graphite fibers. 相似文献
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Friction and wear characteristics of a type of polyetheretherketone (PEEK)- based composite were evaluated under two different loading pressures and sliding speeds (P = 1.0 MPa, V = 1.0 m/s and P=2.0 Mpa, V=3.3 m/s). The material was in contact with steel surfaces of two different roughnesses (Ra=0.15 μm and Ra=0.33 μm). Interface temperature, coefficient offriction, depth wear rate, and specific wear rate of the polymer composite changed considerably with the PV value and the counterface roughness. The interface temperature increased with increasing PV value, whereas the friction coefficient decreased. The depth wear rate at the higher PV value was much higher than that at lower PV. In addition, the rougher counterface resulted in a higher friction coefficient, depth wear rate, and specific wear rate, when the PV value was fixed. The effect of counterface roughness on the specific wear rate at the higher PV value was smaller than that at the lower PV. Further variations in friction and wear with testing conditions are discussed along with the corresponding microscopic observations of the worn polymer surfaces and the polymer transferred counterfaces. 相似文献