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991.
Leonardo I. Farfán-Cabrera Cesar D. Reséndiz-Calderón Cesar Sedano de la Rosa 《摩擦学汇刊》2018,61(4):640-647
This article aims to investigate the degradation of physical and tribological properties (friction coefficients and wear resistance) of a dynamic sealing material (silicone rubber [VMQ]) exposed to Jatropha oil (JO), engine mineral oil (EMO), and a blend (B20; 80% EMO–20% JO), separately. JO has demonstrated better lubricating properties than EMO in various mechanical applications; however, the degradation of elastomers by using this oil has not been studied yet, nor have its effect on their tribological properties. The physical degradation was evaluated by conducting static immersion tests (670 h at 25 °C) based on ASTM-D471 and ASTM-D7216 methods. Hence, the changes in mass, volume, tensile and tear strengths, and hardness of VMQ were measured. In addition, creep compliance tests were conducted to determine the changes in viscoelastic properties and the changes in morphology and topography were measured by scanning electron microscopy (SEM) and optical profilometry, respectively. In addition, the compositional changes were determined by Fourier transform infrared (FTIR) analyses to complement the degradation examination. Changes in the friction coefficients were determined by ball-on-disk tests and changes in wear resistance were obtained by accelerated wear tests (microabrasion tests). Finally, VMQ exhibited no significant physical and compositional degradation due to immersion in the three lubricants. However, considerable changes in the friction coefficients and wear resistance were observed; the change in the friction coefficients was minimal using JO. In addition, the coefficients using JO were 50% lower than those for EMO and the changes in wear resistance were lowest after immersion in JO. 相似文献
992.
A. V. Kolomeychenko N. V. Titov V. V. Vinogradov A. M. Stolin P. M. Bazhin 《Welding International》2017,31(9):739-742
The results of investigation of the microstructure of composite coatings produced by carbo-vibroarc surfacing using cermet pastes are presented. It is shown that the composite cermet coating consists of two zones – the main and transition. The main zone of the coating contains the Fe2B hardening phase with nickel and chromium atoms implanted in the crystal lattice of the phase. The zone is situated in the matrix of the solid solution of iron and nickel Ni3Fe. The transition zone of the coating is formed by the mutual diffusion of the coating and the substrate and consists of the (Fe, Ni)2B hardening phase and the Ni3Fe matrix. It is also shown that the hardening phases form plate-shaped grains with thicknesses of 1–4 μm and more than 100 μm long, distributed in the form of colonies throughout the entire volume of the coating zone. In the direction to the transition zone, the shape of the structural components changes to circular with the diameter of up to 5 μm. 相似文献
993.
994.
H. Moll W. Theisen W. Tillmann L. Weber 《Materialwissenschaft und Werkstofftechnik》2005,36(8):365-369
Use of a Scratch Pendulum for Quantification of the Abrasive Behaviour in Machining Stones The machining of natural stones is one of the most demanding applications of today´s cutting technique. Modern stone processing is based on grinding and it is usually done with diamond based tools. The achievable material removal rate is process dependant and mainly determined by tool speed and infeed. The tool durability depends on the adjustment of the parameters to the wear resistance of the processed material. This resistance is a material characteristic value. Using a scratch pendulum, it is possible to determine the energy needed to create a defined scratch and relate it to the induced material loss and the chipped material volume. The analysis provides a value which, after verification by industrial production data, can be seen as characteristic for the material. It therefore enables the quantification of a material dependant scratch resistance. 相似文献
995.
V. I. Kostikov Zh. V. Eremeeva D. A. Slyuta D. L. Yaitskii G. Kh. Sharipzyanova 《Russian Journal of Non-Ferrous Metals》2009,50(2):189-192
The friction of composite materials based on carbon-carbon fiber over the counter-pair made from SG-T siliconized graphite is investigated. The friction conditions that appeared in the working period under definite loads are considered. The structure of the wear products is investigated by electron microscopy. 相似文献
996.
碳化钨喷焊层耐磨性的研究 总被引:2,自引:0,他引:2
本文重点研究了碳化钨与粘结金属的配合比例、碳化物颗粒的粒度、粘结金属的组织成分及其硬度等因素对喷焊层耐磨性的影响,并初步得出某些因素对喷焊层耐磨性的影响规律。还对碳化钨喷焊层在静载与动载磨粒磨损条件下的表面形貌进行了细致地观察与分析,并对磨粒磨损的机理进行了探讨,为正确地选用碳化钨喷焊层提供了依据。 相似文献
997.
钢铜摩擦副表面粗糙度,硬度对摩擦磨损性能的影响 总被引:1,自引:0,他引:1
本文利用双圆盘滚子试验机,研究了钢铜摩擦副试件表面粗糙度、硬度对摩擦磨损性能的影响机理。通过形貌仪和显微镜的检测,分析了不同硬度条件下,表面粗糙度的作用效果。同时,还在扫描电镜上分析了硬度影响曲线的突变状态,提出了在现有生产加工条件下,减少钢铜摩擦副(主要指蜗杆传动副)磨擦,降低磨损的几个有效途径。 相似文献
998.
H13钢热磨损磨面形成层的研究 总被引:1,自引:0,他引:1
用自制销环式热磨损试验机进行热磨损试验,通过扫描电镜、波谱及能谱分析、X-射线衍射等方法对H13钢磨面形成层进行了研究,说明了它的化学组成、形成条件及其在热磨损中的行为。 相似文献
999.
本文对钻头磨损的测量方法以及抑制钻头磨损的效果进行了试验研究。设计了在现场测量钻头磨损的装置和方法,同时在普通和绝缘的状态下进行了钻削对比试验,并在试验中采用了试验速度快而又节省材料和人力的效率判据法,从而得出了在绝缘状态下钻削可有效地抑制钻头磨损的结论。 相似文献
1000.
刀具磨损的切削力监测 总被引:3,自引:0,他引:3
本文用动态分析的方法,对切削力与刀具磨损的内在联系进行了一些理论探索和实验考查,提出了切削力监测刀具磨损的新方法:频段均方值法.经实验、离线分析,该方法可以准确、及时、可靠地监测刀具磨损状态. 相似文献