An adequate hardness of MoS2/Cu composites has not been achieved if these materials are applied under the extreme wear conditions. Therefore, Me-reinforced MoS2/Cu composites were prepared by powder metallurgy （P/M）...An adequate hardness of MoS2/Cu composites has not been achieved if these materials are applied under the extreme wear conditions. Therefore, Me-reinforced MoS2/Cu composites were prepared by powder metallurgy （P/M） methods. The electrical sliding wear properties in the absence or presence of Mereinforced MoS2/Cu composites were tested by HST-100 high speed electric-tribometer. The hardness, electrical conductivity, density, and microstmcture of MoS2/Cu composites were observed. Me-reinforcement MoS2/Cu composites are of good electrical conductivity, while the hardness of Mo-reinforcedment MoS2/Cu composites is about 33.3% higher than that of MoS2/Cu composites. With the addition of Me, composites show better wear properties under high speed and large electric current due to the improvement of hardness. The effects of current intensity and sliding velocity on the wear properties of the tested materials are complicated, and the wear mechanisms of MoS2/Cu composites are mainly abrasive wear and adhesive wear with arc erosion.展开更多
The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact ...The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact system.In this paper,an arcing experimental platform that can accurately control the relative speed and distance of electrodes is built,and the influence of different electrode speeds and electrode distances on arc motion characteristics is explored.It is found that there are three different modes of arc root motion:single arc root motion mode,single and double arc roots alternating motion mode,and multiple arc roots motion mode.The physical process and influence mechanism of different arc root motion modes are further studied,and the corresponding relationship between arc root motion modes and electrode speed is revealed.In addition,to further explore the distribution characteristics of arc temperature and its influencing factors,an arc magnetohydrodynamic model under the relative motion of electrodes is established,and the variation law of arc temperature under the effect of different electrode speeds and electrode distances is summarized.Finally,the influence mechanism of electrode speed and electrode distance on arc temperature,arc root distance,and arc root speed is clarified.The research results enrich the research system of arc dynamic characteristics in the field of sliding electrical contact,and provide theoretical support for restraining arc erosion and improving the service life of the sliding electrical contact system.展开更多
基金Funded by the National Natural Science Foundation of China(No:51371077)Non-ferrous Metal Generic Technology of Henan Collaborative Innovation Center
文摘An adequate hardness of MoS2/Cu composites has not been achieved if these materials are applied under the extreme wear conditions. Therefore, Me-reinforced MoS2/Cu composites were prepared by powder metallurgy （P/M） methods. The electrical sliding wear properties in the absence or presence of Mereinforced MoS2/Cu composites were tested by HST-100 high speed electric-tribometer. The hardness, electrical conductivity, density, and microstmcture of MoS2/Cu composites were observed. Me-reinforcement MoS2/Cu composites are of good electrical conductivity, while the hardness of Mo-reinforcedment MoS2/Cu composites is about 33.3% higher than that of MoS2/Cu composites. With the addition of Me, composites show better wear properties under high speed and large electric current due to the improvement of hardness. The effects of current intensity and sliding velocity on the wear properties of the tested materials are complicated, and the wear mechanisms of MoS2/Cu composites are mainly abrasive wear and adhesive wear with arc erosion.
基金supported by National Natural Science Foundation of China(Nos.U19A20105 and 52077182)。
文摘The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact system.In this paper,an arcing experimental platform that can accurately control the relative speed and distance of electrodes is built,and the influence of different electrode speeds and electrode distances on arc motion characteristics is explored.It is found that there are three different modes of arc root motion:single arc root motion mode,single and double arc roots alternating motion mode,and multiple arc roots motion mode.The physical process and influence mechanism of different arc root motion modes are further studied,and the corresponding relationship between arc root motion modes and electrode speed is revealed.In addition,to further explore the distribution characteristics of arc temperature and its influencing factors,an arc magnetohydrodynamic model under the relative motion of electrodes is established,and the variation law of arc temperature under the effect of different electrode speeds and electrode distances is summarized.Finally,the influence mechanism of electrode speed and electrode distance on arc temperature,arc root distance,and arc root speed is clarified.The research results enrich the research system of arc dynamic characteristics in the field of sliding electrical contact,and provide theoretical support for restraining arc erosion and improving the service life of the sliding electrical contact system.
