复压复烧对烧结减摩Cu-Ti3SiC2导电材料性能的影响

利用粉末冶金技术制备了10%Ti3SiC2颗粒增强Cu基减摩、导电材料。以200,400和500 MPa的压力对烧结试样进行复压,然后复烧,以提高材料的密度。通过测量试样的密度、硬度和电阻率,探索了复压复烧对材料性能的影响,并对试样进行了通电和不通电情况下的摩擦、磨损试验。结果表明,经400 MPa复压复烧后,材料的密度和硬度得到显著提高,密度由7.309 g·cm-3增加至7.712 g·cm-3,而硬度则达到HB 114,导电性能和减摩、抗磨能力也因此得到了改善,摩擦系数有所降低,磨损量减少了68%。与未带电的情况相比,带电时的摩擦因数相对较小,但磨损量则较大。在带电磨损实验过程中,摩擦副的温度升高使样品表面的铜基体部分氧化,并起到了润滑作用,从而降低了摩擦因数。

Influence of Double Press-Double Sinter on Properties of Sintered Anti-Friction Cu-Ti3SiC2 Electric Conducting Material

An anti-friction Cu-10 wt%Ti3SiC2 electric conducting composite material was prepared by powder metallurgy.Its density was enhanced by double press-double sinter technique using compacting pressures of 200,400 and 500 MPa.Effect of double press-double sinter on density,hardness and electrical resistivity of the composite was studied.Friction and wear experiments were carried out with and without passing electric current.After double press-double sinter with 400 MPa,both density and hardness of the composite increased significantly,the density increased from 7.309 g · cm-3 to 7.712 g · cm-3,the hardness reached at HB 114,the friction coefficients decreased and wear volume reduced by 68%.The friction coefficients obtained from experiments that carried out under electrical current were lower than those obtained from experiments carried out without electrical current,while the wear volumes were higher.The temperature elevation during the experiment,which carried out under electrical current,led to partial oxidation of the surface Cu and thus reduced the friction coefficient due to the lubrication effect of the oxide.