航空摩擦材料混料时间研究

RESEARCH ON THE MIXING TIME OF AIRCRAFT FRICTION MATERIALS

研究了某特定航空摩擦材料混料时间对混合料松装密度和颗粒形貌以及对烧结材料硬度、摩擦磨损性能和微观组织的影响。在特定配料条件下 ,结果表明 ,混料过程使聚集的颗粒分散 ,表面光滑 ,并有割断或磨碎原始颗粒的作用。随着混料时间的增加 ,烧结摩擦材料的硬度降低、摩擦系数增加、材料的磨损量增加 ,而对偶材料的磨损量下降。混料时间为 0～ 8h时 ,混合料松装密度和烧结材料的组织均匀性随混料时间的增加而增加 ,随后不再增加。对所选择的摩擦材料 ,混料 8h可以获得均匀的混合料和组织均匀的烧结材料 ,混合料的松装密度为 1 6 3g/cm3;混料 6～ 10h时 ,烧结材料具有良好的摩擦磨损性能 ,其摩擦系数为 0 192～0 2 0 5 ,总磨损量 (材料磨损 +对偶磨损 )为 3 78～ 3 90 μm/次 ,使用后期无材料崩块现象 ,材料的烧结硬度为 6 2 5～ 6 6 8HRF。

The effects of mixing time on the apparent density of mixed powders and its particle shape,and the hardness,friction and wear properties and microstructure of the sintered aircraft friction materials were studied The results shown that the mixing process scatter the agglomeration of powders,smoothened its surface,and broke up some original particles With the increasing of mixing time,the hardness of the sintered friction material decreases,its friction coefficient and wear loss increases,but the wear loss of the matched material decreases The loose density and homogeneity of the mixed powders increase with the mixing time from 0 to 8 hours,thereafter no more increase was seen by the time increase So 8 hours of mixing time are suitable for obtaining homogenously mixed powders or sintered friction materials The loose density of the mixed powders can reach to 1 63?g/cm 3 Those sintered materials being mixed for 6-10 hours have excellent friction and wear performance Their friction coefficients are ranging in 0 192-0 205 Total wear loss(including matched material) is 3 78-3 90μm per time No spalling occurs over the whole service life The hardness of this sintered material is HRF62 5-66 8