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