CP Dofn JA 23-2049267-27 273 岛A+翻cA apainst 100 um SCpartices: (a)SN A: ()Si, NaA+SC (c)Sl, B; (d)S NrB+SC:(e)99 8 Al-O:C.P. Do&m. J.A. Hawk/ Wear203-204 119547) 267-277 213 fig. 4. Wear surfaces following abrasion against 100 tmt Sii patticks: (a) Si,N& (b) Si,N,-A + Sic; (c) S&N.-B; (d) S&N,-B + Sii; (e) 99.8%40,: (f) A1203 + SC,,; and (g) 99.5% A1203