Mechanical properties, microstructure and crack healing ability of Al2O3/TiC/TiB2/h-BN@Al2O3 self-lubricating ceramic tool material

To prepare a self-lubricating ceramic tool with excellent mechanical properties and crack healing ability, the [email protected]2O3 solid lubricant core-shell structure was prepared by heterogeneous nucleation method, added into Al2O3/TiC matrix together TiB2. Examination of micro-morphology phase composition found that surface h-BN coated Al(OH)3 at first, after calcination 1200 °C, dense uniform Al2O3 shell formed. At same time, effects addition on material were studied. The improved relative to than those h-BN. optimal content 5 vol%. In friction wear test, in particles can be stripped form lubricating film surface, which plays good role reducing resisting wear. ability studied prefabricating cracks length 400 ?m surface. After heat treatment 700 °C for 60 min, completely healed, flexural strength restored 90% smooth samples. oxidation TiB2 materials is main reason healing.