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Aiming to improve the performance of self‐lubricating ceramic tools, an advanced self‐lubricating ceramic composite was developed. Core‐shell structure CaF2@Al2O3 powders were synthesized by liquid‐phase non‐uniform nucleation method. Al2O3/Ti(C,N)/CaF2@Al2O3 composite made by adding CaF2@Al2O3 powders exhibited notable improvements in microstructure and mechanical properties as compared with Al2O3/Ti(C,N)/CaF2 composite made by adding uncoated CaF2 powders. The core‐shell coated self‐lubricating ceramic tool with different content of CaF2@Al2O3 was designed and prepared by hot pressing sintering process. The results show that when the content of CaF2@Al2O3 is 10 vol%, The composite has the best mechanical properties, the flexural strength, and the fracture toughness and the hardness is 680 MPa, 6.50 MPa·m1/2, and 17.29 GPa. Compared with the tool material with only CaF2 solid lubricant added, the above performances were increased by 8.91%, 29.48%, and 14.50% respectively. The influence of different CaF2@Al2O3 content on the physical and mechanical properties and microstructure of the tool material was analyzed. [ABSTRACT FROM AUTHOR]

Aiming at the contradiction between the lubricating performance and mechanical performance of self-lubricating ceramic tools. CaF2@Al(OH)3 particles were prepared by the heterogeneous nucleation method. An Al2O3/Ti(C,N) ceramic tool with CaF2@Al2(OH)3 particles and ZrO2 whiskers was prepared by hot press sintering (frittage). The cutting performances and wear mechanisms of this ceramic tool were investigated. Compared with the Al2O3/Ti(C,N) ceramic tool, the Al2O3/Ti(C,N)/ZrO2/CaF2@Al(OH)3 ceramic tool had lower cutting temperatures and surface roughness. When the cutting speed was increased from 100 m/min to 300 m/min, a lot of CaF2 was smeared onto the surface of the ceramic tool, and the flank wear of the Al2O3/Ti(C,N)/ZrO2/CaF2@Al(OH)3 ceramic tool was reduced. The main wear mechanisms of the Al2O3/Ti(C,N)/ZrO2/CaF2@Al(OH)3 ceramic tool were adhesive wear and micro-chipping. The formation of solid lubricating film and the improvement of fracture toughness by adding ZrO2 whiskers and CaF2@Al(OH)3 were important factors for the Al2O3/Ti(C,N)/ZrO2/CaF2@Al(OH)3 ceramic tool to have better cutting performances. [ABSTRACT FROM AUTHOR]

Aiming at the contradiction between the lubricating performance and mechanical performance of self-lubricating ceramic tools. CaF 2 @Al(OH) 3 particles were prepared by the heterogeneous nucleation method. An Al 2 O 3 /Ti(C,N) ceramic tool with CaF 2 @Al 2 (OH) 3 particles and ZrO 2 whiskers was prepared by hot press sintering (frittage). The cutting performances and wear mechanisms of this ceramic tool were investigated. Compared with the Al 2 O 3 /Ti(C,N) ceramic tool, the Al 2 O 3 /Ti(C,N)/ZrO 2 /CaF 2 @Al(OH) 3 ceramic tool had lower cutting temperatures and surface roughness. When the cutting speed was increased from 100m/min to 300m/min, a lot of CaF 2 was smeared onto the surface of the ceramic tool, and the flank wear of the Al 2 O 3 /Ti(C,N)/ZrO 2 /CaF 2 @Al(OH) 3 ceramic tool was reduced. The main wear mechanisms of the Al 2 O 3 /Ti(C,N)/ZrO 2 /CaF 2 @Al(OH) 3 ceramic tool were adhesive wear and micro-chipping. The formation of solid lubricating film and the improvement of fracture toughness by adding ZrO 2 whiskers and CaF 2 @Al(OH) 3 were important factors for the Al 2 O 3 /Ti(C,N)/ZrO 2 /CaF 2 @Al(OH) 3 ceramic tool to have better cutting performances., Competing Interests: The authors declare no conflict of interest.