Mechanical properties and microstructure of Al2O3/TiC based self-lubricating ceramic tool with CaF2@Al (HO)3. (September 2018)

• Record Type: Journal Article
• Authors: Chen, Zhaoqiang; Ji, Lianggang; Guo, Niansheng; Guo, Runxin
• Is Part Of: International journal of refractory metals & hard materials. Volume 75(2018)
• Page Start: 50
• Page End: 55
• Publication Date: 2018-09
• Subjects: Shell-core coating -- Self-lubricating tool -- Microstructure -- Performance test; Heat resistant alloys -- Periodicals; Refractory materials -- Periodicals; Metallography -- Periodicals; Alliages réfractaires -- Périodiques; Matériaux réfractaires -- Périodiques; Métallographie -- Périodiques; Heat resistant alloys; Metallography; Refractory materials; Periodicals; Electronic journals; 669.73
• DOI: 10.1016/j.ijrmhm.2018.04.001
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: The CaF2 @Al2 O3 coated powder with shell-core structure was prepared by liquid-phase non-uniform nucleation method. Based on the successful preparation of Al(OH)3 coated CaF2 powder, Al2 O3 /TiC self-lubricating tool was prepared by wet dispersion mixing and vacuum hot pressing sintering process. The microstructure and performance of the self-lubricating ceramic tool with different volume content of CaF2 @Al(OH)3 coated powders were investigated. The results show that when the CaF2 @Al2 O3 content is 10 vol%, the comprehensive mechanical properties of Al2 O3 /TiC/CaF2 @Al2 O3 tool materials is the best, the hardness is 16.86 GPa, the flexural strength is 662 MPa, and the fracture toughness is 6.34 MPa·m 1/2 . Compared with the traditional Al2 O3 /TiC/10 vol%CaF2 self-lubricating ceramic cutting tools, Al2 O3 /TiC/10 vol% CaF2 @Al2 O3 ceramics in flexural strength, fracture toughness and hardness were increased 19.06%, 36.9%, 12.25%, of which the most obvious increase in fracture toughness. Highlights: The CaF2 @Al2 O3 coated powder with shell-core structure was successfully prepared by non-uniform nucleation method. Appropriate amount of CaF2 @Al2 O3 powder can improve the mechanical properties of the tool material. The addition of CaF2 @Al2 O3 powder to the Ceramics matrix significantly improved the microstructure of the material.