Ti(CN)-based self-lubricating cermet cutter material added with alumina-coated calcium fluoride composite powder and preparation method thereof

Abstract

The invention relates to a Ti(CN)-based self-lubricating cermet cutter material added with alumina-coated calcium fluoride composite powder and a preparation method thereof. The cutter material is prepared from the following main raw materials comprising, by mass percentage, 1-20% of the alumina-coated calcium fluoride composite powder, 0.25-5% of magnesium oxide, 3-15% of molybdenum, 8-20% of nickel, 8-20% of cobalt and the balance Ti(CN) through hot pressing and sintering, wherein the sum of the mass percentages of the component is 100%. The cutter material is of a multi-layer core-shell microstructure with CaF2 as a core, Al2O3 as a middle layer and a metal phase as a shell; and CaF2 on the inner layer is effectively protected, the problem that the mechanical properties of a cutter arereduced due to addition of a solid lubricant is solved, and the problems of internal interface stress concentration of the cutter and abnormal growth of cermet grains are relieved. The obtained cuttermaterial has good lubrication performance and mechanical properties, and the hardness and fracture toughness performance are greatly improved.

Description

technical field [0001] The invention relates to a Ti(CN)-based self-lubricating cermet tool material added with alumina-coated calcium fluoride composite powder and a preparation method thereof, belonging to the technical field of Ti(CN)-based cermet tool materials. Background technique [0002] Ti(C,N)-based cermet is a new type of particle-reinforced composite material that appeared in the early 1970s; it uses Ti(C,N) as the hard phase, and adds WC, TaC and other refractory metal carbides at the same time. Compounds or nitrides, and a class of composite materials that use Ni or Co as a binder. Compared with traditional WC-based cemented carbide, Ti(C,N)-based cermet tools have better wear resistance, thermal stability, high temperature red hardness at 700-1100°C, oxidation resistance and adhesion resistance , high cutting temperature, its cutting speed and service life are increased by 3 to 10 times and 2 to 5 times respectively, and the main raw material resources are ab...

AI Technical Summary

Problems solved by technology

Chinese patent document CN107602097A discloses a kind of Al 2 o 3 / Ti(C,N) nano-based ceramic tool material and preparation method thereof, consisting of the following components: nano-CaF 2 @Al 2 o 3 Coated composite powder 1-30%, MgO 0.1-3%, Ti(C,N) 1-55%, the balance is Al 2 o 3 , % is the volume percentage; the invention adds nano-encapsulated solid lubricants to effectively improve the shortcomings of the poor mechanical properties of self-lubricating ceramic cutters; but CaF 2 @Al 2 o 3 The coated composite powder is a single phase in the tool material, and its physical properties are mainly determined by the shell Al 2 o 3 OK, but due to the CaF inside the coating 2 Coefficient of thermal expansion greater than that of Al 2 o 3 , then Al 2 o 3 Compressive stress is generated, resulting in residual stress, which reduces the mechanical properties such as the strength of the tool material

Images