Mixed crystal Ti (C, N)-based metal ceramic material and preparation method thereof

Abstract

The invention discloses a mixed crystal Ti (C, N)-based metal ceramic material and a preparation method thereof. According to the mixed crystal Ti (C, N)-based metal ceramic material and the preparation method thereof, two kinds of Ti (C, N) with different granularities are combined, Ti (C, N) particles with different granularities serve as a core, TaC, NbC, Mo2C and other carbides form a uniform outer ring structure with the core, finally, a typical core-shell structure is formed, the core-shell structures with different sizes form a mixed crystal structure, and the defect that hardness and toughness of a single and uniform crystal structure cannot be considered at the same time is overcome; and a Ti (C, N) solid solution is an infinite solid solution, when the N / C ratio is larger than 5 to 5, the activity of N is increased, pores are easily formed, and by adopting the combination of Ti (C0.5, N0.5) and Ti (C0.7, N0.3), local pores caused by the fact that the N / C ratio is larger than 5 to 5 are avoided.

Description

technical field [0001] The invention belongs to the field of Ti(C,N)-based cermets, in particular to a mixed crystal Ti(C,N)-based cermet material and a preparation method thereof. Background technique [0002] Ti(C,N)-based cermets have high hardness, good chemical stability and good high-temperature red hardness. The above characteristics are the advantages of cermets in the field of metal or wood processing. However, the flexural strength and fracture toughness of most Ti(C,N)-based cermets are inferior to those of traditional cemented carbide materials, which limits their application in the field. [0003] The physical and chemical properties of the low flexural strength of cermets are mainly due to the insufficient wetting of the ceramic phase Ti(C, N) by the conventional binder phases Co and Ni, so that after sintering, the interface strength between the binder phase and the ceramic phase of the cermet is weaker. Weak, prone to failure under certain thermal shock or i...

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Problems solved by technology

[0004] A lot of research has also been done on improving the fracture toughness of cermets. The strengthening and toughening of cermets has been achieved by introducing whiskers and carbon nanotubes into Ti(C,N)-based cermets. The above toughening measures lead to increased production costs. , The difficulty of process control increases, which is not conducive to the realization of industrial production; the toughening of mixed crystal Ti(C, N)-based cermets through plate-like carbide solid solution is firstly made of Ti powder, W powder, Ti0 2 Powder, Ni powder, Mo powder and graphite powder are used as raw materials for high-energy ball milling to prepare prefabricated platy carbide solid solution powder, and the prefabricated platy carbide solid solution powder is mixed with cermet components to prepare mixed crystal cermet materials, prefabricated platy carbide Add Ti, W and TiO to solid solution powder 2 Metals and oxides such as Ti and W will be carbonized during alloying, and TiO 2 The oxide needs to be reduced and carbonized, which increases the difficulty of controlling the preparation process of cermet materials, and high-energy ball milling is not suitable for industrial production; it is prepared by mixing low-bonding phase cermet particles (30-200 μm) and high-bonding phase cermet particles (60-300 μm) The island-like structure hardens Ti(C,N)-based cermets with high toughness. The preparation of low-bond phase cermet particles and high-bond phase cermet powders from this material has the defect of inherently poor toughness of cermets. It is difficult to homogenize large-grain raw materials by ball milling, which increases the difficulty of the material preparation process

[0005] In view of the above methods of improving the flexural strength and providing toughness of cermets, it will obviously increase the production cost or increase the difficulty of process control, which is difficult for industrial production

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