A low-temperature preparation method of refractory metal carbide solid solution powder

Abstract

The invention relates to the technical field of high-temperature ceramic materials, and provides a low-temperature preparation method of refractory metal carbide solid solution powder, using Ca, Al melt or Ca-Al melt as a flux, and mixing it with metal carbide, at 800-1400 The temperature is kept at ℃ for 2-12 hours, and the refractory metal carbide solid solution powder is obtained after acid leaching. Beneficial effects of the present invention: metal melt is used as the flux, and the liquid metal melt can be used as a diffusion channel between carbides, which greatly improves the reaction rate. Preparation of single-phase refractory metal carbide solid solution; the temperature required by the present invention is much lower than that of the high-temperature solid solution method, with low equipment requirements, low energy consumption, and easy industrial production; compared with the carbothermal reduction method, the required temperature of the present invention is higher Low, and there is no problem of inhomogeneous product phase; due to the strong deoxidation ability of elemental calcium and aluminum, the product purity can be further improved.

Description

technical field

[0001] The invention relates to the technical field of high-temperature ceramic materials, in particular to a low-temperature preparation method of refractory metal carbide solid solution powder. Background technique

[0002] Refractory carbide is an intermetallic compound formed by carbon atoms entering the intergranular point of the refractory metal lattice. It has the characteristics of covalent solid, ionic crystal and refractory metal. It is widely used in drill tools, mining operations and High temperature parts field. Since TiC, ZrC, HfC, VC, NbC, TaC, CrC, MoC, WC and other refractory carbides have the same NaCl type face-centered cubic crystal system, they can form single-phase refractory metal carbides by solid solution at high temperature Solid solutions, such as binary carbides HfxTa1-xC, ternary carbides (Ti, Zr, Nb) C, high entropy carbides (Ti, Zr, Hf, Nb, Ta) C, (Zr, Hf, Nb, Ta, Mo)C and so on.

[0003] This multi-component carbide is a new...

Examples

Embodiment 1

[0033] Mix pure HfC and TaC with a ball mill in a molar ratio of 1:4, then mix the mixed powder with metal calcium with a mass ratio of 1:0.5 and stir evenly, then heat to 1300°C for 4 hours under an argon atmosphere, and obtain after acid leaching. Ta 4 HfC5 powder. Detected by XRD, such as figure 1 shown, showing that the product is a single phase of pure Ta 4 HfC 5 .

Embodiment 2

[0035] pure TiO 2 , Nb 2 O 5 , Ta 2 O 5 , C were mixed by ball milling in a molar ratio of 2:1:1:20, reacted in an argon atmosphere at 1600 ° C for 4 hours, and obtained the equimolar ratio composite powder of TiC, NbC, and TaC by carbothermal reduction. The composite powder was then mixed with metal calcium with a mass ratio of 1:0.6, then heated to 1200 °C for 10 hours in an argon atmosphere, and TiNbTaC was obtained after acid leaching. 3 powder. Detected by XRD, such as figure 2 shown, showing the product as pure TiNbTaC in a single phase 3 .

Embodiment 3

[0037] Mix pure ZrC, HfC, NbC and TaC with a ball mill in a molar ratio of 1:1:1:1, then mix the mixed powder with metal calcium in a mass ratio of 1:0.5 and stir evenly, then heat to 1400°C in an argon atmosphere After holding for 2 hours, ZrHfNbTaC was obtained after acid leaching 4 powder. Detected by XRD, such as image 3 shown, showing the product as pure ZrHfNbTaC in a single phase 4 .

technical field

[0001] The invention relates to the technical field of high-temperature ceramic materials, in particular to a low-temperature preparation method of refractory metal carbide solid solution powder. Background technique

[0002] Refractory carbide is an intermetallic compound formed by carbon atoms entering the intergranular point of the refractory metal lattice. It has the characteristics of covalent solid, ionic crystal and refractory metal. It is widely used in drill tools, mining operations and High temperature parts field. Since TiC, ZrC, HfC, VC, NbC, TaC, CrC, MoC, WC and other refractory carbides have the same NaCl type face-centered cubic crystal system, they can form single-phase refractory metal carbides by solid solution at high temperature Solid solutions, such as binary carbides HfxTa1-xC, ternary carbides (Ti, Zr, Nb) C, high entropy carbides (Ti, Zr, Hf, Nb, Ta) C, (Zr, Hf, Nb, Ta, Mo)C and so on.

[0003] This multi-component carbide is a new...

Examples

Embodiment 1

[0033] Mix pure HfC and TaC with a ball mill in a molar ratio of 1:4, then mix the mixed powder with metal calcium with a mass ratio of 1:0.5 and stir evenly, then heat to 1300°C for 4 hours under an argon atmosphere, and obtain after acid leaching. Ta 4 HfC5 powder. Detected by XRD, such as figure 1 shown, showing that the product is a single phase of pure Ta 4 HfC 5 .

Embodiment 2

[0035] pure TiO 2 , Nb 2 O 5 , Ta 2 O 5 , C were mixed by ball milling in a molar ratio of 2:1:1:20, reacted in an argon atmosphere at 1600 ° C for 4 hours, and obtained the equimolar ratio composite powder of TiC, NbC, and TaC by carbothermal reduction. The composite powder was then mixed with metal calcium with a mass ratio of 1:0.6, then heated to 1200 °C for 10 hours in an argon atmosphere, and TiNbTaC was obtained after acid leaching. 3 powder. Detected by XRD, such as figure 2 shown, showing the product as pure TiNbTaC in a single phase 3 .

Embodiment 3

[0037] Mix pure ZrC, HfC, NbC and TaC with a ball mill in a molar ratio of 1:1:1:1, then mix the mixed powder with metal calcium in a mass ratio of 1:0.5 and stir evenly, then heat to 1400°C in an argon atmosphere After holding for 2 hours, ZrHfNbTaC was obtained after acid leaching 4 powder. Detected by XRD, such as image 3 shown, showing the product as pure ZrHfNbTaC in a single phase 4 .

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