Nanostructure tungsten-zirconium carbide alloy and preparation method thereof

Abstract

The invention discloses a nanostructure tungsten-zirconium carbide alloy. The nanostructure tungsten-zirconium carbide alloy comprises the following components by weight percentage: 98-99.8% of tungsten, and 0.2-2.0% of zirconium carbide with the grain diameter of 5-300 nm, wherein the zirconium carbide grains are mostly uniformly distributed in the interiors of the tungsten crystal grains. The invention further discloses a preparation method of the alloy. The prepared alloy has good mechanical property and high-temperature stability; the zirconium carbide nanograins can be uniformly distributed in the interiors of the tungsten crystal grains, so that stress concentration and embrittlement generated by coarse particle in the tungsten crystal grains are avoided; the strength and high-temperature performance can be improved by pinning dislocation, and meanwhile, the toughness is ensured.

Description

Technical field [0001] The invention is the field of material science and technology, which involves a nano-structure tungsten-carbonized alloy alloy, and the invention also involves the manufacturing method of the alloy. Background technique [0002] Due to its high melting point (about 3410 ° C) and high high temperature mechanical properties, metal tungsten is widely used in high temperature components, lighting, national defense and other fields. In addition, it also has the advantages of low thermal expansion coefficient and sputtering.Stacking candidate wall materials.However, there are disadvantages such as low temperature and crispyness and crushing crispy, which causes it to be crispy and difficult to process, which affects its application range.In addition, the intensity of pure tungsten will be clearly reduced with the rise of temperature, and pure tungsten will also be crystallized and crispy at high temperature. [0003] In order to improve the intensity and toughnes...

AI Technical Summary

Problems solved by technology

However, tungsten has disadvantages such as low-temperature brittleness and recrystallization brittleness, which make it prone to brittle fracture and difficult to process, which affects its application range.

In addition, the strength of pure tungsten will obviously decrease with the increase of temperature, and pure tungsten will be recrystallized and embrittled at high temperature.

[0003] In order to improve the strength and toughness of metal tungsten, people have made some attempts and efforts, such as adding high melting point second phase particles to tungsten, such as titanium carbide and zirconium carbide , lanthanum oxide, yttrium oxide, etc., can play the role of dispersion strengthening and refining tungsten grains, can increase the high temperature strength and recrystallization temperature of tungsten, but reduce the toughness of tungsten

The main reason is that these particles are large in size and mostly distributed at grain boundaries, which will lead to stress concentration and easily become the starting point of cracks, thus affecting the toughness

[0004] Yujin Wang published a paper entitled "Influence of ZrC content on the elevated temperature tensile properties of ZrCp / W composites", "Materials Science and Engineering A", 528 (2011) 1805-1811 ("The effect of ZrC content on the high temperature tensile properties of ZrC particles / tungsten composite materials", "Material Science and Engineering A", Volume 525, 2011, pages 1805-1811) Among the reported ZrC particle-reinforced tungsten materials, the particle size of ZrC is at the micron level, and the addition of ZrC is 20-50% volume fraction, which is beneficial to reduce thermal conductivity and high temperature ablation resistance, but its toughness is very low

[0005] Another example is Zhou Yu et al. in patent CN99120173 discloses a preparation method of zirconium carbide particles reinforced tungsten composite material, the volume fraction of carbide particles is 10%~50 %, can improve the high temperature strength, oxidation resistance and ablation resistance of tungsten, and has low thermal conductivity, but the carbide particles are high in content and large in size, resulting in reduced toughness

Not suitable for applications requiring materials with good toughness, high temperature strength and high thermal conductivity

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