Carbon nanotube toughened hafnium diboride super-high-temperature ceramic composite material and preparing method thereof

Abstract

The invention provides a carbon nanotube toughened hafnium diboride super-high-temperature ceramic composite material and a preparing method thereof. The preparing method comprises the steps of mixing, wherein hafnium diboride powder is mixed with carbon nanotube powder to obtain a mixed powdery material of hafnium diboride and carbon nanotube; sintering, wherein the mixed powdery material is sintered through a spark plasma sintering method to obtain the carbon nanotube toughened hafnium diboride ceramic composite material. According to the preparing method of the carbon nanotube toughened hafnium diboride super-high-temperature ceramic composite material, relative density, hardness, the fracture toughness and the bending strength of the ceramic composite material are improved by combining carbon nanotube toughening and a SPS quick sintering method so as to make the ceramic composite material have a good mechanical property. The carbon nanotube/ hafnium diboride super-high-temperature ceramic composite material prepared through the method is a high-toughness thermal protection material with high temperature resistance, ablation resistance and resistance to heat shocks, and can meet requirements of a thermal protection material at a key position of a high supersonic aircraft.

Description

technical field [0001] The invention relates to a preparation method of a composite material, in particular to a carbon nanotube toughened hafnium diboride ultra-high temperature composite composite material and a preparation method thereof. Background technique [0002] Hypersonic vehicles have the characteristics of fast speed, long flight time, and high maneuverability. Therefore, higher requirements are placed on the temperature resistance and thermal shock resistance of heat-resistant materials. However, there is currently a lack of materials with high melting point, high hardness, and Good thermal conductivity, chemical stability, good oxidation resistance and thermal shock resistance, etc., can be used in extreme environments including hypersonic aircraft hypersonic long-term flight, atmospheric reentry, transatmospheric flight and rocket propulsion system Ultra-high temperature ceramic composite materials. [0003] Hafnium diboride (HfB2) despite its density as high...

AI Technical Summary

Problems solved by technology

But unfortunately, the crystals of this kind of material are connected by strong covalent bonds, and the atomic diffusion is very slow during sintering, which makes the material extremely difficult to sinter and densify, and shows poor toughness under high temperature conditions. Features are not conducive to its development in application

At present, in response to these problems, various SiC, AlN and other additives are introduced to improve its toughness and strong oxygen-friendly phase to improve the oxidation resistance of hafnium diboride in high temperature environments, such as hafnium diboride-SiC-based composite materials; Adding sintering aids to reduce the energy required for the sintering process of hafnium diboride, but the effect is not obvious, and its intrinsic brittleness greatly limits its wide application as a structural component

Images