Unlock instant, AI-driven research and patent intelligence for your innovation.

A sic doped ta x hf 1-x cCeramics and their preparation methods

A taxhf1-xc, ta1-xhfxc technology, applied in the field of high-temperature ceramics, can solve the problems of poor ceramic uniformity, poor high-temperature oxidation resistance, and inability to form a protective film, achieving low cost, short production cycle, and improved high-temperature oxidation resistance. Effect

Active Publication Date: 2021-08-17
WUHAN UNIV OF SCI & TECH
View PDF10 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this technology uses polycarbosilane to physically mix, and the uniformity of the ceramics is poor, and a good and uniform protective film cannot be formed at high temperatures, resulting in poor high-temperature oxidation resistance of the ceramics.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A sic doped ta <sub>x</sub> hf <sub>1-x</sub> cCeramics and their preparation methods
  • A sic doped ta <sub>x</sub> hf <sub>1-x</sub> cCeramics and their preparation methods

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] A SiC doped Ta x f 1-x C ceramics and methods of making them. The steps of the preparation method described in this embodiment are:

[0029] Step 1, by anhydrous alcohols: acetylacetone: tantalum salt: hafnium salt: the ratio of the amount of substance of carbon source is 2: (0.25~0.29): (1-x): x: (0.2~0.35), 0.01 ≤x≤0.15; mix anhydrous alcohols, acetylacetone, tantalum salts, hafnium salts and carbon sources, and stir at 60-70°C and 500-1200r / min for 1.75-2h to obtain a tantalum-hafnium complex.

[0030] Step 2, heat the tantalum-hafnium complex at 230-240°C for 0.5-0.9h, and distill at 60-120°C for 1-1.5h to obtain Ta 1-x f x C ceramic precursor, 0.01≤x≤0.15.

[0031] Step 3, according to the Ta 1-x f xC ceramic precursor: the mass ratio of silicon source is 1: (0.1~0.5), and described Ta 1- x f x The C ceramic precursor is uniformly mixed with the silicon source to obtain a sol.

[0032] Step 4, according to the sol: ethanol: the mass ratio of deionized wa...

Embodiment 2

[0040] A SiC doped Ta x f 1-x C ceramics and methods of making them. The steps of the preparation method described in this embodiment are:

[0041] Step 1, by anhydrous alcohols: acetylacetone: tantalum salt: hafnium salt: the ratio of the amount of substance of carbon source is 2: (0.29~0.33): (1-x): x: (0.35~0.5), 0.15 ≤x≤0.30; mix anhydrous alcohols, acetylacetone, tantalum salt, hafnium salt and carbon source, stir at 70-80°C and 500-1200r / min for 1.5-1.8h to obtain a tantalum-hafnium complex.

[0042] Step 2, heat the tantalum-hafnium complex at 220-230°C for 0.8-1.2h, and distill at 60-120°C for 1-1.5h to obtain Ta 1-x f x C ceramic precursor, 0.15≤x≤0.30.

[0043] Step 3, according to the Ta 1-x f x C ceramic precursor: the mass ratio of silicon source is 1: (0.4~0.8), and described Ta 1- x f x The C ceramic precursor is uniformly mixed with the silicon source to obtain a sol.

[0044] Step 4, according to the mass ratio of described sol: ethanol: deionized w...

Embodiment 3

[0052] A SiC doped Ta x f 1-x C ceramics and methods of making them. The steps of the preparation method described in this embodiment are:

[0053] Step 1, by anhydrous alcohols: acetylacetone: tantalum salt: hafnium salt: the ratio of the amount of substance of carbon source is 2: (0.33~0.37): (1-x): x: (0.5~0.65), 0.30 ≤x≤0.45; mix anhydrous alcohols, acetylacetone, tantalum salt, hafnium salt and carbon source, and stir at 80-90°C and 500-1200r / min for 1.25-1.5h to obtain a tantalum-hafnium complex.

[0054] Step 2, heat the tantalum-hafnium complex at 210-220°C for 1.1-1.5h, and distill at 60-120°C for 1-1.5h to obtain Ta 1-x f x C ceramic precursor, 0.30≤x≤0.45.

[0055] Step 3, according to the Ta 1-x f x C ceramic precursor: the mass ratio of silicon source is 1: (0.7~1.1), described Ta 1- x f x The C ceramic precursor is uniformly mixed with the silicon source to obtain a sol.

[0056] Step 4, according to the mass ratio of described sol: ethanol: deionized ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
hardnessaaaaaaaaaa
modulusaaaaaaaaaa
Login to View More

Abstract

The invention relates to a SiC doped Ta x f 1‑x C ceramics and methods of making them. The technical solution is: first mix anhydrous alcohols, acetylacetone, tantalum salt, hafnium salt and carbon source, stir, keep warm at 180-240°C, and distill to obtain Ta 1‑x f x C ceramic precursor, 0.01≤x≤0.99. Then the Ta 1‑x f x The C ceramic precursor is uniformly mixed with the silicon source to obtain a sol. Add the ethanol and the deionized water into the sol, stir, and dry to obtain Si-Ta x f 1‑x C ceramic precursor. Then the Si‑Ta x f 1‑x The C ceramic precursor is put into a graphite crucible and placed in a carbonization furnace, heated to 1600-1800°C under an argon atmosphere, kept warm, and cooled to obtain SiC-doped Ta x f 1‑x Cceramics. The invention has the characteristics of simple process, low cost, short production cycle, low energy consumption and high yield, and the prepared SiC doped Ta x f 1‑x C ceramics have high purity, good uniformity and excellent high temperature oxidation resistance.

Description

technical field [0001] The invention belongs to the technical field of high-temperature ceramics. Specifically relates to a SiC doped Ta x f 1-x C ceramics and methods of making them. Background technique [0002] As one of the commonly used transition metal carbides, TaC and HfC have high melting point (>3600°C), high hardness (TaC: 18.9GPa, HfC: 22.1GPa), high modulus (TaC: 537GPa, HfC: 461GPa) and mechanical properties. It has good processing performance and is widely used in high temperature protection in aerospace vehicles. Both TaC and HfC have a NaCl-type crystal structure and can form infinite solid solutions in any proportion. By changing the molar ratio of TaC and HfC, solid solution ceramics with different physical properties can be formed. In this system, when the ratio of TaC to HfC is 4:1, Ta 4 HfC 5 (4215k). [0003] Ta 4 HfC 5 It has good high temperature oxidation resistance only above 1800°C, and the method of introducing heteroatoms can greatl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C04B35/56C04B35/624C04B35/626
CPCC04B35/5622C04B35/624C04B35/626C04B2235/3418C04B2235/3826C04B2235/48
Inventor 董志军成俊李轩科袁观明丛野朱辉张江
Owner WUHAN UNIV OF SCI & TECH