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

A kind of preparation method of low temperature sintered mullite in-situ reinforced silicon carbide porous ceramics

A low-temperature sintering, porous ceramic technology, used in ceramic products, applications, household appliances, etc., to achieve good mechanical strength, improve high-temperature mechanical properties and oxidation resistance.

Active Publication Date: 2018-05-01
JIANGXI UNIV OF SCI & TECH
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this alleviates its further oxidation at high temperature to a certain extent, the SiO 2 The existence of silicon carbide ceramics is still an important factor for the failure of silicon carbide ceramics for long-term use at high temperatures

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 kind of preparation method of low temperature sintered mullite in-situ reinforced silicon carbide porous ceramics
  • A kind of preparation method of low temperature sintered mullite in-situ reinforced silicon carbide porous ceramics
  • A kind of preparation method of low temperature sintered mullite in-situ reinforced silicon carbide porous ceramics

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] First, the Al 2 (SO 4 ) 3 、Na 2 SO 4 and B 2 o 3 The raw materials are compounded according to the molar ratio of 1:4:1 / 6, and mixed with ball milling and passed through a 120-mesh sieve to obtain the mixture A; then, the mixture A, SiC powder and carbon powder are mixed in a mass ratio of 8:100 : The ratio of 20 is carried out batching, crosses 120 mesh sieves and obtains mixture B after mixing ball milling; Adopting dry pressing method is that 200Mpa is at pressure, and pressure-holding time is that under the pressing condition of 120s, above-mentioned mixture B is pressed into green body; Then again After it was dried, it was placed in an electric furnace, and the temperature was raised to 900°C at a rate of 5°C / min for calcination. After reaching the calcination temperature, it was kept for 3 hours, and then cooled with the furnace; finally, the sample was used under the condition of 80°C. Ultrasonic cleaning of tap water, when the Na in the liquid after clean...

Embodiment 2

[0026] First, the Al 2 (SO 4 ) 3 、Na 2 SO 4 and B 2 o 3 The raw materials are compounded according to the molar ratio of 1:4:1 / 6, and the mixture A is obtained by passing through a 120-mesh sieve after mixing and ball milling; then, the mixture A, SiC powder, and graphite powder are mixed in a mass ratio of 10:100 : The ratio of 100 is carried out batching, crosses 120 mesh sieves and obtains mixture B after mixing ball milling; Adopting dry pressing method is that 200Mpa is at pressure, and under the pressing condition that holding time is 90s, above-mentioned mixture B is pressed into green body; Then After drying it, place it in an electric furnace, and heat it up to 1000°C at a rate of 3°C / min for calcination. After reaching the calcination temperature, keep it warm for 5 hours, and then cool it with the furnace; finally, use the sample at 80°C Ultrasonic cleaning of tap water, when the Na in the liquid after cleaning + Concentration does not exceed Na in tap water ...

Embodiment 3

[0029] First, the Al 2 (SO 4 ) 3 、Na 2 SO 4 and B 2 o 3 The raw materials are compounded according to the molar ratio of 1:4:1 / 6, and the mixed material A is obtained by passing through a 120-mesh sieve after mixing and ball milling; then, the mixed material A is mixed with SiC powder and graphite powder in a mass ratio of 2:100 : 0 ratio is carried out batching, crosses 120 mesh sieves and obtains mixture B after mixing ball milling; Adopt dry pressing method to be 150Mpa at pressure, under the pressing condition that holding pressure time is 60s, above-mentioned mixture B is pressed into green body; Then again After it is dried, it is placed in an electric furnace, and the temperature is raised to 1200°C at a rate of 8°C / min for calcination. After reaching the calcination temperature, it is kept for 5 hours, and then cooled with the furnace; finally, the sample is used under the condition of 80°C. Ultrasonic cleaning of tap water, when the Na in the liquid after cleani...

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
flexural strengthaaaaaaaaaa
densityaaaaaaaaaa
flexural strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses a preparation method for mullite in-situ reinforced silicon carbide porous ceramic sintered at low temperature. The preparation method comprises the following steps: subjecting Al2(SO4)3, Na2SO4 and B2O3 to mixing and ball milling so as to obtain a mixture A; then subjecting the mixture A, SiC powder and a pore forming agent to mixing and ball milling so as to obtain a mixture B; subjecting the mixture B to compression molding and then carrying out drying and calcining; and successively carrying out ultrasonic cleaning and drying on the calcined sample. The method promotes low-temperature sintering of silicon carbide porous ceramic; the method overcomes defects in usage of the silicon carbide porous ceramic at high temperature in the presence of a high-temperature binder or sintering agent and is favorable for further improving the porosity of the silicon carbide porous ceramic; and more importantly, SiO2 produced on the surface of silicon carbide due to oxidation is converted into a mullite crystal phase through a high temperature reaction, so the high-temperature mechanical properties and antioxidation performance of the silicon carbide porous ceramic are further improved.

Description

technical field [0001] The invention relates to the technical field of preparation of porous ceramics, in particular to a method for preparing low-temperature sintered mullite in-situ reinforced silicon carbide porous ceramics. Background technique [0002] Due to its high porosity, good corrosion resistance and high temperature resistance, excellent thermal conductivity and other advantages, silicon carbide porous ceramics have been widely used in high temperature soot filtration, molten metal removal of impurities, catalyst carriers and other fields in recent years. Over the years, scholars from various countries have carried out a lot of research work on the preparation and modification of silicon carbide porous ceramics, and achieved fruitful results. Nevertheless, SiC porous ceramics currently suffer from two major problems. [0003] On the one hand, how to sinter silicon carbide powder at a lower temperature is a major problem it faces. Since silicon carbide is a str...

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): C04B35/565C04B38/06
CPCC04B35/565C04B38/068C04B2235/3201C04B2235/3217C04B2235/3409C04B2235/448C04B2235/77C04B2235/80C04B2235/96C04B38/067C04B38/0645C04B38/0074C04B38/0067
Inventor 邓义群沈针
Owner JIANGXI UNIV OF SCI & TECH