Overview of pressureless sintering fine powder:
Pressureless sintering is a conventional sintering method,A method of sintering by heating the product, which is most commonly used,It is also the simplest sintering method.
Silicon carbide pressureless sintering is widely used
The W series ultra-fine silicon carbide powder produced by the company is mainly used in seal and bulletproof equipment manufacturers due to its high purity, narrow particle size distribution, good fluidity and strong stability.High performance special ceramic materials with high strength, high hardness, high temperature resistance, corrosion resistance, wear resistance and thermal shock resistance are widely used in aerospace, power electronics, mechanical industry, petrochemical industry, ship, pump valve, new energy, scientific research, national defense and military fields.
Main technical specifications:
Name product | Specification and granularity | Appearance color | Purity (%) | Iron (%) | carbon % |
Pressureless sintering of micropowder | W14#. W10#. W7#. W5#. W3.5#. W2.0#. W1.0# W0.5# |
Pure green |
≥99 |
≤0.02 |
≤0.01 |
Other specifications can be customized according to user requirements
Introduction and development of pressureless sintering of silicon carbide
The pressureless sintering equipment is simple and easy to industrial production, which is the most basic sintering method.This method is also widely used in the sintering of nano ceramics, mainly through the selection of sintering system to achieve the densification of green body with the least grain growth.Because in the sintering process, coarsening, densification and grain growth occurThe results show that the activation energy of grain coarsening, billet densification and grain growth are different in different temperature range. By using this relationship, the sintering conditions with high densification rate and slow grain growth can be obtained by controlling the sintering temperature.The control of sintering system is mainly to control the speed of temperature rise (drop), holding time and maximum temperature.The most commonly used pressureless sintering is isokinetic sintering.
Electric heating method is mainly used in pressureless sintering.According to different requirements, there are three kinds of electric heating elements: heat-resistant alloy resistance wire, the maximum heating temperature is 1100 ℃, the general use temperature is ≤ 1000 ℃; silicon carbide resistance rod, the maximum heating temperature is 1550 ℃, the general use temperature is ≤ 1450 ℃, molybdenum disilicide resistance rod, the maximum use temperature in oxidizing atmosphere is 1700 ℃, the general use temperature is ≤ 1600 ℃, and 1700 ℃ in reducing atmosphere can be comparedIt can be used for a long time; the graphite heater can be used in non oxidizing atmosphere with the maximum temperature up to 2000 ℃.
Pressureless sintering is a basic sintering method.This method is not only simple and easy to operate, but also suitable for firing objects of different shapes and sizes, and the temperature system is easy to control.It is precisely because in the pressureless sintering process, the only control means for sintering densification process are temperature and heating rate, so the research on densification process and microstructure development is the most significant and active.
