The biggest disadvantage of silicon carbide is that it is difficult to sinter!
Silicon nitride is more expensive!
The phase transformation and toughening effect of zirconia is unstable and sometimes effective. Once this problem is overcome, not only zirconia, the whole ceramic field may have a breakthrough! .
Alumina is more common and cheaper, and has good temperature resistance.
Zirconia has better wear resistance than alumina and higher temperature, but its thermal shock resistance is worse than alumina.
Silicon nitride has good comprehensive properties such as wear resistance and thermal shock resistance, but the use temperature is lower than the other two. The most expensive.
Alumina ceramics are the earliest applied ceramic materials. Cheap price, stable performance and diversified products. The market is definitely the largest and largest alumina, why? Compare the latter two and you will understand.
It is mainly compared in terms of performance and price. Then it is cost-effective from a market perspective.
In terms of price, alumina is the cheapest, and the powder raw material preparation process is also very mature. The latter two have obvious disadvantages in this regard, which is also one of the bottlenecks that restrict the development of the latter two.
In terms of performance, the mechanical properties such as strength and toughness of silicon nitride and zirconia are much better than those of alumina. It seems that the cost performance is appropriate, but in fact there are many problems.
From the perspective of zirconia, it has high toughness due to the presence of stabilizers, but its high toughness is time-sensitive. For example, after the zirconia device is left in the air for a period of time, it will lose stability and performance will Severe drop or even cracking! !! !! Moreover, there is no metastable phase at high temperature, so there is no high toughness. Therefore, the use of high temperature and room temperature can seriously restrict the development of zirconia. It should be said that it is the smallest of the three markets.
Speaking of silicon nitride, it has also been a popular ceramic in the past two decades, but its finished product preparation process is also more complicated than alumina, which is much better than zirconia, but it is still not as good as alumina.
Post time: Dec-26-2019