There are many comparisons in their performance books. The biggest disadvantage of silicon carbide is that it is difficult to sinter!
Silicon nitride is more expensive!
Zirconia has an unstable phase change toughening effect and timeliness. Once this problem is overcome, not only zirconia, but the entire 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 has a higher service 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 operating temperature is lower than the other two. The price is the most expensive.
Alumina ceramics is the earliest ceramic material that is still in use. Low price, stable performance and diversified products. The market must be the largest and largest of alumina, why? Compare the latter two and you will understand.
Mainly compare performance and price. From a market perspective, it is cost-effective.
In terms of price, alumina is the cheapest, and the preparation process of powder raw materials is also very mature. The latter two have obvious disadvantages in this respect, which is also one of the bottlenecks restricting the development of the latter two.
In terms of performance, the mechanical properties such as strength and toughness of silicon nitride and zirconia are far superior to that of alumina. It seems that the price/performance ratio is appropriate, but in fact there are many problems.
Let’s start with zirconia. It has high toughness due to the presence of stabilizers, but its high toughness is time-dependent. For example, zirconia devices lose stability after being placed in air for a period of time, and their performance will Severe drop, even cracking! ! ! Moreover, there is no metastable phase at high temperature, so there is no feature of high toughness. Therefore, the inability to use at high temperature and the timeliness at room temperature severely restrict the development of zirconia. It should be said that it is the smallest in the market.
Speaking of silicon nitride, it is also a popular ceramic in the past two decades, but its finished product preparation process is more complicated than alumina, and it is much better than zirconia in application, but it is still not as good as alumina.