The chemical performance reactions of silicon nitride precision ceramics to different media

Silicon nitride precision ceramics and advanced ceramics production and processing is a material with high melting point, high hardness, high corrosion resistance and high-temperature stability, which is widely used in aerospace, military industry, nuclear energy, chemical and other fields. The stability and reactivity of its chemical properties directly affect its application effect and service life.

Firstly, silicon nitride precision ceramics have good chemical stability in oxidizing media and can withstand atmospheric oxidation as well as corrosion from alkaline and acidic solutions. In saturated steam, its chemical stability is also very high and it can well resist the erosion of water vapor. However, in strongly oxidizing environments, such as concentrated sulfuric acid and concentrated nitric acid, silicon nitride precision ceramics will be subject to deep chemical erosion, and the erosion rate is extremely fast.

Secondly, the chemical inertness of silicon nitride precision ceramics and advanced ceramics production and processing in inert gases is also very high, especially in high-temperature and high-pressure environments, which can well resist the erosion of active substances such as oxygen, water, sulfur, nitrogen and chlorine. This characteristic makes silicon nitride precision ceramics widely used in high-temperature and high-pressure conditions such as rocket engines and gas turbines.

Secondly, silicon nitride precision ceramics also exhibit excellent chemical stability in organic solvents and can withstand the erosion of various organic solvents such as esters, alcohols, ethers, and hydrocarbons. However, in solvents containing moisture, silicon nitride precision ceramics will be affected by hydrogen oxidation, reducing their chemical stability.

In addition, the industrial ceramic processing technology of silicon nitride precision ceramics will also be subject to a certain degree of chemical erosion in media such as hydrochloric acid, hydrofluoric acid, and sodium hydroxide. In hydrochloric acid, certain corrosion will occur on its surface, but a fluorine-containing SiOF film layer will form to protect the surface. This film layer can enhance the chemical stability of silicon nitride precision ceramics. In hydrofluoric acid and sodium hydroxide, silicon nitride precision ceramics are subject to strong corrosion, which reduces their chemical stability and mechanical properties.

In conclusion, non-standard customized silicon nitride precision ceramics possess excellent chemical stability and inertness, and can resist the chemical erosion of various media. However, it will be affected in some strongly oxidizing, acidic or alkaline media, and its application needs to be selected and designed according to the specific medium environment.