Polysilazane is not only a coating material but also a key polymer precursor for the preparation of high-performance ceramic matrix composites (CMCs). The polymer-derived ceramic (PDC) route offers solutions for forming ceramic components with complex geometries that are difficult to achieve through conventional processes.

From a technical perspective, the core process of the precursor conversion method includes: shaping liquid polysilazane into the desired form through spinning, infiltration, or molding processes, followed by a curing (infusibilization) step to fix the shape, and finally pyrolysis at high temperatures to convert it into ceramic. Ceramic fiber preparation represents one typical application: after spinning, polysilazane can be processed into continuous SiCN fibers through controlled curing and pyrolysis temperature profiles. Such fibers exhibit excellent high-temperature resistance and chemical stability, making them important reinforcements for CMCs. In terms of ceramic matrix infiltration, the polymer infiltration and pyrolysis (PIP) process employs multiple infiltration-pyrolysis cycles to gradually fill SiCN ceramic matrix into carbon fiber or silicon carbide fiber preforms, ultimately forming C/SiC or SiC/SiC composites.

In terms of performance data, ceramic yield is a key parameter affecting densification. The addition of active fillers such as titanium or aluminum can promote ceramic phase formation during pyrolysis, increasing the yield to higher levels. The tensile strength of ceramic fibers can reach high levels, meeting structural reinforcement requirements. Regarding thermal stability, SiCN ceramics maintain structural integrity above 1300°C, making them suitable for long-term high-temperature service environments.

Application areas include hot-section components of aero-engines, such as turbine blades and combustor liners, which must operate long-term under high temperature, high pressure, and corrosive combustion gas environments; spacecraft re-entry thermal protection systems, where leading edges of hypersonic vehicles must withstand aerodynamic heating of 1000 to 1500°C; and the nuclear industry, where the radiation resistance of SiCN ceramics offers potential for use in nuclear reactor structural materials.

The industrialization process still faces several challenges. Uniform coating or infiltration processes for large-scale components require precise control of polysilazane rheological properties and curing behavior; long-term service performance evaluation requires the establishment of comprehensive accelerated aging test methods and life prediction models; cost control and import substitution are important prerequisites for promoting large-scale application. As preparation processes continue to be optimized and performance data accumulate, the application prospects of polysilazane in the advanced ceramics field are worth anticipating.

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