## 4 Practical Applications and Case Studies
Most studies are still at the laboratory or prototype validation stage, with research efforts primarily focused on microstructural control, mechanical performance evaluation, and process optimization. The technology has not yet been widely adopted in practical applications. Although SiC components fabricated via BJ technology exhibit promising potential for use in critical sectors such as aerospace systems, high-temperature filtration, wear-resistant components, and energy-related equipment, numerous challenges remain in translating laboratory-scale advances into industrial implementation. These challenges include:  
1. Lack of industry standards and regulatory guidelines: At present, there are fewer national or international standards specifically addressing BJ-fabricated ceramics, particularly SiC structural components. This results in the use of disparate testing protocols and performance evaluation criteria across different research groups and industrial entities, making cross-comparison and standardized adoption difficult. Consequently, this lack of standardization hinders the integration of BJ SiC components in high-reliability application scenarios. 2. Insufficient validation of material performance: Although the mechanical properties of BJ-formed SiC components have shown encouraging results, most data are derived from small-scale specimens. Comprehensive performance validation for large-scale or geometrically complex parts remains scarce, limiting confidence in their structural reliability. 3. Process variability and performance reproducibility: Significant fluctuations in binder distribution and post-processing steps can lead to inconsistencies in microstructure and mechanical properties. This lack of reproducibility undermines the reliability assessments required for critical load-bearing applications. 4. High cost and limited economic viability: The overall cost of BJ-produced SiC remains high due to the use of high-purity, ultrafine powders, expensive binder jetting equipment, and energy-intensive high-temperature post-processing. Additionally, long processing times and moderate yields reduce economic competitiveness. Strategies such as powder recycling, process shortening, and yield improvement are needed to enhance cost efficiency. 5. Insufficient engineering-scale validation and environmental adaptability: Current BJ SiC research is largely confined to laboratory-scale samples. There is a lack of long-term performance data under realistic service conditions, such as high-temperature oxidation, thermal shock, corrosive environments, or particle erosion, which are essential for assessing their durability and reliability in demanding operational settings. 6. Controlling process-related defects remains highly challenging. The BJ process inherently suffers from issues such as weak interlayer bonding, non-uniform powder packing density, and trade-offs between layer thickness and feature resolution. During post-processing, even slight variations in parameters such as carbon source incorporation, pyrolysis shrinkage, and silicon infiltration pathways can readily induce defects such as cracking, porosity, warping, and non-uniform silicon infiltration. These issues significantly compromise the final densification and mechanical performance of the printed SiC components.