## 3 Quality Control of Silicon Carbide Printed Part Formation
### Detection and Assessment Techniques
For SiC 3D printing equipment, some high-temperature and high-pressure operating environments require printed parts to possess high tensile strength, flexural strength, compressive strength, and thermal performance indicators, to ensure the product's lifespan. Evaluating these properties requires tensile testing, flexural testing, compressive testing, and thermodynamic testing. During the BJ 3D printing process, tensile test blocks, flexural test blocks, and compressive test blocks are printed alongside the printed parts. After printing, the tensile specimens, flexural specimens, and compressive specimens (see Figure 19a,b) are extracted after depowering for relevant mechanical property testing, among which compressive strength testing is shown in Figure 19c. It should be noted that the design of the aforementioned mechanical property test blocks must comply with national standards for mechanical performance evaluation, including ASTM D638 (tensile testing), ASTM D790 (flexural testing), and ASTM D695 (compressive testing). Common thermal performance evaluation standards include thermogravimetric analysis, differential scanning calorimetry, and thermal conductivity testing, among others [176; 177]. to the produced BJ 3D-printed SiC ceramic parts; therefore, this testing method can be directly applied to the inspection and evaluation of printed parts, significantly reducing unnecessary errors. Some nondestructive testing methods can monitor the quality status of the internal or external surfaces of SiC ceramic printed parts in real time during the manufacturing process of BJ 3D-printed components, and the test results can be used to identify changes in process conditions and optimal process parameters, ensuring the stability and consistency of the printing process. Table 7 summarizes the detection principles of various nondestructive testing methods and provides a comparative analysis of their advantages, disadvantages, and applicable scopes. In summary, after the formation of SiC components via BJ 3D printing, the methods for inspecting and evaluating the components should be weighed from multiple perspectives. These perspectives include not only technical performance, but also economic factors, component complexity, application scenarios, and more. First, the complexity of the printed component will influence the choice of inspection methods. Complex geometries may require nondestructive testing methods such as computed tomography scanning, while simpler-shaped components may only require standard mechanical performance testing. Secondly, from the perspective of size, small components may require high-resolution microscopic inspection tools, whereas large components may need low-resolution methods that can quickly cover the entire part. Furthermore, application scenarios and working environments will affect the focus of inspection; for example, components in aerospace or nuclear industries require high-precision defect detection. In addition, economic cost is also a factor that must be considered. High-precision nondestructive testing can be costly but may be essential for critical functional parts. Finally, efficiency is also a critical aspect, as components produced in large quantities require fast and automated inspection methods.