First, the basic principle of CT scanning

CT scanning technology is based on the principle of X-ray imaging, and the measured object is projected and collected from multiple angles, and these two-dimensional projection data are reconstructed into high-resolution three-dimensional images by computer algorithm. This technology can penetrate the surface of an object and obtain the detailed information of its internal structure.

Second, the common types of internal defects

In industrial products, common internal defects include pores, cracks, inclusions, looseness, incomplete fusion and delamination. These defects may come from many links in the manufacturing process, such as casting, welding, injection molding, 3D printing, etc. If not found and handled in time, it may lead to product performance degradation or even failure.

Third, the advantages of CT scanning to detect internal defects

1. High-precision detection capability: CT scanning can detect micron-scale defects, which is suitable for the detection of complex structures and micro parts.
　　2. Non-destructive testing: the testing process will not damage the sample, which is especially suitable for valuable or irreplaceable samples.

3. Three-dimensional visualization analysis: it can provide three-dimensional distribution images of defects, which is convenient for analyzing the position, shape and size of defects.

4. Quantitative analysis function: Through software measuring tools, the parameters such as volume, area and length of defects can be accurately measured.
　　5. comprehensiveness and repeatability: the whole sample can be comprehensively tested, and repeated tests are supported to verify the consistency of the results.

Fourth, CT scanning detection process

CT scanning detection generally includes the following steps:
　　1. Sample preparation: place the sample to be tested on the scanning platform to ensure its stability.

2. Parameter setting: Set appropriate X-ray voltage, current and scanning angle according to sample material, density and detection requirements.

3. Data acquisition: By rotating the sample or the radiation source, the projection images from multiple angles are acquired.

4. Image reconstruction: 3D reconstruction of the collected data with professional software.

5. Defect analysis: Identify internal defects and evaluate their severity through image comparison and analysis.

6. Report output: generate test report to provide basis for subsequent process improvement or quality control.

V. Application cases

In the manufacture of aero-engine blades, CT scanning can be used to detect internal shrinkage cavities and cracks to ensure the structural integrity of key components. In the field of electronic packaging, CT technology can identify the cavity problem of solder joints in chips; In the production of medical implants, it can effectively detect tiny bubbles in titanium alloy parts and ensure the safety of implantation.

VI. Conclusion

With the continuous development and popularization of CT technology, its application in internal defect detection is increasingly extensive. It not only improves the detection efficiency and accuracy, but also provides strong support for product quality control and process optimization. In the future, combined with artificial intelligence and big data analysis, CT scanning will play a greater role in automatic defect identification and classification, and promote nondestructive testing to a new stage of intelligence.