Integrated polarization imaging system and multi-source fusion framework for thermally induced micro-instability...

Area of Science:

• Materials Science and Engineering
• Optical Engineering
• Aerospace Manufacturing

Background:

• High-performance aerospace components require advanced manufacturing like selective laser melting (SLM).
• Thermally Induced Micro-Instabilities (TIMIs) are critical defects in SLM parts, hindering their application in extreme environments.
• Detecting TIMIs on reflective surfaces is challenging due to process variations and imaging limitations.

Purpose of the Study:

• To develop a high-precision system for detecting and characterizing TIMIs on reflective metal surfaces.
• To overcome limitations of conventional methods in identifying micrometer-scale defects.
• To enhance the reliability and in-service performance of SLM-manufactured aerospace components.

Main Methods:

• An integrated telecentric polarization imaging system was developed.
• A multi-source information fusion and super-resolution reconstruction framework (MMIF-SR) was employed.
• Multi-angle polarization analysis isolated stray light, and deep learning enhanced multimodal data.

Main Results:

• The imaging system achieved a modulation transfer function >0.3 at 100 lp/mm, enabling high-fidelity imaging.
• The MMIF-SR algorithm significantly improved image contrast, increasing information entropy by 2.441 and standard deviation by 15.589.
• Clear visualization of defect contours and micro-features was achieved, enhancing TIMIs detection.

Conclusions:

• The proposed integrated imaging and processing framework effectively detects and characterizes TIMIs on reflective surfaces.
• This technology provides a robust solution for quality control in selective laser melting for aerospace applications.
• The findings contribute to advancing manufacturing engineering for critical aerospace equipment.