Benchmarking of Nondestructive Testing for Additive Manufacturing

Area of Science:

• Materials Science and Engineering
• Manufacturing Technology
• Non-Destructive Testing

Background:

• Additive Manufacturing (AM), particularly Selective Laser Melting (SLM), faces challenges in defect detection for critical applications.
• Nondestructive testing (NDT) methods are not yet standardized or widely adopted for AM parts.
• Complex geometries and diverse defect types (porosity, cracking, lack of fusion) hinder reliable inspection.

Purpose of the Study:

• To evaluate the effectiveness of various NDT techniques for defect detection in complex SLM-manufactured parts.
• To assess the detectability of real and artificial defects in AISI 316L stainless steel components.
• To determine if a single NDT method is sufficient or if a multi-technique approach is necessary.

Main Methods:

• Dye penetrant testing
• Infrared thermography
• Immersion ultrasonic testing
• Eddy current testing
• X-ray microcomputed tomography

Main Results:

• Each NDT technique demonstrated varying capabilities in detecting specific defect types.
• No single method was capable of identifying all assessed defects.
• X-ray microcomputed tomography provided detailed internal defect visualization.
• Surface and near-surface defects were detectable by dye penetrant and eddy current methods.

Conclusions:

• A multi-technique NDT approach is essential for comprehensive defect assessment in SLM parts.
• Complementary and redundant information from multiple methods enhances the reliability of integrity evaluation.
• This integrated NDT strategy is vital for advancing AM in critical structural applications.