Residual Properties in Damaged Laminated Composites through Nondestructive Testing: A Review

Area of Science:

• Materials Science
• Mechanical Engineering
• Aerospace Engineering

Background:

• Composite materials present unique challenges for damage tolerance due to their nonhomogeneous nature and multiple failure mechanisms.
• Traditional strength degradation approaches used for metals are not directly applicable to composites, complicating the assessment of residual strength.
• The widespread application of composites necessitates robust damage tolerance strategies, integrating material behavior with reliable inspection methods.

Purpose of the Study:

• To review and analyze various nondestructive techniques (NDTs) for assessing damage in laminated composite structures.
• To evaluate the damage indexes derived from different NDTs and their correlation with residual mechanical performance.
• To provide insights into the significance of NDTs for quantifying damage severity and guiding future research in composite damage tolerance.

Main Methods:

• Literature review of established and emerging nondestructive techniques for composite materials.
• Analysis of the working principles of each NDT to understand how damage is detected and quantified.
• Correlation of damage indexes obtained from NDTs with the material's residual mechanical properties.

Main Results:

• Various NDTs offer quantitative descriptions of the material state, moving beyond simple damage extension.
• The significance of damage indexes varies depending on the NDT's underlying principle and the specific failure mechanisms in composites.
• A clear link between NDT-derived damage quantification and residual performance is crucial for effective damage tolerance.

Conclusions:

• Nondestructive techniques are essential for characterizing damage in composites, enabling better damage tolerance assessments.
• Understanding the relationship between NDT outputs and residual mechanical performance is key to advancing composite design.
• This review provides a framework for selecting and developing NDTs to improve the reliability and application of composite structures.