Relevance of Manufacturing-Induced Residual Stress States in Fiber Metal Laminates for Structural Health Monitoring / by Johannes Wiedemann.

Format:

Book

Author/Creator:

Wiedemann, Johannes.

Series:

Mechanics and Adaptronics, 2731-622X

Language:

English

Subjects (All):

Materials.

Materials--Fatigue.

Materials science.

Materials Engineering.

Materials Fatigue.

Materials Science.

Local Subjects:

Materials Engineering.

Materials Fatigue.

Materials Science.

Physical Description:

1 online resource (157 pages)

Edition:

1st ed. 2026.

Place of Publication:

Cham : Springer Nature Switzerland : Imprint: Springer, 2026.

Summary:

This open access dissertation investigates how manufacturing-induced residual stresses in fiber metal laminates (FMLs) affect structural health monitoring (SHM) systems. SHM using guided ultrasonic waves (GUWs) enables internal damage detection and suits FMLs due to their complex damage characteristics. Experimental methods are developed to quantify residual stresses, including sensor-based strain measurements during manufacturing. These validate modified cure cycles aimed at influencing stress states in FMLs consisting of carbon-fiber-reinforced polymer and steel. A simplified method based on the stress-free temperature from asymmetrical reference laminates complements these measurements. The measured residual stresses enable studying their effect on GUW propagation. Dispersion diagrams obtained via laser-scanning vibrometry show no significant influence of residual stress on the phase velocity of fundamental GUW modes. In contrast, external tensile prestress increases wave velocity, highlighting the need to account for such loads in SHM. Fatigue tests show that reducing residual stresses through modified cure cycles delays crack initiation and slows propagation, improving fatigue life. Two key conclusions follow: First, while residual stresses have little effect on wave speed, external loads do and must be considered in SHM. Second, knowing the residual stress state enhances remaining service life predictions after damage detection. These findings advance SHM technology for FMLs by linking residual stress to SHM-relevant parameters. The Author Johannes Wiedemann is recognized for his expertise in structural health monitoring and composite manufacturing, as evidenced by numerous peer-reviewed publications. His collaboration with leading research institutions worldwide deepened his proficiency in these fields.

Contents:

Motivation

Material Characteristics and Structural Health Monitoring of Fiber Metal Laminates

Materials and Manufacturing

Residual Stress Quantification Using Strain Gages

Residual Stress Quantification Using Asymmetric Laminates

Residual Stress Influence on Gueided Ultrasonic Wave Propagation

Residual Stress Influence on Fatigue Life

Conclusion and Outlook.

ISBN:

3-032-09925-0

9783032099259