A Multiscale Material Testing System for In Situ Optical and Electron Microscopes and Its Application.

Area of Science:

• Materials Science
• Mechanical Engineering
• Nanotechnology

Background:

• Accurate mechanical characterization of materials across multiple length scales is crucial for understanding their behavior.
• Existing testing systems often lack the versatility to test materials from the microscale down to the nanoscale.
• In-situ testing within microscopes offers advantages for observing deformation mechanisms.

Purpose of the Study:

• To develop and present a novel hierarchical material testing system (MTS) for in-situ mechanical characterization.
• To enable the measurement of mechanical properties of multiscale materials using optical microscopes (OMs) and scanning electron microscopes (SEMs).
• To demonstrate the system's capability across a wide range of material dimensions and load capacities.

Main Methods:

• The MTS comprises a microscale material testing module (m-MTM) and a nanoscale material testing module (n-MTM).
• The m-MTM utilizes piezoelectric motors and stacks for coarse and fine testing, offering high resolution displacement.
• The n-MTM is fabricated using microelectromechanical system (MEMS) technology for testing at the nanoscale.

Main Results:

• The MTS successfully characterizes materials with lengths from millimeters to tens of nanometers.
• Load capacity ranges from several hundred micronewtons down to several nanonewtons.
• In-situ OM and SEM tests validated the system's performance on carbon fibers, metallic microwires, and bacterial filaments.

Conclusions:

• The developed MTS provides a powerful tool for in-situ mechanical characterization of multiscale materials.
• The hierarchical design allows for precise measurements across a broad spectrum of material sizes and loads.
• This system opens new avenues for investigating material behavior at the micro and nanoscale.