Introduction to Orientation Imaging Microscopy (OIM), 3-Dimensional FIB/EBSD, Insitu testing facilities, Nano indentation, Combined spectroscopy and microscopy techniques, Temperature related measurement (TG+DTA) and DSC, Thermomechanical physical simulator, Gleeble, Neutron diffraction techniques.

1. Module 4:Advanced Characterization
Techniques
Introduction to Orientation Imaging Microscopy (OIM), 3-Dimensional
FIB/EBSD, Insitu testing facilities, Nano indentation, Combined
spectroscopy and microscopy techniques, Temperature related measurement
(TG+DTA) and DSC, Thermomechanical physical simulator, Gleeble,
Neutron diffraction techniques.

2. What is OIM?
• A technique used to study the crystallographic orientation of grains in
polycrystalline materials.
• Primarily implemented through Electron Backscatter Diffraction (EBSD) in a
Scanning Electron Microscope (SEM).
• Provides 2D or 3D maps of grain structure, orientation, and phase distribution.

4. How OIM Works
• Electron beam interacts with tilted sample → produces
Kikuchi patterns.
• Patterns are indexed to determine crystal orientation.
• Multiple points scanned to create orientation maps.

5. Key Outputs from OIM
• Inverse Pole Figure (IPF) maps
• Grain boundary maps
• Orientation Distribution Functions (ODF)
• Misorientation and strain maps (KAM)

6. Applications of OIM
• Analyzing grain size, texture, and boundary types.
• Studying phase transformations and recrystallization.
• Investigating deformation mechanisms in metals and ceramics.
• Quality control in advanced manufacturing processes.

7. Advantages of OIM
• High spatial resolution (down to ~20 nm).
• Fast data acquisition and automated analysis.
• Can be coupled with EDS for phase and composition mapping.

8. Limitations
• Surface must be flat and well-polished.
• Conductive coating needed for non-conductive samples.
• Resolution limited by SEM and EBSD detector
performance.

9. Recent Developments
• High-speed EBSD for faster mapping.
• In-situ OIM under mechanical or thermal loads.
• Integration with AI and machine learning for automated feature
recognition.

10. 3-Dimensional
FIB/EBSD

11. What is 3D FIB/EBSD?
• Combines Focused Ion Beam (FIB) slicing with Electron
Backscatter Diffraction (EBSD).
• Reconstructs 3D microstructures layer-by-layer.
How It Works:
• FIB mills successive layers of the material.
• EBSD scans after each slice generate orientation maps.
• Data stacked using software to form a 3D model.

12. Applications:
• Study of grain morphology, phase distribution, and triple junctions.
• Analysis of recrystallization and deformation mechanisms.
• Used in additive manufacturing, geology, and metallurgy.
Advantages:
• True 3D microstructural insights.
• High spatial resolution (~50–100 nm).
Limitations:
• Time-consuming and destructive.
• Requires vacuum-compatible, conductive samples.

13. In-situ Testing Facilities
What is In-situ Testing?
• Real-time testing of materials under mechanical, thermal, or environmental stress.
• Performed inside SEM, TEM, X-ray, or neutron facilities.
Key Features:
• Visualizes deformation, crack growth, and phase transformations as they happen.
• Equipped with tensile/compression stages, heating elements, and environmental chambers.
• Often combined with EBSD, DIC, or spectroscopy.

14. Applications:
• Studying fracture mechanics, corrosion, and fatigue behavior.
• Battery research (e.g., electrode expansion).
• Biomedical implants under physiological conditions.
Advantages:
• Links material structure with real-time performance.
• Enables multi-physics testing (thermal, mechanical, electrical).
Limitations:
• Complex setup and calibration.
• Limited to micro-scale samples in many cases.

15. Nanoindentation
What is Nanoindentation?
• Measures mechanical properties (e.g., hardness, modulus) at the nano to micro-
scale.
• Uses a sharp indenter (e.g., Berkovich tip) with precise load-displacement
monitoring.
Working Principle:
• Load applied → indenter penetrates sample.
• Load-displacement curve analyzed (Oliver-Pharr method).
Key Measurements:
• Hardness (H)
• Elastic modulus (E)
• Time-dependent behavior (e.g., creep, viscoelasticity)

17. Applications:
• Thin films, coatings, MEMS devices.
• Biomedical materials (e.g., dental, bone coatings).
• Semiconductor and energy materials.
Advanced Modes:
• High-temperature nanoindentation
• Continuous stiffness measurement (CSM)
• AFM-nanoindentation hybrid systems

18. Advantages:
• High resolution in both force and depth.
• Localized property measurement.
Limitations:
• Sensitive to surface quality.
• Requires calibration and homogeneous test areas.

19. Combined Spectroscopy and Microscopy Techniques
What Are They?
• Integration of spectroscopy (chemical analysis) and microscopy
(spatial/structural analysis).
• Enables correlated chemical, structural, and morphological
characterization at micro to nano scales.
• Commonly used in materials science, nanotechnology, and life sciences.

20. Key Techniques & Combinations
1.SEM + EDS (Energy Dispersive X-ray Spectroscopy)
1. Provides element mapping with microstructure imaging.
2. Widely used in failure analysis and alloy characterization.
2.TEM + EELS (Electron Energy Loss Spectroscopy)
1. Offers atomic-scale imaging and chemical state analysis.
2. Suitable for studying defects, interfaces, and electronic structures.
3.AFM + Raman Spectroscopy
1. Combines topographical imaging with vibrational spectroscopy.
2. Ideal for 2D materials, polymers, and biomaterials.

21. 4.SEM + CL (Cathodoluminescence)
1. Reveals optical/electronic properties along with morphology.
2. Used in semiconductors, geology, and optoelectronics.
5.ToF-SIMS + SEM
3. Combines high-resolution surface imaging and mass spectrometry.
4. Detects chemical species and isotopes at the nanoscale.

22. Applications
• Correlative analysis of structure–property relationships.
• Mapping of chemical composition, phase, and defects.
• Research in semiconductors, biomaterials, nanocomposites, and catalysis.
• Environmental studies (e.g., pollutant analysis on microstructures).
Advantages
• Multimodal datasets from a single sample region.
• High spatial + chemical resolution.
• Saves time and preserves sample integrity.
Limitations
• Instrument complexity and high cost.
• Requires careful alignment and calibration.
• Data interpretation can be challenging due to overlapping signals.

23. Temperature-related Measurements (TG + DTA + DSC)
Thermogravimetric Analysis (TGA)
• Measures mass change of a sample as a function of temperature or time.
• Useful for studying thermal stability, decomposition, and oxidation.
Differential Thermal Analysis (DTA)
• Measures the temperature difference between sample and reference during heating.
• Detects endothermic (e.g., melting) and exothermic (e.g., crystallization) reactions.
Differential Scanning Calorimetry (DSC)
• Measures heat flow into or out of a sample vs. temperature/time.
• Quantifies melting point, glass transition, crystallization, and reaction enthalpies.

24. TGA schematic diagram

25. DSC schematic diagram

26. DTA schematic diagram

27. Applications
• Phase transitions in polymers, metals, ceramics.
• Thermal degradation studies.
• Material quality control.
Advantages
• Precise thermal and mass change data.
• Small sample size; easy sample prep.
Limitations
• Cannot give structural or morphological data.
• Calibration and baseline corrections required.

28. Thermomechanical Physical Simulator
What It Is
• A lab-scale machine to simulate industrial thermo-mechanical processes (e.g., rolling,
forging, welding).
• Applies controlled heating, cooling, and deformation cycles to samples.
Functions
• Simulates real thermal-mechanical history of industrial processes.
• Produces realistic microstructures for study.

29. Features
• Programmable thermal profiles.
• Multi-axis deformation control.
• Real-time data capture (load, strain, temp).
Applications
• Welding simulations, phase transformation studies.
• Formability and heat treatment optimization.
Advantages
• Replicates complex industrial conditions.
• Enables microstructure-performance correlation.

30. Gleeble Thermomechanical Simulator
What is Gleeble?
• A high-precision thermomechanical testing system.
• Simulates industrial processing conditions like hot forming, quenching, and joining.
Capabilities
• Rapid heating/cooling (up to 10,000°C/s).
• Simultaneous mechanical loading (tensile/compressive).
• High-temp testing up to ~3000°C.
Key Applications
• Continuous casting, heat-affected zone (HAZ) simulation.
• Crack sensitivity testing in welds.
• Stress-strain behavior at elevated temps.
Advantages
• Full control of strain rate, temp, and force.
• Realistic simulation of real-world manufacturing.
• Supports metallurgical, mechanical, and failure analysis.

31. Neutron Diffraction Techniques
What is Neutron Diffraction?
• Uses neutron beams to study atomic arrangement and stresses in materials.
• Similar to X-ray diffraction but with deeper penetration.
Key Features
• Non-destructive, bulk material analysis.
• Sensitive to light elements (e.g., hydrogen).
• Can operate under in-situ conditions (temp, stress).
Applications
• Residual stress mapping in components (e.g., railway wheels, turbine blades).
• Crystal structure and texture analysis.
• Phase quantification and kinetics studies.
Advantages
• Deeper penetration than X-rays.
• Accurate internal stress and texture data.
• In-situ studies during heating/cooling or loading.
Limitations
• Requires access to a nuclear reactor or spallation source.
• Long data acquisition time.

32. Neutron Diffraction schematic diagram