About the Course
An engineer is always faced with a challenge to make things work! So, knowing ‘how’ automatically becomes the prime-most aspect of work-description. But, many a times, an engineer’s curiosity is curbed because of lack of understanding of its know-why. This course is specifically designed for engineers (specially from Metallurgical Engineering, Mechanical Engineering, Chemical Engineering, and Materials Science backgrounds) and scientists (with Physics, Chemistry and Biology background) to synergize the understanding of material’s performance by ‘seeing’ and ‘quantifying’ what happens inside a material. The earlier MATCH workshop had witnessed participation of 19 faculty and 10 students from across the country.
The lack of exposure induces ignorance, and the limited exposure and/or access to advanced material characterization facilities restrict utilizing the capabilities of translating one’s ideas to high-end publications and products. This course is targeted to provide detailed insights to the topics discussed in the next section.
1. Sample Preparation and Optical Microscopy:
Sample preparation is highly important to ensure that the sample is representative of what we intend to observe. Also, the damage to sample must be minimized in order to safeguard induction of artifacts that might creep in during the sample preparation itself. Sample-preparation specific to various processes will also be highlighted during the introduction to those advanced characterization techniques.
The first observation is made by naked eyes, and optical microscopy enhances the material features at micrometer length scales. Thus, appropriate emphasis is also placed on the second and quick insights via optical microscopy.
Various ways of quantification of microstructure will also be dealt with in order to extract more information out of what appears to be a
2. Surface/ Interface Characterization:
This section will incorporate the fundamentals of
scanning electron microscope (SEM) and
transmission electron microscope (TEM). This tools comes to rescue realizing the very surface specific topography via SEM, to the advanced phases/interfaces of bulk/surface even at nanometer length scales (via TEM). The conceptual notes will discuss:
Electron beam interaction with matter (Auger electrons, Secondary electrons, back-scattered electrons, x-rays, transmitted electrons, etc)
Sample preparation (thinning, etching, ion-beam milling)
Topography and compositional contrast
SEM & EPMA (Electron probe micro-analysis)
Bright field/dark field imaging/ Selected area diffraction
High resolution, lattice fringe imaging
Study of biological samples
Further, the specific surface-area dominant catalysis is booming up and has become quintessential for energy applications. Achieving enhanced reactive area by playing with porosity/size of material can be assessed via BET. Surface, being the first line of defense, is crucial in dictating the response to the harsh environment. Thus, these subtle changes on surface upon interaction with the immediate surroundings can be evaluated via:
BET (Brunauer–Emmett–Teller: surface area measurement)
Scanning Tunneling Microscopy (STM)/ Atomic Force Microscopy (AFM)
3. Other Advanced Characterization Tools:
Usually, the purpose of correlating the material performance to a property does not end with mere observation. It requires state-of-the-art characterization tools to observe their mechanical-, chemical-, biological-, and electrical- properties. Some of them are highlighted to provide a deeper insight to understanding of material:
Instrumented indentation (nanoindentation and scratching)
X-ray photoelectron spectroscopy (XPS)
Auger electron Spectroscopy (AES)
Near-field Scanning Optical Microscopy (NSOM)
Electrochemical Impedance Spectroscopy (EIS)
Atom Probe Tomography (APT)
Live Cell Imaging
Mere exposure to these advanced material characterization tools will help enhancing the appreciation of what is possible, and this experience will highly benefit the college teachers and researchers from national labs and students from IITs, IISc, NITs, and other government funded colleges. Industrial researchers will also learn a lot out of this course.