Jason Burbey

Purdue University

Project Title: Transmission Electron Microscope Investigation of Rolled Nanoscale Multilayers
Advisor: Prof. Eric Stach

Introduction

In the recent past a renewed interest of laminated metallic composites has been developed hoping to use these laminates in industrial applications. Professor Ravichandran of the Metallurical Engineering Dept. requested that transmission electron microscope (TEM) analysis be done on the metallic laminates he had created by means of repeated cold rolling. These laminates are made of AISI 1010 steel and CDA 260 brass (Cu-30 wt.% Zn). We are interested in the microstructure to find out if nanoscale grains were achieved as described in his article and to observe the dislocation density/distribution to characterize the properties of the laminates. These observations will help us to develop an understanding of the mechanism responsible for the increase in yield strength found during Ravichandran's study.

Project Objectives

Develop accurate and efficient way to prepare specimens for TEM analysis Use bright field imaging to acquire images of the microstructure

Approach

Thin disk specimens to 10-15 microns using the Model 2000 Sample Prep System, a.k.a. The Dimpler Make specimens electron transparent using the Ion Mill Take bright-field images in the TEM for characterization

Findings

One of the biggest lessons you learn during research is that not everything can go as smoothly as planned. This summer I was able to become efficient in using the dimpler to successfully produce several specimens of the metallic laminates for Professor Ravichandran and other materials. The Ion Mill was out of order for a majority of the summer, so no specimens have been made yet to be characterized in the TEM. I am glad to say that I learned a lot this summer about TEM sample preparation and that I will be continuing this research during the academic year.

Fig 1. The Model 2000 Sample Prep System used to initially thin the metallic laminates to between 10 and 15 microns.
Fig 2: The JEOL Model 2000FX TEM that will be used to make a microstructural characterization of the metallic laminates.

Contact me: jburbey@purdue.edu