ENN531 Advanced Materials and Engineering Applications

Question:

Electron Backscatter Diffraction (EBSD) is a highly automated process to determine the crystallography of solid materials^[4] (rocks, ice, metals) in the scanning electron microscope.

Experimental

The demonstrator will operate the SEM to demonstrate how EBSD patterns are collected and capture an EBSD map for a stainless steel material. You will be presented with the Euler maps, pole figure and inverse pole figure for the mapped area.

Report

1. Detail the equipment used, and the operating parameters.

2. Measure the grain size from the EBSD pattern, and describe the process for doing so. Using the Hall-Petch equation determine the yield strength of the stainless steel, using the following parameters:

σ₀ = 120 MPa

k_y = 0.54 MPa.m^1/2

3. What would the yield stress be if the grain size could be reduced to 100nm?

4. How would you describe the grain structure of the material (equiaxed, elongated, etc?). Is there a preferred orientation or texture to the sample?

Report

 Your assignment will be to:

1. Detail the equipment used, and the operating parameters in each case. Note that this may vary between groups depending on equipment availability.

2. Present the results for each material, drawing comparison between the samples.

3. Interpret the results to the extent possible, in particular determining:

a. Single or multiwall structure

b. Tube diameter

c. Degree of uniformity (qualitative or otherwise)