My Turn
The time has finally come! During my last week at the LPL, I started looking at live data using the FIB Microscope. I did save some data, but it turns out that my personal computer is unable to display most of the OIM images of the maps. I do however have a couple of the live images from the microscope. I analyzed a sample of Nickle in the FIB. In order to do this, I had to learn how to insert the sample into the FIB. Dr. Wallace helped me do this. We started by releasing the vacuum in the FIB. Then we slowly, and carefully opened the door. The sample was secured to a post using double sided copper tape. The post was at a pre-tilt of 52 degrees. Since Electron Backscatter Diffraction requires the sample to be tilted at 70 degrees, we had to manually tell the machine to tilt an extra 18 degrees. Before doing that, we had to close the door. While holding the door, we initiated the pump and waited for a click noise to confirm the door was secure and the machine was pumping out air to create the vacuum.
Here is the FIB that I used to obtain the small bits of data I got. The large flat surface on the right with the cylinder is the door. There are a number of attachment that are on the FIB, the most notable being the EBSD detector.
Unfortunately, the data that I collected was very poor. The sample itself had not been prepared and it contained a number of scratches and dust particles. These things we can see in the images from the microscope.
Above, we can see the dust particles on the surface of the Nickle. Dark squares are also apparent. These squares are areas that we had observed. Since SEMs use electrons to detect surface elements, they also leave a mark.
The black boxes in the darkest square on the image. This was the square that I spent the most time on, hence the square being darker and more apparent than the rest. The blue shows some examples of the dust.
Although I have no images from the OIM software, I have this image from my phone. This is an IQ map from my Ni Sample. Here, we can see the number of scratches that was on the sample. In this upcoming week, I will be working with Prajkta. Prajkta was gone during the last week, so I was unable to work with her. However, Prajkta works closely with the polishing machine. After learning how to polish samples, I will be able to view more samples in better quality.
A sidenote, Dr. Wallace asked me to create a map in OIM that included blue, white and red for a U of A colored image. This was part of a tutorial for OIM, however, they did not use the same colors. The way each grain was associated with a color was using each individual crystal lattice. For a certain crystal orientation, the grain would be given a number value. Viewing an Inverse Pole Figure Chart, we can see which of these orientations have a peak in the number of grains that share each orientation. In the case of this sample, the peak orientations were <111>, <115>, and <437>. Using some settings, we can use a range and associate that range around a peak to a color. While changing the settings to match the U of A color scheme, I also took the liberty to change the colors to match a BASIS Oro Valley Color scheme. Since we are using ranges, we can see a change in the individual colors (from dark purple to lighter purple, darker gray to lighter gray, etc.) Enjoy!
