• Question: Whats it like looking at deformed samples

    Asked by matthew7421 to Andy on 17 Jun 2011.
    • Photo: Andy Norton

      Andy Norton answered on 17 Jun 2011:

      Heya matthew7421.

      That’s a really good question. It’s really interesting looking at the samples that I have compressed. Once I’ve compressed a sample, I then grind and polish it down so that it is really thin (around a tenth of a millimetre across!) and then can put it in my microscope (there is a picture of the microscope on my profile – I would post it in this answer but I don’t think that I can!). I am looking for a number of things in my samples. Firstly, I want to see if there are any cracks. Sometimes there are lots of crack cracks (a few microns along, and a micron is a 1/1000 of a millimetre), and it is interesting to see what these look like. I am also looking for things called deformation twins. This is when the atoms are rearranged because of the stress. They form long thin bands (there is a photo on my profile – have you seen it?). There might also be things called dislocations, which is another way that the atoms can rearrange because of the stress. I then look at these things in my deformed samples, and can compare the amount/type of these with different samples.

      Does that explain it ok?

Comments

  • Photo: matthew7421

    matthew7421 commented on :

    What kind of things besides cracks are you looking for in your samples?

    • Photo: Andy

      Andy commented on :

      Hey matthew,

      Sorry I didn’t reply to your comment before – I didn’t get an email telling me about it! We can look for things called dislocations or deformation twins (which is when the atoms in the sample rearrange themselves because of the stress – it is interesting to compare the amount of types of these things from sample to sample). We can also look to see if there are any pores of any sort (like a hole in the sample) which might change how the sample fails. Have you seen the image of a twin that I put on my profile? That’s the sort of thing that I see with the microscope 🙂

  • Photo: Barbara

    Barbara commented on :

    Matthew7421 you are asking really great questions. Well done! Do you want to be a scientist because I think you would be awesome.