Hi all; Hope it's the right place to post this, so I am missing a report from the classes I was absent from and I can't find help anywhere.... Here's the result of the experiment: http://img300.imageshack.us/img300/5452/plasticdeformationjx8.jpg [Broken] These are thin pieces of aluminium that had been previously stretched to reach certain lengths (from shortest to longest). Basically this is all I know. I also know that they were put into an oven or furnace for some time (a bit more than 60 minutes), then they were washed in some liquid (chemical substance?), and the result was something like what you can see in the picture. The more stretched a sample was, the smaller grains we can see. So, could someone name the processes that should take place while carrying out such an experiment? Or maybe someone could post an extensive description of a similar experiment? Help will be greatly appreciated. I'm in a tight corner now, so I am clutching at a straw. Many thanks.