I’ve been working with copper over the last couple of months and there is one object in particular – a dodecahedron – that had required a long process. As I’ve been going along with the creation of the object I’ve discovered that I really enjoy some of the forms it takes along the way. In order to create the object it is first cut by hand from a flat sheet, then it is scored by hand to allow folding. In between each step the metal becomes hardened and brittle and requires annealing where the metal is heated almost to metalling point and then cooled allowing the composition of the metal to return to it’s more malleable ‘pre worked’ condition. In these steps between being a flat sheet and being a three dimensional object it has gone through stages of folding and unfolding which I really enjoyed and felt were objects in their own right expressing the process of the making. Object opened up after testing fit of sides and edges. Annealed and polished copper. Object partially folded without soldering and with side that came loose from a deep score mark. Annealed but unpolished copper.
There is something about the bendiness and fluidity of the unfolded object that makes it look like it’s moving or creeping. It’s also hard to tell if it is metal or metallic paper.
I think there might be something for me in the annealing process itself; the way the physical structure and chemical properties of the metal are actually changed by heat to make it more malleable. Through working (e.g. bending, forming, stretching), the atoms in the metal become ‘dislocated’ which is an irregularity in the crystal structure of the lattice forming the metal. Annealing diffuses the atoms and returns them to their un-dislocated state. There are three parts to the process: recovery, recrystallisation and grain growth. These stages are pretty much what you would expect and you want to avoid the third stage as it can weaken the metal. Getting the metal to the recovery or recrystallisation stage returns it to its workable form. I think that there is something there that I can work with, just not sure quite what will come out of it yet.