Material properties of copper

The comic shows two men that are testing how hard they can pull on both sides of a 3D printed copper stick before it breaks. This comic strip was chosen because in my master thesis I wanted to test under which traction a 3D printed copper stick would break. It is important to know the material properties e.g., for building electronic parts.

Simplified Abstract

For selective laser beam melting (a form of socalled 3D printing) the mechanical properties of printed components for pure copper are not known so far. However, through tensile teststhe determination of tensile strength and elongation behavior of copper is possible. Therefore, the goal of my master Thesis was i) to find suitable combinations of parameters to produce standardized 3D printed copper sticks which could be used in tension tests and ii) to determine the traction force at which the copper stick would break. First, the tensile samples had to meet certain requirements such as an optimal shape and density to obtain meaningful
results. For example, the density had to reach a minimum value of 99.5% which means that the copper stick had to be of 99.5% pure copper. Furthermore, the copper sticks had to be homogenous without any air inclusions and be free from visible flaws.
To achieve my goals, I printed the copper samples with a 3D machine which turned out to be the real difficulty within my master Thesis. Under the given conditions it was almost impossible to produce good samples. Hence, I wasn ́t able to complete the first step and unfortunately couldn ́t measure the tension needed to break my samples. Research is not always easy and sometimes you have to take one step back. In my case this means that still a lot of research must be conducted on 3D printing of pure copper before using 3D printed copper in electronics or other industrial products.

 

Name:                        Matthias Harr