This is the third installment of our blog series on Material Development for EBM: Ferrium C64. For those who have not read the first two posts, they can be found at the following links: Part 1, Part 2. Following the development of the melt theme for Ferrium C64, the next step was to begin evaluating the properties of the EBM material.
As the process parameters became more stable and the melt theme produced visually acceptable material (minimal sparking, no visible porosity, no swelling) it was time to begin evaluating the underlying microstructure and mechanical properties of the material. The first material characteristic we evaluated was density. To estimate density, sample cubes produced in early supported builds were polished and etched. Figure 1 is an example of the size of the cubes used.
The surfaces of these samples were viewed under a microscope and digital images were captured for analysis. Using ImageJ software and these digital images, porosity was estimated for each cutup sample. Figure 2 shows two images of the polished cutup sample surfaces. The first image (left) is from an earlier DOE trial, exhibiting more internal porosity (bright spots in the image). This sample had an estimated density of 98.5%. The second image (right) is from a later trial where the parameters were adjusted to produce a denser melt. This sample had an estimated density of 99.6%.
We will continue our analysis of EBM Ferrium C64 by evaluating the following material properties:
- Tensile and Yield Strength
- Chemistry of melted material and recycled powder
- Affects of carburization
- Gear tooth bending strength
If you are interested in seeing the results of this testing please notify us at email@example.com.