Engineers rely on technical data sheets to make informed decisions, by comparing different materials and selecting the best ones. If they are lucky, they have the resources and time to verify the figures by testing their own samples. Unfortunately, the majority just have to trust the published data.
When I worked a Red Bull Racing, I was fortunate enough to have access to the R&D department’s equipment. This allowed me to test lots of different SLS materials and compare them to the datasheets.
I discovered that many suppliers published mechanical test results, were not able to be replicated. There were a few suppliers, however, whose data we were able to get close to matching.
It is reasonably easy to significantly improve the mechanical properties of a 3D Printed test part, even if the ‘test method’ is the same standard. You could make the improvements by running with 100% virgin material, placing the test part in the centre (optimum) position of the build, increasing the energy going into the part and then polish the part at the end to remove and build lines or defects. This would give a ‘best case scenario’ for the published figures, and the figures would look amazing.
However, in practice, a part would never be made this way. MJF and SLS powder is always recycled and blended (how much depends if a company’s priority is on cost saving or quality). Too much energy will make the parts inaccurate with poor detail. And a machine will always be full of different components that are built in all different areas of the build.
For these reasons, at Graphite Additive Manufacturing, I decided to publish ‘real world’ data of our SinterWorx SLS materials. We build mechanical test parts on regular builds, with standard parameters, and alongside our client’s components. Our clients have also verified our published data.
Our published data will not be the most impressive on the market. However, I can be sure that the parts we produce will regularly exceed our clients’ expectations. I are confident that our SinterWorx SLS materials, and the parts we produce, are some of the highest performing on the market.