The verification of the mechanical properties of binder jetting manufactured parts by instrumented indentation testing

In order to figure out the mechanical properties of freeform bio-medical parts made by Additive Manufacturing (AM), Instrumented Indentation Testing (IIT) is introduced to measure the Young's modulus from the free surface of the parts. The research also conducted several other different methodologies alongside the IIT in measuring the effective Young's modulus as a comparison. A special designed testing machine Mach-1^TM is used conducting the IIT, 3-point bending and compression test. The traditional compression test on standard cylinder parts made from the same binder jetting machine are used as a benchmark of the test material. Three different unit structures with different relative densities are considered, the solid part, the part with 1.0 mm size of grid lattice and the part with 1.5 mm size of grid lattice. Compared with the benchmark results obtained from traditional testing machines and the 3-point bending, the IIT bears a 15% error measuring solid and lattice freeform samples. Through the primary results, the porosity of the material as well as the stylus size and the lattice size contribute largely to the error.