Test Specimen for Strength Testing of Additive Manufactured Ceramics by the VPP Process: the CharAM-Specimen

The strength of additively manufactured ceramics may depend on the orientation of the direction in which tensile stresses act during testing with respect to the building direction (z). This may be due to

─ specific properties of the interfaces between the deposited layers
─ aliasing effects on surfaces
─ others

In order to address this characteristic behaviour together with other aspects relevant to ceramics and the additive manufacturing process, we aim at:

─ providing a test piece geometry with dimensions relevant to a specific ceramic AM method that can be manufactured in different orientations with respect to the building direction z.
─ providing 30+ individual test pieces for a statistical strength analysis produced in a time-efficient single print job
─ providing test pieces with prospective tensile loaded faces that are neither the faces attached to the building platform during manufacturing nor the last printed layer
─ providing test pieces with prospective tensile loaded faces that are not in contact with kiln furniture during thermal processing

A test specimen suitable for strength testing of additively manufactured ceramics is presented. A specimen consists of 48 test pieces in the form of carefully designed constant-moment cantilever beams which are attached to a baseplate. The baseplate is formed by two connected solid plates with a specified angle (ꞵ) in between. By variation of this angle, different orientations of the cantilever axis (prospective tension-loaded face) with respect to the building direction of the AM process can be achieved. *.stl files for specimens with three different orientations/configurations are provided.
Strength testing is performed by loading each cantilever at a pre-defined loading point (A) to failure.
A description of the testing method as well as a detailed error analysis is provided in https://doi.org/10.1016/j.oceram.2023.100410
An example of how this specimen can be used to evaluate the strength of LCM ceramics can be found in https://doi.org/10.1016/j.oceram.2024.100557