The huge variety of materials characterisation methods and their diverse terminologies and descriptions have been the subject of a pre-standard (CWA 17815) [1] aiming to provide a unified documentation including description of workflows, known as CHADA. While this type of documentation was a big step forward, it lacks machine readability and interoperability. To capture and exchange information about characterisation workflows, there is the need for a visual and machine readable representation supporting an unambiguous interpretation of the knowledge about characterisation methods and workflows.

We present a framework for describing characterisation workflows both at visual and semantic level. For a detailed and well defined representation of characterisation workflows, the BPMN 2.0 is used, having both a rich visual notation and an XML serialisation format, thus facilitating the exchange of diagrams between operators. The semantics of the characterisation workflows is modelled through an ontology. In the NanoMECommons project [2], the EMMO-based CHAracterisation MEthodology Ontology (CHAMEO) [3,4] has been developed on the basis of CHADA in order to model methodological aspects of a characterisation process that are in common across different characterisation methods. It is used as a basis for characterisation technique-specific ontologies. CHAMEO has been enriched with the constructs allowing the breakdown of a workflow into specific tasks or sub-workflows. This framework has been used to represent workflows of nano-mechanical characterisation methods (e.g. Nanoindentation, FIB-DIC), detailing the specific aspects of their workflows and related taxonomies, for example the specific calibration procedures, the types of nanoindentor tips and data post-processing methods. Furthermore, the approach has been extended to complex industrial application cases involving multiple techniques, e.g. the characterisation of multi-layered automotive coatings.  For each of the characterisation workflows and industrial use-cases a BPMN diagram and a CHAMEO-based ontology has been developed, supporting clear documentation, harmonisation and interoperability of characterisation workflows.

Acknowlewdgement:
This work has been supported by the European Union under the HORIZON2020 Framework Programme Grant Agreement no. 952869 (NanoMECommons)

References
[1] Materials characterisation - Terminology, metadata and classification, CEN Workshop Agreement, CWA 17815, 2021 https://www.cencenelec.eu/media/CEN-CENELEC/CWAs/ICT/cwa17815.pdf
[2] https://www.nanomecommons.net/   
[3] Characterisation Methodology Ontology (CHAMEO); https://github.com/emmo-repo/domain-characterisation-methodology
[4] P. Del Nostro; G. Goldbeck; D. Toti, Applied Ontology, CHAMEO: An Ontology for the Harmonisation of Materials Characterisation Methodologies, 2022, 17, 401-421.