🤖 AI Summary
This study addresses three critical challenges in materials science ontologies: fragmentation, insufficient regulatory integration, and a lack of mechanistic explanatory power. To overcome these limitations, the authors propose a novel multi-level modular ontology architecture featuring a three-dimensional design that integrates abstraction level, user audience, and mechanistic depth. The framework incorporates a seven-layer mechanistic explanation backbone grounded in symmetry, thermodynamics, defect chemistry, and related principles. Implemented using OWL and SHACL, the resulting Ceramic Ontology (OCO v0.94) comprises 5,196 classes, 167,348 axioms, 829 cross-ontology mappings, and 163 competency questions. This ontology enables cross-material reuse, supports deep mechanistic reasoning, and facilitates compliance with the European Union’s Digital Product Passport requirements.
📝 Abstract
The Materials Science and Engineering ontology landscape is fragmented along multiple axes simultaneously. Horizontally: a recent survey identified 94 ontologies of which over 40 are structurally incompatible; each new application domain -- ceramics, polymers, batteries, smart materials -- typically restarts ontology design from scratch. Vertically: EU regulation (CSRD, CSDDD, PPWR, CBAM, R2R, AI Act, ESPR) forces material, manufacturing, supply-chain, and lifecycle data into integrated digital product passports, leaving ontologies that only address horizontal fragmentation incomplete for any contemporary consumer. And mechanistically: a vocabulary that records that BNT-BT has $d_{33} \approx 580$ pC/N stores a fact but cannot surface why -- Bi-6s$^2$ lone-pair stereo-activity, anomalous Born effective charges, soft modes, defect chemistry -- without a systematic explanation skeleton. We propose a multi-level modular architecture with two independent classification axes -- level of abstraction (L0 bridges, L1 material-agnostic laboratory-notebook, L2 material-class-specific, L3 categorical reasoning) and consumer audience (material vs. compliance) -- in which the material-specific level is internally organised by a seven-tier mechanistic-explanation skeleton (Symmetry, Energy/DFT, Thermo/CALPHAD, Kinetics, Microstructure, Defect chemistry, Bonding) applicable to any crystalline ionic oxide. The level-and-audience modularity dissolves the horizontal fragmentation, the compliance audience absorbs the vertical regulation pressure, and the seven-tier organisation of Level 2 delivers the mechanistic explanation depth. We instantiate the architecture as the OntoCrafter Ceramics Ontology (OCO v0.94): 5,196 classes across 44 modules; 167,348 OWL axioms (40,454 logical); 1,674 properties; 829 cross-ontology bridge mappings; 1,172 SHACL shapes; 163 published competency questions.