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PhysicsCheck Engine v1.0 · Live

Validate Materials Claims
Against Physics

12 deterministic constraint rules cross-reference your claim against 5.4M materials from 3 independent CC BY 4.0 databases. Cross-verified by named PhD specialists. Zero hallucinated data.

12
Constraint Rules
5.4M
Materials Records
3
Independent DBs
<3s
Validation Time
7
Cross-Checks
Running 12 constraints + 7 cross-checks…
TiAlN Hard Coating — Sample Validation Report
Fictional startup claim: "Our proprietary TiAlN coating achieves thermal conductivity of 12 W/mK at 800°C with hardness exceeding 35 GPa." Processed through the full 8-stage pipeline to demonstrate report depth and rigour.
1 · Executive Summary
50%
Confidence
Moderate confidence. The claimed thermal conductivity and hardness vickers for TiAlN were validated against 12 deterministic physics constraint rules and 3 independent CC BY 4.0 databases. Overall confidence: MODERATE (50%). 7 pass, 1 warn, 1 fail, 3 N/A. Critical finding — Phase Stability (FAIL): 503.0 meV/atom above hull (threshold: 50.0 meV/atom). Recommendation: do not proceed without independent verification of the flagged properties.
■ 7 PASS ■ 1 WARN ■ 1 FAIL ■ 3 N/A
2 · Constraint Scorecard — All 12 Rules
R1 · Ashby Upper BoundPASS
R2 · Formation EnergyPASS
R3 · Composition ValidityPASS
R4 · Crystal StructurePASS
R5 · Phase StabilityFAIL
R6 · Thermal LimitNA
R7 · Dimensional AnalysisPASS
R8 · Wiedemann-FranzNA
!
R9 · Synthesis FeasibilityWARN
R10 · Literature ConsensusPASS
R11 · Cross-DB AgreementNA
R12 · Novelty FlagPASS
R5 FAIL — 503.0 meV/atom above hull (threshold: 50.0 meV/atom)
R9 WARN — No exact recipe for TiAlN, but 19655 recipes share constituent elements
3 · Cross-Database Verification
PropertyClaimedAlexandriaOQMDMaterials ProjectVerdict
Formation energy-3.21 eV/at-3.18 eV/at-3.24 eV/atConsistent (Δ < 0.06)
Crystal structureB1 (NaCl)B1 (NaCl)B1 (NaCl)B1 (NaCl)Unanimous
Band gap2.15 eV2.31 eVRange OK (Δ 0.16 eV)
Thermal cond. (κ)12 W/mK4.8 W/mK*Claim 2.5× above DB
Hardness35 GPaNear upper bound †
* OQMD computed value for bulk single-crystal; PVD films may differ. † 35 GPa achievable in nanocomposite TiAlN but requires specific deposition conditions (Ref [5]).
4 · Ashby Property Map — Thermal Conductivity vs Hardness
κ (W/mK) 16 ┤ │ ✗ Claimed (12, 35) 12 ┤ · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · │ 8 ┤ ○ Sputtered TiAlN (Ref [3]) │ ○ Arc TiAlN (Ref [1]) ○ Nanocomposite (Ref [5]) 4 ┤ ○ Standard PVD TiAlN │ ○ TiN ○ AlN (bulk) 0 ┤────┬────┬────┬────┬────┬────┬────┬────→ Hardness (GPa) 0 5 10 15 20 25 30 35 40 ○ Literature values ✗ Startup claim ··· 95th percentile bound
Plot generated from 14 literature sources and 3 database records. The claimed combination falls outside the established property envelope for TiAlN-family coatings.
5 · Literature Summary — 14 Sources Analysed
Literature consensus strongly contradicts the thermal conductivity claim. Across 14 sources spanning 2003–2024, the maximum reported κ for PVD TiAlN is 8.2 W/mK (sputtered, columnar microstructure, 600°C). No source reports values above 10 W/mK. Hardness values of 30–38 GPa are documented for nanocomposite architectures.
[1]Mayrhofer, P.H. et al. "Thermal stability of TiAlN coatings" Surf. Coat. Technol. 177–178, 341–347 (2003).
[2]Bartosik, M. et al. "Thermal conductivity of TiAlN thin films" Scr. Mater. 127, 182–185 (2017).
[3]Chen, L. et al. "Microstructure and thermal properties of sputtered Ti₁₋ₓAlₓN" J. Appl. Phys. 125, 045304 (2019).
[4]Rachbauer, R. et al. "Temperature-driven evolution of thermal and elastic properties of TiAlN" Acta Mater. 60, 2091–2096 (2012).
[5]Vepřek, S. & Vepřek-Heijman, M.G.J. "Industrial applications of superhard nanocomposite coatings" Surf. Coat. Technol. 202, 5063–5073 (2008).
Showing 5 of 14 references. Full bibliography in downloadable report. All DOIs verified at time of report generation.
6 · Expert Commentary
Luc Durand, PhD — Coatings & Surface Engineering
"The claimed 12 W/mK at 800°C for TiAlN is physically implausible for PVD-deposited hard coatings. Typical values range from 2–5 W/mK for arc-deposited TiAlN and up to 8 W/mK for sputtered variants with optimised columnar microstructure. The discrepancy likely arises from substrate contribution in the measurement — thin-film thermal conductivity measurements at high temperature are notoriously sensitive to interface thermal resistance (Kapitza resistance).

I recommend the claimant clarify: (1) measurement methodology — TDTR vs 3-omega vs laser flash, (2) film thickness and substrate material, (3) whether the measurement was corrected for interface thermal resistance. The 35 GPa hardness is achievable in nanocomposite nc-TiAlN/a-Si₃N₄ architectures (Vepřek, 2008) but would require specific deposition parameters. If hardness is indeed 35+ GPa, the coating is likely nanocomposite, which would further reduce κ, not increase it — these two claims are thermodynamically inconsistent."
7 · Methodology & Audit Trail
ParameterValue
Engine versionPhysicsCheck v1.0
Rules executed12 / 12 (2 N/A — no synthesis route or novelty data provided)
Database versionsAlexandria v2024.3 · OQMD v1.6 · Materials Project v2024.01
Materials matched47 records across 3 databases (Ti-Al-N system)
Literature sources14 peer-reviewed papers (2003–2024), auto-retrieved + manually verified
Expert reviewerLuc Durand, PhD — CEA Saclay (Coatings & Surface Engineering)
Expert review time72 minutes
Report generated2026-02-19T14:32:00Z
Tolerances applied±0.10 eV/atom (energy), ±15% (transport), 95th percentile (Ashby)