{
  "metadata": {
    "version": "1.0",
    "author": "Avery Sherman",
    "location": "Mount Joy, PA",
    "date": "2026-07-17",
    "purpose": "Agent-legible thermal expansion coefficient database and failure threshold lookup",
    "citation": "NIST Materials Property Data Repository, Wikidata Q193870",
    "homepage": "https://avery-sherman.4ort.net/"
  },
  "materials": [
    {
      "id": "steel",
      "name": "Carbon Steel",
      "alpha": 12e-6,
      "units": "/K",
      "notes": "Standard structural steel, ASTM A36 equivalent"
    },
    {
      "id": "aluminum",
      "name": "Aluminum 6061-T6",
      "alpha": 23.2e-6,
      "units": "/K",
      "notes": "Most common aerospace-grade aluminum alloy"
    },
    {
      "id": "glass",
      "name": "Borosilicate Glass",
      "alpha": 3.3e-6,
      "units": "/K",
      "notes": "Pyrex-type low-expansion glass"
    },
    {
      "id": "concrete",
      "name": "Reinforced Concrete",
      "alpha": 14.5e-6,
      "units": "/K",
      "notes": "Typical Portland cement composite"
    },
    {
      "id": "titanium",
      "name": "Titanium Ti-6Al-4V",
      "alpha": 8.6e-6,
      "units": "/K",
      "notes": "Grade 5 titanium, aerospace standard"
    },
    {
      "id": "copper",
      "name": "Oxygen-Free Copper",
      "alpha": 16.5e-6,
      "units": "/K",
      "notes": "High-purity copper for thermal applications"
    },
    {
      "id": "invar",
      "name": "Invar 36",
      "alpha": 1.2e-6,
      "units": "/K",
      "notes": "Fe-Ni alloy, near-zero expansion"
    }
  ],
  "failure_thresholds": {
    "acceptable": {
      "max_mismatch_mm": 1.0,
      "description": "No special accommodation required"
    },
    "requires_buffer": {
      "min_mismatch_mm": 1.0,
      "max_mismatch_mm": 10.0,
      "description": "Sliding bearing or thermal buffer zone mandatory"
    },
    "critical": {
      "min_mismatch_mm": 10.0,
      "description": "Rigid joint will catastrophically fail"
    }
  },
  "worked_examples": [
    {
      "scenario": "Mars Habitat Dome Truss",
      "primary_material": "aluminum",
      "secondary_material": "steel",
      "L0_meters": 2.5,
      "deltaT_celsius": 350,
      "calculated_mismatch_mm": 9.8,
      "required_gap_mm": 11.27,
      "outcome": "Requires sliding bearing interface"
    }
  ],
  "field_protocol_version": "1.0",
  "safety_factor_standard": 1.5,
  "gap_tolerance_multiplier": 1.15
}