{
  "spore": "profile",
  "id": "steel-a36",
  "spore_version": "0.2",
  "family": "carbon-and-alloy-steels",
  "name": "ASTM A36 structural carbon steel",
  "abbreviation": "A36 (UNS K02600)",
  "role": "structural steel",
  "category": "metals",
  "type": "steels-and-stainless",
  "summary": "ASTM A36 is the common low-carbon structural steel of the United States. It is iron with at most 0.26 percent carbon, 1.03 percent manganese and small amounts of silicon, phosphorus, sulfur and copper. Plate under 8 in thick has a minimum yield strength of 36 ksi (250 MPa) and a tensile strength of 58 to 80 ksi (400 to 550 MPa). It is readily welded and bolted, and it is sold as plate, bars, shapes and girders. Unprotected, it rusts in ordinary outdoor air, so it is normally painted or galvanized.\n",
  "best_for": "Welded and bolted structural frames, girders and shapes that will be painted or galvanized",
  "weakest_at": "Rusts outdoors and corrodes first when it touches copper or tin in a wet electrolyte; minimum strength falls above 650 °F (343 °C)",
  "identity": {
    "formula": "Fe balance; C 0.26, Si 0.40, Mn 1.03, P 0.04, S 0.05, Cu 0.20 maximum (wt%, shapes; Wikipedia table, Fe 98.0 as printed). Flanges over 3 in need Mn 0.85 to 1.35 and Si 0.15 to 0.40",
    "designations": [
      {
        "system": "UNS",
        "code": "K02600",
        "source": "wiki-a36",
        "where": "Lead section, sentence on the A36 (UNS K02600) standard"
      },
      {
        "system": "ASTM",
        "code": "A36",
        "source": "ssab-a36",
        "where": "Page title and first product paragraph (ASTM A36 specification)"
      }
    ],
    "source": "wiki-a36",
    "where": "Chemical composition table for shapes and the note below it (Wikipedia, A36 steel)"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "structures"
    ]
  },
  "properties": [
    {
      "benchmark": "yield_strength",
      "label": "Minimum yield strength, mill plate 0.100 to 6.00 in (SSAB datasheet)",
      "value": 36,
      "bound": "lower",
      "unit": "ksi",
      "scope": "material",
      "conditions": {
        "form": "mill plate and temper-leveled plate (SSAB product table)",
        "thickness": "0.100 to 6.00 in (2.54 to 152 mm)",
        "test": "transverse tension test per ASTM A6, as printed by SSAB",
        "basis": "minimum as printed in the SSAB ASTM A36 mechanical properties table"
      },
      "method": "Mechanical properties table, minimum value as printed",
      "status": "ground",
      "source": "ssab-a36",
      "where": "Mechanical Properties table, Yield strength (min ksi) row",
      "source_detail": {
        "title": "SSAB: ASTM A36 structural steel product page",
        "id": "ASTM A36 (SSAB)",
        "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
        "year": 2026,
        "kind": "datasheet",
        "license": "SSAB website (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Minimum yield strength, plates, bars and shapes under 8 in (Wikipedia)",
      "value": 250,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "plates, bars and shapes",
        "thickness": "less than 8 in (203 mm)",
        "basis": "minimum as printed with its MPa conversion; the article cites the Steel Construction Manual"
      },
      "method": "Properties section, minimum value as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, first paragraph (minimum yield strength)",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Minimum yield strength, plates over 8 in thick (Wikipedia)",
      "value": 220,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "plates",
        "thickness": "more than 8 in (203 mm)",
        "basis": "Wikipedia prints 32 ksi (220 MPa) for plates thicker than 8 inches"
      },
      "method": "Properties section, minimum value as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, first paragraph (plates thicker than 8 inches)",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength range, mill plate 0.100 to 6.00 in (SSAB datasheet)",
      "value": 58,
      "value_high": 80,
      "bound": "range",
      "unit": "ksi",
      "scope": "material",
      "conditions": {
        "form": "mill plate and temper-leveled plate (SSAB product table)",
        "thickness": "0.100 to 6.00 in (2.54 to 152 mm)",
        "test": "transverse tension test per ASTM A6, as printed by SSAB",
        "basis": "specified range as printed (58 minimum, 80 maximum)"
      },
      "method": "Mechanical properties table, minimum and maximum as printed",
      "status": "ground",
      "source": "ssab-a36",
      "where": "Mechanical Properties table, Tensile strength row",
      "source_detail": {
        "title": "SSAB: ASTM A36 structural steel product page",
        "id": "ASTM A36 (SSAB)",
        "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
        "year": 2026,
        "kind": "datasheet",
        "license": "SSAB website (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength range, plates, bars and shapes (Wikipedia)",
      "value": 400,
      "value_high": 550,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "plates, bars and shapes",
        "thickness": "less than 8 in (203 mm); plates over 8 in carry the same range",
        "basis": "Wikipedia prints 58 to 80 ksi (400 to 550 MPa)"
      },
      "method": "Properties section, range as printed with its MPa conversion",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, first paragraph (ultimate tensile strength)",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Minimum ultimate strength at 700 °F (Wikipedia)",
      "value": 370,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "bars and shapes",
        "thickness": "not stated",
        "temperature": "700 °F (371 °C)",
        "basis": "above 650 °F (343 °C) the minimum falls from 58 ksi (400 MPa); Wikipedia prints 54 ksi (370 MPa) at 700 °F (371 °C)"
      },
      "method": "Properties section, minimum strength at temperature as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, sentence on bars and shapes above 650 °F",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Minimum ultimate strength at 800 °F (Wikipedia)",
      "value": 260,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "bars and shapes",
        "thickness": "not stated",
        "temperature": "800 °F (427 °C)",
        "basis": "Wikipedia prints 37 ksi (260 MPa) at 800 °F (427 °C)"
      },
      "method": "Properties section, minimum strength at temperature as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, sentence on bars and shapes above 650 °F",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Minimum elongation in 2 in, mill plate (SSAB datasheet)",
      "value": 21,
      "bound": "lower",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "mill plate and temper-leveled plate (SSAB product table)",
        "thickness": "0.100 to 6.00 in (2.54 to 152 mm)",
        "gauge": "2 in",
        "basis": "SSAB footnote: for plates wider than 24 in the requirement is reduced by two percentage points"
      },
      "method": "Mechanical properties table, minimum as printed",
      "status": "ground",
      "source": "ssab-a36",
      "where": "Mechanical Properties table, Elongation in 2 in (min %) row",
      "source_detail": {
        "title": "SSAB: ASTM A36 structural steel product page",
        "id": "ASTM A36 (SSAB)",
        "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
        "year": 2026,
        "kind": "datasheet",
        "license": "SSAB website (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Minimum elongation in 8 in, mill plate (SSAB datasheet)",
      "value": 18,
      "bound": "lower",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "mill plate and temper-leveled plate (SSAB product table)",
        "thickness": "0.100 to 6.00 in (2.54 to 152 mm)",
        "gauge": "8 in",
        "basis": "SSAB footnote: for plates wider than 24 in the requirement is reduced by two percentage points"
      },
      "method": "Mechanical properties table, minimum as printed",
      "status": "ground",
      "source": "ssab-a36",
      "where": "Mechanical Properties table, Elongation in 8 in (min %) row",
      "source_detail": {
        "title": "SSAB: ASTM A36 structural steel product page",
        "id": "ASTM A36 (SSAB)",
        "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
        "year": 2026,
        "kind": "datasheet",
        "license": "SSAB website (cited, not reproduced)"
      }
    },
    {
      "benchmark": "density",
      "label": "Density of A36 (Wikipedia)",
      "value": 7.8,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "not stated (general A36)",
        "thickness": "not stated",
        "temperature": "not stated",
        "basis": "Wikipedia prints 0.28 lb/in3 (7.8 g/cm3)"
      },
      "method": "Properties section, value in g/cm3 as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, first paragraph (density)",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Young's modulus of A36 (Wikipedia)",
      "value": 200,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "not stated (general A36)",
        "thickness": "not stated",
        "temperature": "not stated",
        "basis": "Wikipedia prints 29,000 ksi (200 GPa)"
      },
      "method": "Properties section, value in GPa as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, Young's modulus sentence",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "shear_modulus",
      "label": "Shear modulus of A36 (Wikipedia)",
      "value": 79.3,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "not stated (general A36)",
        "thickness": "not stated",
        "temperature": "not stated",
        "basis": "Wikipedia prints 11,500 ksi (79.3 GPa)"
      },
      "method": "Properties section, value in GPa as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, Poisson's ratio and shear modulus sentence",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio of A36 (Wikipedia)",
      "value": 0.26,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "form": "not stated (general A36)",
        "thickness": "not stated",
        "temperature": "not stated",
        "basis": "Wikipedia prints 0.26 with no temperature or form"
      },
      "method": "Properties section, value as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, Poisson's ratio and shear modulus sentence",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity of A36 (Wikipedia)",
      "value": 0.142,
      "bound": "exact",
      "unit": "μΩ·m",
      "scope": "material",
      "conditions": {
        "form": "not stated (general A36)",
        "thickness": "not stated",
        "temperature": "68 °F (20 °C)",
        "basis": "Wikipedia calls it electrical resistance and prints 0.142 μΩm at 20 °C; the unit is a resistivity"
      },
      "method": "Properties section, value as printed",
      "status": "ground",
      "source": "wiki-a36",
      "where": "Properties section, electrical resistance sentence",
      "source_detail": {
        "title": "Wikipedia: A36 steel",
        "id": "A36 steel",
        "url": "https://en.wikipedia.org/wiki/A36_steel",
        "kind": "web",
        "license": "CC BY-SA 4.0 (cited, not reproduced)"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Outdoor air with moisture, unprotected steel",
      "headline": "Plain steel such as A36 rusts in ordinary outdoor air unless it is protected.",
      "effect": "Wikipedia states that structural steel cannot be exposed to the environment without suitable protection, because moisture or contact with water causes oxidation that compromises the structure.",
      "rating": "moderate",
      "conditions": {
        "exposure": "outdoor, moist air",
        "form": "structural steel (general)"
      },
      "source": "wiki-structural",
      "where": "Paragraph on exposure and protection (Structural steel)"
    },
    {
      "environment": "Uncoated or painted plain steel compared with weathering steel",
      "headline": "Weathering steel forms a stable rust layer that removes the need for paint, while painted weathering steel is no more corrosion-resistant than conventional steel.",
      "effect": "The protective patina needs the wetted surface to dry, and a small paint failure can start a localized attack (Wikipedia). A36 is conventional steel, not a weathering grade.",
      "rating": "moderate",
      "conditions": {
        "exposure": "outdoor",
        "comparison": "weathering steel versus conventional steel"
      },
      "source": "wiki-weathering",
      "where": "Properties section (patina) and the railcar history paragraph"
    },
    {
      "environment": "Steel coupled to copper or tin in a wet electrolyte",
      "headline": "Steel is the more reactive metal in these couples and corrodes faster where it touches the more noble metal.",
      "effect": "Galvanic corrosion needs an electrolyte and an electrical path. Wikipedia gives a marina example where a steel and copper couple acts as a battery of about 0.5 V, and says that when a tin coating on steel is broken the steel beneath is attacked at once.",
      "rating": "moderate",
      "conditions": {
        "electrolyte": "wet, salty or moist environment",
        "couple": "steel with copper or tin"
      },
      "source": "wiki-galvanic",
      "where": "Mechanism paragraph; tin can example; marina example"
    },
    {
      "environment": "Zinc-coated (galvanized) steel",
      "headline": "The zinc coating corrodes first and protects the steel until the zinc is used up.",
      "effect": "Wikipedia states that galvanizing protects the steel base metal by sacrificial anodic action, and that the underlying steel is not attacked even when the zinc coating is broken.",
      "rating": "low",
      "conditions": {
        "coating": "zinc"
      },
      "source": "wiki-galvanic",
      "where": "Galvanized iron example; mitigation paragraph on galvanizing"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem aggregated GHS for elemental manganese (Danger): H360 (may damage fertility or the unborn child), H370 (causes damage to organs), H372 (causes damage to organs through prolonged or repeated exposure) and H411 (toxic to aquatic life with long lasting effects). The record covers the element, not the solid A36 steel, which contains manganese up to 1.03 % (Wikipedia table).",
        "ghs": [
          "H360",
          "H370",
          "H372",
          "H411"
        ],
        "source": "pubchem-manganese",
        "where": "Safety and Hazards, GHS Classification"
      },
      {
        "text": "PubChem aggregated GHS for elemental iron: H319 (causes serious eye irritation) and H335 (may cause respiratory irritation), each in 100 % of reports. H228 and H251 also appear in some notifications. The record covers the element, not the solid A36 steel.",
        "ghs": [
          "H319",
          "H335",
          "H228",
          "H251"
        ],
        "source": "pubchem-iron",
        "where": "Safety and Hazards, GHS Classification"
      }
    ],
    "failure_risks": [
      {
        "mode": "Atmospheric rusting of unprotected steel",
        "trigger": "Moisture and oxygen at the surface, outdoors or in damp conditions, with no paint or galvanizing",
        "consequence": "Wikipedia says oxidation compromises the structural integrity of a building and endangers occupants and neighbors",
        "severity": "moderate",
        "source": "wiki-structural",
        "where": "Paragraph on exposure and protection"
      },
      {
        "mode": "Galvanic corrosion when coupled to a more noble metal",
        "trigger": "Electrical contact with copper or tin in a wet electrolyte",
        "consequence": "Steel becomes the anode and corrodes faster at the joint; a broken tin coating on steel is attacked at once",
        "severity": "moderate",
        "source": "wiki-galvanic",
        "where": "Mechanism paragraph; tin can example"
      },
      {
        "mode": "Strength loss above 650 °F (343 °C)",
        "trigger": "Sustained exposure above 650 °F (343 °C)",
        "consequence": "Minimum ultimate strength of bars and shapes falls to 54 ksi (370 MPa) at 700 °F (371 °C) and to 37 ksi (260 MPa) at 800 °F (427 °C)",
        "severity": "high",
        "source": "wiki-a36",
        "where": "Properties section, sentence on bars and shapes above 650 °F"
      },
      {
        "mode": "Loss of strength in fire",
        "trigger": "Fire exposure of unprotected steel",
        "consequence": "Wikipedia gives the critical temperature for steel members as about 530 to 810 °C in China, Europe and North America, set by the accepted fire-test standard",
        "severity": "high",
        "source": "wiki-structural",
        "where": "Fire resistance paragraph"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "A36 is readily welded by all welding processes, including shielded metal arc, gas metal arc and oxyacetylene welding (Wikipedia).",
        "source": "wiki-a36",
        "where": "Methods of joining"
      },
      {
        "text": "Protect the steel from moisture: paint or galvanize it before outdoor service, because uncoated steel in contact with water will oxidize (Wikipedia).",
        "source": "wiki-structural",
        "where": "Paragraph on exposure and protection"
      },
      {
        "text": "Keep copper and tin out of wet electrical contact with the steel, or stop the electrolyte path at the joint.",
        "source": "wiki-galvanic",
        "where": "Mitigation paragraph"
      },
      {
        "text": "The PubChem records cover elemental manganese and iron only. Check the supplier safety data sheet before cutting or welding; no A36 safety data sheet was fetched for this profile.",
        "source": "pubchem-iron",
        "where": "Safety and Hazards, GHS Classification (elemental records only)"
      }
    ],
    "mitigations": [
      {
        "text": "Galvanize the steel: zinc protects the steel base metal by sacrificial anodic action (Wikipedia).",
        "source": "wiki-galvanic",
        "where": "Mitigation paragraph"
      },
      {
        "text": "Paint or apply an impermeable coating to keep the electrolyte away; where only one metal can be coated, coat the more noble one (Wikipedia).",
        "source": "wiki-galvanic",
        "where": "Mitigation paragraph"
      },
      {
        "text": "Specify weathering steel for exposed work if a stable rust layer is wanted; it is a different grade from A36 (Wikipedia).",
        "source": "wiki-weathering",
        "where": "Lead paragraph"
      }
    ]
  },
  "uses": [
    {
      "application": "structures",
      "device": "General construction and structural framing",
      "example": "SSAB describes A36 as the steel for general construction and structural applications.",
      "source": "ssab-a36",
      "where": "General Product Description"
    },
    {
      "application": "structures",
      "device": "Girders, structural shapes and angle iron",
      "example": "A36 is produced as plates, structural shapes, bars, girders, angle iron and T iron.",
      "source": "wiki-a36",
      "where": "Fabricated forms"
    },
    {
      "application": "structures",
      "device": "Bolted and welded structural joints",
      "example": "A36 is readily welded by all welding processes and is also commonly bolted and riveted in structural applications.",
      "source": "wiki-a36",
      "where": "Methods of joining"
    }
  ],
  "supply": [
    {
      "subject": "Raw steel production by country (2025 estimate)",
      "abundance": "World raw steel 1,900 million t in 2025 (estimated, rounded); United States 82 million t in 2025 (estimated)",
      "producers": [
        {
          "country": "China",
          "share_percent": 51.6,
          "year": 2025
        },
        {
          "country": "India",
          "share_percent": 8.4,
          "year": 2025
        },
        {
          "country": "United States",
          "share_percent": 4.3,
          "year": 2025
        },
        {
          "country": "Japan",
          "share_percent": 4.3,
          "year": 2025
        },
        {
          "country": "Russia",
          "share_percent": 3.4,
          "year": 2025
        }
      ],
      "critical_lists": [],
      "recycling": "Not checked (USGS Iron and Steel Scrap chapter, not fetched)",
      "substitutes": [],
      "source": "usgs-iron-steel",
      "where": "World Production table, raw steel 2025e column"
    },
    {
      "subject": "US steel mill product imports and import reliance",
      "abundance": "US net import reliance 13 % of apparent consumption in 2025 (estimated); total steel mill product imports 24 million t in 2025 (estimated). Import sources 2021 to 2024: Canada 23 %, Mexico 15 %, Brazil 13 %, Republic of Korea 9 %, other 40 %.",
      "producers": [],
      "critical_lists": [],
      "recycling": "",
      "substitutes": [],
      "source": "usgs-iron-steel",
      "where": "Salient Statistics (net import reliance; imports total); Import Sources (2021 to 2024)"
    },
    {
      "subject": "US end uses, tariffs and substitutes",
      "abundance": "Construction took an estimated 31 % of 2025 net shipments, service centers and distributors 26 %, and automotive 15 %. Tariffs on steel imports rose to 50 % for all countries in June 2025. The normal trade relations duty is free for structural shapes (HTS 7216.00.0000) and hot-rolled bars and rods (7213.00.0000).",
      "producers": [],
      "critical_lists": [],
      "recycling": "",
      "substitutes": [
        "Iron and steel compete with aluminum and plastics in automotive, and with aluminum, concrete and wood in construction (USGS)"
      ],
      "source": "usgs-iron-steel",
      "where": "Domestic Production and Use; Events, Trends, and Issues; Tariff table; Substitutes"
    },
    {
      "subject": "Critical-mineral status",
      "abundance": "The USGS Iron and Steel chapter (2026) names no critical-minerals list. Iron ore and steel scrap are covered by other USGS chapters that were not fetched.",
      "producers": [],
      "critical_lists": [],
      "recycling": "",
      "substitutes": [],
      "source": "usgs-iron-steel",
      "where": "Whole chapter read; no critical-minerals list found"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "USGS Mineral Commodity Summaries 2026: Iron and Steel",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-steel.pdf",
      "year": 2026
    },
    {
      "title": "SSAB: ASTM A36 structural steel product page (mechanical properties)",
      "type": "datasheet",
      "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
      "year": 2026
    },
    {
      "title": "PubChem: Manganese (CID 23930), GHS classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON?heading=GHS+Classification",
      "year": 2026
    },
    {
      "title": "PubChem: Iron (CID 23925), GHS classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23925/JSON?heading=GHS+Classification",
      "year": 2026
    }
  ],
  "gaps": [
    "The ASTM A36/A36M standard text was not reached (astm.org blocked to the fetch). The minimum yield and tensile values come from the SSAB datasheet and from Wikipedia, which cites the Steel Construction Manual, not from the standard itself.",
    "Thermal conductivity for A36 was not found in a readable source. MakeItFrom returned a JavaScript cookie challenge and BeamDimensions a bot challenge in this run. The Engineering ToolBox thermal conductivity rows are for carbon steel at 0.5 %, 1 % and 1.5 % C (54, 43 and 36 W/m K at 20 °C), outside the A36 composition, so none is recorded.",
    "A36-specific specific heat, coefficient of thermal expansion and melting range were not found in a readable source. Generic carbon steel rows exist but are not recorded here because they are not A36 values.",
    "EN 10025 S235JR (1.0038), S275JR (1.0044), DIN St 37-2 and JIS SS 400 are not recorded as A36 designations. The Arvedi Group EN 10025-2 cross-reference table prints them for S235JR and S275JR only, and no readable source states that A36 is comparable to them. A worldwide equivalents guide found in search was not read.",
    "Hot rolling as the mill route is not confirmed in the fetched pages. SSAB lists mill plate and temper-leveled plate; Wikipedia lists plates, shapes, bars and girders.",
    "Atmospheric corrosion rate for A36 in micrometres per year was not reached. The ISO 9223 table at PMC returned a 403 block, and the MDPI 2024 atmospheric paper returned an HTML stub.",
    "No A36 safety data sheet was read. The hazard entries are PubChem records for elemental manganese and iron, not the solid alloy.",
    "Copper is listed as a maximum (0.20 %) in the Wikipedia table. The standard's copper requirement for copper-bearing grades was not read.",
    "Plate chemistry: the Wikipedia table is for shapes. The plate limits in ASTM A36 were not read from the standard.",
    "Critical-mineral lists: the USGS Iron and Steel chapter names none. The EU critical raw materials list was not read. Iron ore and steel scrap recycling are in other USGS chapters that were not read.",
    "Fatigue, hardness, Charpy toughness and low-temperature properties were not sourced.",
    "The 32 ksi (220 MPa) yield for plate over 8 in thick comes from Wikipedia only, not from SSAB, which lists thicknesses up to 6.00 in."
  ],
  "story": {
    "why": "A36 is the general-purpose structural carbon steel of the United States (Wikipedia, SSAB). It is readily welded by all processes and it keeps a 36 ksi minimum yield in plate under 8 in thick. Its weak point is that it is plain steel: it rusts outdoors and corrodes first when it touches copper or tin in a wet environment.",
    "uses": [
      {
        "where": "Building and general structural framing",
        "line": "SSAB describes A36 as the steel for general construction and structural applications. Structural steel is one of the most commonly used materials in commercial and industrial building construction (Wikipedia)."
      },
      {
        "where": "Girders and shapes",
        "line": "A36 is made as plates, structural shapes, bars, girders, angle iron and T iron (Wikipedia)."
      },
      {
        "where": "Welded and bolted joints",
        "line": "A36 is readily welded by all welding processes and is also commonly bolted and riveted in structural applications (Wikipedia)."
      }
    ],
    "can_do": [
      {
        "label": "Strength",
        "line": "Tensile strength runs from 58 to 80 ksi (400 to 550 MPa) for plate under 8 in thick (SSAB and Wikipedia).",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material"
      },
      {
        "label": "Yield",
        "line": "Minimum yield is 36 ksi (250 MPa) for plates, bars and shapes under 8 in, and 32 ksi (220 MPa) for plates over 8 in (Wikipedia).",
        "benchmark": "yield_strength",
        "scope": "material"
      },
      {
        "label": "Stiffness",
        "line": "Young's modulus is 200 GPa (29,000 ksi) and Poisson's ratio is 0.26 (Wikipedia).",
        "benchmark": "elastic_modulus",
        "scope": "material"
      },
      {
        "label": "Density",
        "line": "Density is 7.8 g/cm3, about 0.28 lb/in3 (Wikipedia).",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Ductility",
        "line": "Minimum elongation is 21 % in 2 in and 18 % in 8 in (SSAB).",
        "benchmark": "elongation",
        "scope": "material"
      },
      {
        "label": "Weldability",
        "line": "Readily welded by all welding processes, and bolted or riveted for structural joints (Wikipedia).",
        "scope": "material"
      }
    ],
    "compare": "A36 is a plain carbon structural steel and a common choice for structural framing in the United States. It is not a stainless grade, so it needs paint or galvanizing for outdoor life (Wikipedia). Its minimum yield of 36 ksi applies to plate under 8 in thick.",
    "compare_rows": [
      {
        "label": "Minimum yield strength",
        "benchmark": "yield_strength",
        "scope": "material"
      },
      {
        "label": "Tensile strength",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material"
      },
      {
        "label": "Stiffness",
        "benchmark": "elastic_modulus",
        "scope": "material"
      }
    ],
    "handling": [
      "Specify the thickness band with the strength. The 36 ksi yield applies to plate and shapes under 8 in thick, and 32 ksi applies above 8 in (Wikipedia).",
      "Protect the steel from moisture. Paint or galvanize it before outdoor service (Wikipedia).",
      "Check the supplier safety data sheet before cutting or welding. No A36 safety data sheet was read here."
    ],
    "good_for": [
      "Welded and bolted structural framing, girders and shapes in general construction (SSAB, Wikipedia).",
      "Parts that can be painted or galvanized and kept out of wet contact with copper or tin."
    ],
    "watch_out": [
      "Bare A36 rusts outdoors. The protective patina of weathering steel is a different grade, not A36 (Wikipedia).",
      "Galvanic corrosion: the steel corrodes first against copper or tin in a wet electrolyte (Wikipedia).",
      "Strength falls above 650 °F (343 °C), and fire reduces the minimum strength (Wikipedia)."
    ],
    "verdict": "A36 is the default plain structural carbon steel. It is easy to weld and bolt, and it has a 36 ksi minimum yield for thin plate and shapes. It is not corrosion resistant, so it must be painted or galvanized, and its minimum strength falls above 650 °F (343 °C). Thermal conductivity, specific heat, expansion and melting range for A36 itself are still open.",
    "recipe": {
      "line": "ASTM A36 (UNS K02600) is a low-carbon structural steel. Wikipedia gives its chemistry for shapes as 0.26 % carbon, 0.40 % silicon, 1.03 % manganese, 0.04 % phosphorus and 0.05 % sulfur maximum, with 0.20 % copper listed as a maximum and iron as the balance. Plate, bars, shapes and girders are made to this grade. The mill rolling route was not confirmed in the fetched pages.",
      "parts": [
        {
          "name": "Iron",
          "symbol": "Fe",
          "role": "The matrix of the steel, which makes up nearly all of it.",
          "share_note": "balance (the Wikipedia table lists 98.0 %)"
        },
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "Main strengthening element, held to a low maximum so the steel stays readily weldable.",
          "share_percent": 0,
          "share_high": 0.26
        },
        {
          "name": "Silicon",
          "symbol": "Si",
          "role": "Deoxidiser in the melt. Flanges over 3 in need a higher range (see identity).",
          "share_percent": 0,
          "share_high": 0.4
        },
        {
          "name": "Manganese",
          "symbol": "Mn",
          "role": "Adds strength. Flanges over 3 in need 0.85 to 1.35 % (see identity).",
          "share_percent": 0,
          "share_high": 1.03
        },
        {
          "name": "Phosphorus",
          "symbol": "P",
          "role": "Impurity held low.",
          "share_percent": 0,
          "share_high": 0.04
        },
        {
          "name": "Sulfur",
          "symbol": "S",
          "role": "Impurity held low.",
          "share_percent": 0,
          "share_high": 0.05
        },
        {
          "name": "Copper",
          "symbol": "Cu",
          "role": "Listed as a maximum in the Wikipedia table. The copper requirement for copper-bearing grades was not checked here.",
          "share_percent": 0,
          "share_high": 0.2
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The hazard records here are PubChem entries for elemental manganese and iron, not for the solid steel.",
        "points": [
          {
            "label": "Manganese",
            "line": "PubChem lists elemental manganese with H360 (may damage fertility or the unborn child), H370 and H372 (damage to organs, the second through repeated exposure), and H411 (toxic to aquatic life)."
          },
          {
            "label": "Iron",
            "line": "PubChem lists elemental iron with H319 and H335 (eye and respiratory irritation), each in 100 % of reports, and H228 and H251 in some notifications."
          },
          {
            "label": "Workshop",
            "line": "Check the supplier safety data sheet before cutting or welding. No A36 safety data sheet was fetched for this profile."
          }
        ],
        "level": 0,
        "verdict": "No A36 safety data sheet read"
      },
      {
        "title": "In the environment",
        "lead": "Plain carbon steel is not rust-resistant, so protection is the design choice.",
        "points": [
          {
            "label": "Rust",
            "line": "Structural steel cannot be left exposed without protection, because moisture or water causes oxidation (Wikipedia)."
          },
          {
            "label": "Galvanic",
            "line": "A steel and copper couple in a marina earth path acts as a battery of about 0.5 V (Wikipedia)."
          }
        ],
        "level": 1,
        "verdict": "Rust is the main outdoor risk"
      },
      {
        "title": "Heat and fire",
        "lead": "Bars and shapes keep their minimum strength up to 650 °F (343 °C), then lose it.",
        "points": [
          {
            "label": "Bars and shapes",
            "line": "The minimum ultimate strength falls from 58 ksi (400 MPa) to 54 ksi (370 MPa) at 700 °F and to 37 ksi (260 MPa) at 800 °F (Wikipedia)."
          },
          {
            "label": "Fire",
            "line": "Wikipedia gives about 530 to 810 °C as the critical temperature for steel members in China, Europe and North America, set by the accepted fire-test standard."
          }
        ],
        "level": 1,
        "verdict": "Strength falls above 650 °F (343 °C)"
      }
    ]
  },
  "updated": "2026-10-24",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 17,
    "unreachable": 4,
    "caveats": 7,
    "note": "Written by an AI assistant on 2026-10-24 from pages fetched in this run: SSAB ASTM A36 page, Wikipedia (A36 steel, Structural steel, Weathering steel, Galvanic corrosion), USGS MCS 2026 Iron and Steel, and PubChem GHS for manganese and iron. Not reached: ASTM A36 standard text, MakeItFrom, MatWeb, the PMC ISO 9223 table, and the MDPI 2024 paper. Second deepen pass, 2026-10-24: added the UNS K02600 (Wikipedia) and ASTM A36 (SSAB) designations; generic carbon steel rows for specific heat, expansion and melting range were found and left out because they are not A36 values. Not reached in this run: MakeItFrom and BeamDimensions (bot challenges), the MSU thesis (access denied)."
  },
  "sources": {
    "ssab-a36": {
      "title": "SSAB: ASTM A36 structural steel product page",
      "id": "ASTM A36 (SSAB)",
      "url": "https://www.ssab.com/en-us/brands-and-products/commercial-steel/structural-steel/astm-a36",
      "year": 2026,
      "kind": "datasheet",
      "license": "SSAB website (cited, not reproduced)"
    },
    "wiki-a36": {
      "title": "Wikipedia: A36 steel",
      "id": "A36 steel",
      "url": "https://en.wikipedia.org/wiki/A36_steel",
      "kind": "web",
      "license": "CC BY-SA 4.0 (cited, not reproduced)"
    },
    "wiki-structural": {
      "title": "Wikipedia: Structural steel",
      "id": "Structural steel",
      "url": "https://en.wikipedia.org/wiki/Structural_steel",
      "kind": "web",
      "license": "CC BY-SA 4.0 (cited, not reproduced)"
    },
    "wiki-weathering": {
      "title": "Wikipedia: Weathering steel",
      "id": "Weathering steel",
      "url": "https://en.wikipedia.org/wiki/Weathering_steel",
      "kind": "web",
      "license": "CC BY-SA 4.0 (cited, not reproduced)"
    },
    "wiki-galvanic": {
      "title": "Wikipedia: Galvanic corrosion",
      "id": "Galvanic corrosion",
      "url": "https://en.wikipedia.org/wiki/Galvanic_corrosion",
      "kind": "web",
      "license": "CC BY-SA 4.0 (cited, not reproduced)"
    },
    "usgs-iron-steel": {
      "title": "USGS Mineral Commodity Summaries 2026: Iron and Steel",
      "id": "mcs2026-iron-steel",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-steel.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain"
    },
    "pubchem-manganese": {
      "title": "PubChem: Manganese (CID 23930), GHS classification",
      "id": "CID 23930",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON?heading=GHS+Classification",
      "kind": "database",
      "license": "PubChem terms (public)"
    },
    "pubchem-iron": {
      "title": "PubChem: Iron (CID 23925), GHS classification",
      "id": "CID 23925",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23925/JSON?heading=GHS+Classification",
      "kind": "database",
      "license": "PubChem terms (public)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/steel-a36/"
}