{
  "spore": "profile",
  "id": "copper-c70250",
  "spore_version": "0.2",
  "family": "copper-alloys",
  "name": "Copper alloy C70250 (CuNi3SiMg)",
  "abbreviation": "CuNi3SiMg",
  "role": "precipitation-hardened spring and connector alloy",
  "category": "metals",
  "type": "copper-alloys",
  "summary": "Copper alloy C70250 (UNS C70250, CuNi3SiMg) is a precipitation-hardened copper alloy with 2.2 to 4.2 wt% nickel and 0.25 to 1.2 wt% silicon, per Aurubis. Aurubis gives a tensile strength of 655 to 830 MPa and a yield strength of 590 to 760 MPa in temper TM02, with an electrical conductivity of at least 23 MS/m (40 %IACS) in the soft condition.\n",
  "best_for": "Springs and connectors that need strength and electrical conduction together, without beryllium: 655 to 830 MPa tensile strength in temper TM02 and at least 40 %IACS in the soft condition",
  "weakest_at": "Electrical and thermal conduction, which is well below that of pure copper, and machining, which Fisk rates poor and Aurubis does not recommend",
  "identity": {
    "formula": "Copper alloy: Cu rest (Cu plus named elements 99.5 % minimum), Ni 2.2 to 4.2, Si 0.25 to 1.2, Mg 0.05 to 0.30, Zn up to 1.0, Pb up to 0.05, Fe up to 0.20, Mn up to 0.10 wt% (Aurubis US). Nominal Cu 96.3, Ni 3.0, Si 0.7 (Fisk). Nominal Ni 3, Si 0.65, Mg 0.15 (KME).",
    "designations": [
      {
        "system": "UNS",
        "code": "C70250",
        "source": "aurubis-us",
        "where": "Header, Comparable standards: UNS C70250"
      },
      {
        "system": "ASTM",
        "code": "B422",
        "source": "olin-c7025",
        "where": "Title block, ASTM B422 beside the alloy number"
      },
      {
        "system": "EN name",
        "code": "CuNi3Si",
        "note": "KME prints EN CuNi3Si; Kemper says EN not standardised",
        "source": "kme-cunisi",
        "where": "Alloy Designation table, EN row"
      },
      {
        "system": "Trade name",
        "code": "PNA 370",
        "note": "Aurubis designation",
        "source": "aurubis-pna370",
        "where": "Header, Aurubis designation"
      },
      {
        "system": "Trade name",
        "code": "C7025",
        "note": "Aurubis designation",
        "source": "aurubis-us",
        "where": "Header, Aurubis designations"
      }
    ],
    "source": "aurubis-us",
    "where": "Composition table of the Aurubis C70250 datasheet 18 08 US, and nominal composition of the Fisk Alloy page and the KME datasheet"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "electronics-and-chips",
      "mechanisms"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density, Aurubis PNA 370 datasheet",
      "value": 8.82,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "temper": "not stated",
        "unit_in_source": "g/cm³"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Physical properties table, Density column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, KME datasheet typical value",
      "value": 8.8,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "temper": "annealed (typical values, per KME)",
        "unit_in_source": "g/cm³"
      },
      "method": "Typical value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Physical Properties table, Density row",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, Fisk Alloy listing",
      "value": 8.94,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "temper": "not stated",
        "unit_in_source": "gm/cm³"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "note": "The Fisk value is higher than the Aurubis and KME values. The sources disagree and all three are recorded.",
      "source": "fisk-c70250",
      "where": "Physical properties, Metric units, Density",
      "source_detail": {
        "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
        "id": "ASTM B422; ASTM B888",
        "url": "https://fiskalloy.com/product/c70250/",
        "kind": "web"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, Aurubis PNA 370 datasheet",
      "value": 1095,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "pressure": "not stated"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "note": "Aurubis's two datasheets give different melting points, 1095 °C and 1062 °C. Both are recorded.",
      "source": "aurubis-pna370",
      "where": "Physical properties table, Melting point column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, Aurubis US datasheet",
      "value": 1062,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "unit_in_source": "1944 °F"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Physical properties table, metric row under the 1944 °F value, Melting point column",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, solidus (Fisk Alloy)",
      "value": 954,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "pressure": "not stated",
        "unit_in_source": "1,750 °F"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "fisk-c70250",
      "where": "Physical properties, Metric units, Melting Point (Solidus)",
      "source_detail": {
        "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
        "id": "ASTM B422; ASTM B888",
        "url": "https://fiskalloy.com/product/c70250/",
        "kind": "web"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, liquidus (Fisk Alloy)",
      "value": 1049,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "temperature": "not stated",
        "pressure": "not stated",
        "unit_in_source": "1,920 °F"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "fisk-c70250",
      "where": "Physical properties, Metric units, Melting Point (Liquidus)",
      "source_detail": {
        "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
        "id": "ASTM B422; ASTM B888",
        "url": "https://fiskalloy.com/product/c70250/",
        "kind": "web"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 20 °C, Aurubis US datasheet",
      "value": 169,
      "bound": "exact",
      "unit": "W/(m·K)",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "unit_in_source": "W/mK"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Physical properties table, Thermal cond. at 20 °C column, metric row",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 20 °C, Fisk Alloy listing",
      "value": 170,
      "bound": "exact",
      "unit": "W/(m·K)",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "unit_in_source": "W/m·K"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "fisk-c70250",
      "where": "Physical properties, Metric units, Thermal Conductivity",
      "source_detail": {
        "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
        "id": "ASTM B422; ASTM B888",
        "url": "https://fiskalloy.com/product/c70250/",
        "kind": "web"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, KME typical value",
      "value": 190,
      "bound": "exact",
      "unit": "W/(m·K)",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "temper": "annealed (typical values, per KME)"
      },
      "method": "Typical value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Physical Properties table, Thermal conductivity row",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "electrical_conductivity",
      "label": "Electrical conductivity, minimum, soft condition (Aurubis PNA 370)",
      "value": 23,
      "bound": "lower",
      "unit": "MS/m",
      "scope": "material",
      "conditions": {
        "temper": "soft condition only (the datasheet says the specified conductivity applies to the soft condition only)",
        "temperature": "not stated"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Physical properties table, Electrical cond. column (value 23 with a greater-than-or-equal sign)",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "electrical_conductivity",
      "label": "Electrical conductivity, minimum, soft condition (Aurubis PNA 370, %IACS)",
      "value": 40,
      "bound": "lower",
      "unit": "%IACS",
      "scope": "material",
      "conditions": {
        "temper": "soft condition only",
        "temperature": "not stated"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Description paragraph, 'min. 40% IACS'",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "electrical_conductivity",
      "label": "Electrical conductivity, Aurubis US datasheet",
      "value": 23.4,
      "bound": "exact",
      "unit": "MS/m",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "temper": "not stated",
        "note_in_source": "the same row gives 40 %IACS"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Physical properties table, Electrical cond. column, metric row",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity, annealed (Fisk Alloy)",
      "value": 4.31,
      "bound": "exact",
      "unit": "µΩ·cm",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "temper": "annealed",
        "unit_in_source": "µΩ·cm"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "fisk-c70250",
      "where": "Physical properties, Metric units, Electrical Resistivity (Annealed)",
      "source_detail": {
        "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
        "id": "ASTM B422; ASTM B888",
        "url": "https://fiskalloy.com/product/c70250/",
        "kind": "web"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity, Aurubis PNA 370 datasheet",
      "value": 130,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "not stated"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Physical properties table, Young's modulus column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity, Aurubis US datasheet",
      "value": 131,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "unit_in_source": "kN/mm2 and x1000 ksi (19)"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Physical properties table, Mod. of elasticity column, metric row",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, 20 to 300 °C, Aurubis PNA 370",
      "value": 17.6,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "temperature": "20 to 300 °C",
        "unit_in_source": "10-6/K"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Physical properties table, alpha at 20 to 300 °C column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, 20 to 300 °C, Olin Brass",
      "value": 17.6,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "temperature": "20 to 300 °C (68 to 572 °F)",
        "unit_in_source": "PPM/ºC"
      },
      "method": "Value printed in a manufacturer technical letter",
      "status": "ground",
      "source": "olin-c7025",
      "where": "Physical Properties table, Coeff. of Thermal Expansion, 68-572 ºF (20-300 ºC) row, metric column",
      "source_detail": {
        "title": "Olin Brass Alloy C7025 (C70250) technical data, ASTM B422",
        "id": "ASTM B422",
        "url": "https://www.wieland-rolledproductsna.com/wp-content/uploads/2018/08/Olin-Brass-Mill-Products-Technical-Letter-Alloy-C7025_0.pdf",
        "year": 2013,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat capacity at 20 °C, Aurubis PNA 370",
      "value": 0.399,
      "bound": "exact",
      "unit": "kJ/(kg·K)",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "unit_in_source": "kJ/kgK"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-pna370",
      "where": "Physical properties table, cp at 20 °C column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat capacity at 20 °C, Aurubis US",
      "value": 0.38,
      "bound": "exact",
      "unit": "kJ/(kg·K)",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "unit_in_source": "kJ/kgK"
      },
      "method": "Value printed in a manufacturer datasheet",
      "status": "ground",
      "note": "The Aurubis US sheet gives a lower value than the Aurubis PNA 370 sheet. Both are recorded.",
      "source": "aurubis-us",
      "where": "Physical properties table, Specific heat cap. at 20 °C column, metric row",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength, temper TM02 (Aurubis US)",
      "value": 655,
      "value_high": 830,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temper": "TM02",
        "product_form": "not stated",
        "unit_in_source": "95-120 ksi"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Mechanical properties table, Tempers TM02 row, Rm metric column",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength Rp0.2, temper TM02 (Aurubis US)",
      "value": 590,
      "value_high": 760,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temper": "TM02",
        "product_form": "not stated",
        "unit_in_source": "85-110 ksi"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Mechanical properties table, Tempers TM02 row, Rp0.2 metric column",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation, temper TM02 (Aurubis US), minimum",
      "value": 7,
      "bound": "lower",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "temper": "TM02",
        "gauge_length": "2 in. (column header Elongation 2)",
        "basis": "minimum"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Mechanical properties table, Tempers TM02 row, Elongation 2 column",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "vickers_hardness",
      "label": "Vickers hardness HV, temper TM02 (Aurubis US)",
      "value": 210,
      "value_high": 240,
      "bound": "range",
      "unit": "HV",
      "scope": "material",
      "conditions": {
        "temper": "TM02",
        "product_form": "not stated"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "aurubis-us",
      "where": "Mechanical properties table, Tempers TM02 row, Hardness HV column",
      "source_detail": {
        "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
        "id": "UNS C70250; Aurubis designations C7025 and PNA370",
        "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength, temper R690 (EN 1652, KME)",
      "value": 690,
      "value_high": 860,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temper": "R690 (EN 1652 temper)",
        "product_form": "strip",
        "thickness": "up to 0.5 mm for bending values only"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Mechanical Properties table (EN 1652), Tensile Strength Rm, row R690",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength Rp0.2, temper R690, minimum (KME)",
      "value": 655,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temper": "R690 (EN 1652 temper)",
        "product_form": "strip"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Mechanical Properties table (EN 1652), Yield Strength Rp0.2 minimum, row R690",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength Rp0.2, temper R690, minimum (Aurubis PNA 370)",
      "value": 650,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temper": "R690"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "note": "The Aurubis PNA 370 sheet gives 650 MPa as the minimum for R690, while KME gives 655 MPa. Both are recorded.",
      "source": "aurubis-pna370",
      "where": "Mechanical properties table, row R690, Yield strength column",
      "source_detail": {
        "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
        "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
        "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
        "year": 2026,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation A50, temper R690, minimum (KME)",
      "value": 5,
      "bound": "lower",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "temper": "R690",
        "gauge_length": "A50 mm"
      },
      "method": "Minimum value printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Mechanical Properties table, Elongation A50mm minimum, row R690",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "soft_annealing_temperature",
      "label": "Soft annealing temperature range (KME, not a canonical benchmark)",
      "value": 250,
      "value_high": 650,
      "bound": "range",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "time": "1 to 3 h",
        "purpose": "soft annealing (KME process data)"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Fabrication Properties table, row Soft Annealing",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    },
    {
      "benchmark": "stress_relief_temperature",
      "label": "Stress relieving annealing temperature range (KME, not a canonical benchmark)",
      "value": 150,
      "value_high": 200,
      "bound": "range",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "time": "1 to 3 h",
        "purpose": "stress relieving annealing (KME process data)"
      },
      "method": "Range printed in a manufacturer datasheet",
      "status": "ground",
      "source": "kme-cunisi",
      "where": "Fabrication Properties table, row Stress Relieving Annealing",
      "source_detail": {
        "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
        "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
        "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
        "year": 2019,
        "kind": "datasheet"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Natural and industrial atmospheres, maritime air, drinking and service water",
      "headline": "Good corrosion resistance in atmospheres (manufacturer statement, no rate printed).",
      "effect": "Aurubis PNA 370 lists resistance to natural and industrial atmospheres, maritime air, drinking and service water, non-oxidizing acids, alkaline solutions and neutral saline solutions. Aurubis US describes good corrosion resistance in industrial atmospheres. KME describes good corrosion resistance in natural atmosphere. No corrosion rate is printed in any of these sources.",
      "rating": "low",
      "conditions": {
        "basis": "manufacturer statements; no test conditions or corrosion rates given"
      },
      "source": "aurubis-pna370",
      "where": "Corrosion resistance section"
    },
    {
      "environment": "Stress corrosion cracking",
      "headline": "Not susceptible to stress corrosion cracking (Kemper and Aurubis US).",
      "effect": "Kemper's processing table lists stress crack corrosion as none. Aurubis US says the alloy is resistant against stress corrosion cracking. KME says it is insensitive to stress corrosion cracking.",
      "rating": "none",
      "conditions": {
        "basis": "manufacturer statements; no test data given"
      },
      "source": "kemper-khp7025",
      "where": "Processing information table, row Stress crack corrosion"
    },
    {
      "environment": "Ammonia, halide, cyanide and hydrogen sulphide solutions and atmospheres, oxidizing acids, sea water at high flow rates",
      "headline": "Not resistant to these environments (Aurubis PNA 370); no rate given.",
      "effect": "Aurubis PNA 370 lists these as environments in which the alloy is not resistant. The sheet gives no corrosion rate or test condition.",
      "rating": "unknown",
      "conditions": {
        "basis": "manufacturer statement; no rate or test condition printed"
      },
      "source": "aurubis-pna370",
      "where": "Corrosion resistance section, 'is not resistant to' sentence"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Wieland's copper alloy safety data sheet (SDS No. 00001.0001, revision 6/1/15) says the health hazards apply only in fume or dust form. Its OSHA classification lists skin irritation (H315) and respiratory irritation (H335) for fume or dust, and states that in solid form the material is not hazardous. The sheet covers UNS/CDA alloy numbers C10000 to C15599, which does not name C70250, so this is a related family sheet, not a sheet for this grade.",
        "ghs": [
          "H315",
          "H335"
        ],
        "source": "wieland-sds",
        "where": "Section 2, Hazard identification, and Section 3 regulatory status"
      },
      {
        "text": "The same sheet says that under 29 CFR 1910.1200 the product is considered hazardous, and lists dust or fume hazards as carcinogen, irritant, lung, blood, kidney, reproductive and developmental toxin, neurotoxin and sensitizer. The two statements apply to different forms (solid versus dust or fume).",
        "ghs": [],
        "source": "wieland-sds",
        "where": "Section 2, Other Hazards, and Section 3 OSHA regulatory status"
      }
    ],
    "failure_risks": [
      {
        "mode": "Loss of spring force in relaxation",
        "trigger": "Sustained stress at temperatures up to 150 °C",
        "consequence": "KME calls the relaxation properties excellent up to 150 °C because of NiSi precipitation. The Aurubis sheet plots residual stress against Larson-Miller parameter with no rate printed, so the loss of contact force cannot be quantified from these sources.",
        "severity": "moderate",
        "source": "kme-cunisi",
        "where": "Characteristics paragraph, and Relaxation Properties section"
      },
      {
        "mode": "Softening from overheating",
        "trigger": "Heating in the soft annealing range of 250 to 650 °C for 1 to 3 h",
        "consequence": "Soft annealing softens the material, so an unplanned excursion into this range lowers the strength of the spring temper. KME gives no strength figure after such heating.",
        "severity": "moderate",
        "source": "kme-cunisi",
        "where": "Fabrication Properties table, Soft Annealing row"
      },
      {
        "mode": "Attack in ammonia or sulphide environments",
        "trigger": "Exposure to ammonia, halide, cyanide or hydrogen sulphide solutions or atmospheres, oxidizing acids or sea water at high flow rates",
        "consequence": "Aurubis PNA 370 lists these as not resistant. No rate or time to failure is given.",
        "severity": "high",
        "source": "aurubis-pna370",
        "where": "Corrosion resistance section"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Use dust and fume controls when cutting, welding, melting or grinding the alloy. Avoid breathing dust or fumes (P261) and keep them off the skin and clothing (P262), per the Wieland sheet.",
        "source": "wieland-sds",
        "where": "Section 2, precautionary statements"
      },
      {
        "text": "After contact with dust or fumes, wash the skin with plenty of water and remove contaminated clothing before reuse, per the Wieland sheet's first aid section.",
        "source": "wieland-sds",
        "where": "Section 4, First aid measures"
      }
    ],
    "mitigations": []
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "Electronic connectors, contacts, lead frames and terminals",
      "example": "Aurubis lists contact springs, lead frames, electronic connectors and automotive electrical connectors as typical uses. Olin adds semiconductor leadframes and CPU sockets.",
      "source": "aurubis-us",
      "where": "Typical uses row; Olin introduction paragraph"
    },
    {
      "application": "mechanisms",
      "device": "Relay and contact springs",
      "example": "KME rates relay springs as a particularly well-suited application, and lists switches and relays among its main applications. Aurubis PNA 370 lists contact springs and relays among typical uses.",
      "source": "kme-cunisi",
      "where": "Preferred Applications table; Main Applications paragraph"
    },
    {
      "application": "electronics-and-chips",
      "device": "Beryllium-free replacement for some beryllium copper alloys",
      "example": "Olin says the alloy can often be substituted directly for some Be-Cu alloys. Fisk says it has the qualities of some beryllium coppers without containing any beryllium.",
      "source": "olin-c7025",
      "where": "Introduction paragraph; Fisk overview paragraph (fisk-c70250)"
    }
  ],
  "supply": [
    {
      "subject": "Copper (about 96 % of the alloy; Fisk prints Cu 96.3 nominal)",
      "abundance": "USGS mine production 2025e, copper content, thousand metric tons: Chile 5,300; Congo (Kinshasa) 3,200; Peru 2,700; China 1,800; Russia 1,300. World total 23,000. Reserves for the world total are 980,000 thousand t.",
      "producers": [
        {
          "country": "Chile",
          "year": 2025
        },
        {
          "country": "Congo (Kinshasa)",
          "year": 2025
        },
        {
          "country": "Peru",
          "year": 2025
        },
        {
          "country": "China",
          "year": 2025
        },
        {
          "country": "Russia",
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "U.S. Final 2025 List of Critical Minerals (copper added), per USGS Mineral Commodity Summaries 2026",
          "listed": true
        }
      ],
      "recycling": "USGS: old (post-consumer) scrap gave an estimated 160,000 tons of copper in 2025, and about 760,000 tons were recovered from new scrap. Scrap contributed about 30% of U.S. copper supply.",
      "substitutes": [
        "USGS: aluminum substitutes for copper in electrical equipment and power cable.",
        "Olin: the alloy can often be substituted directly for some Be-Cu alloys."
      ],
      "source": "usgs-mcs2026-copper",
      "where": "World Mine and Refinery Production and Reserves table; Recycling; Substitutes; Events, Trends, and Issues"
    },
    {
      "subject": "Silicon (alloying element, 0.25 to 1.2 wt%)",
      "abundance": "Silicon was added to the U.S. 2025 critical minerals list. Supply shares for silicon were not looked up in this run.",
      "producers": [],
      "critical_lists": [
        {
          "list": "U.S. Final 2025 List of Critical Minerals (silicon added), per USGS Mineral Commodity Summaries 2026",
          "listed": true
        }
      ],
      "substitutes": [],
      "source": "usgs-mcs2026-copper",
      "where": "Events, Trends, and Issues, second paragraph"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Aurubis technical datasheet C70250 (CuNi3SiMg), 18 08 US",
      "type": "datasheet",
      "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf"
    },
    {
      "title": "Aurubis material datasheet CuNi3SiMg, PNA 370, EN_2026_01",
      "type": "datasheet",
      "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
      "year": 2026
    },
    {
      "title": "Olin Brass Alloy C7025 technical data, ASTM B422",
      "type": "datasheet",
      "url": "https://www.wieland-rolledproductsna.com/wp-content/uploads/2018/08/Olin-Brass-Mill-Products-Technical-Letter-Alloy-C7025_0.pdf",
      "year": 2013
    },
    {
      "title": "KME CuNi3Si1Mg (C70250) industrial rolled datasheet",
      "type": "datasheet",
      "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
      "year": 2019
    },
    {
      "title": "Fisk Alloy C70250 product page",
      "type": "datasheet",
      "url": "https://fiskalloy.com/product/c70250/"
    },
    {
      "title": "Kemper KHP 7025 (CuNi3SiMg) alloy page",
      "type": "datasheet",
      "url": "https://www.kemper-group.com/en-en/rolled-products/alloys/khp7025-(cuni3simg)/"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: copper",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf",
      "year": 2026
    },
    {
      "title": "Wieland copper alloy safety data sheet, SDS No. 00001.0001",
      "type": "sds",
      "url": "https://www.wieland.com/fr/content/download/12648/file/Safety-Data-Sheet_Copper-alloy.pdf",
      "year": 2015
    }
  ],
  "gaps": [
    "No safety data sheet for C70250 itself was found. The hazard entries use Wieland's copper alloy sheet, whose synonym line covers a range of copper alloy UNS/CDA numbers that does not name C70250. The three Fisk Alloy safety sheets checked cover other alloys.",
    "PubChem could not be read in this run (the page returned a browser check), so no ECHA or GHS classification record was added for this alloy or for copper.",
    "Only the tempers TM00, TM02, TM03 (Aurubis US, Olin) and R620, R650, R690 (Aurubis PNA 370, KME) were read in full. The highest EN 1652 temper shown by Kemper was not recorded.",
    "Kemper's datasheet gives strength ranges for the same EN 1652 temper designations that differ from KME's ranges. Kemper strength values were not recorded; the KME values were kept.",
    "Stress relaxation rates were not recorded. KME and Aurubis publish relaxation data as plots only. Sundwiger and Wieland datasheets found in search were not readable.",
    "Fisk's modulus of elasticity entry is in a unit that does not match the other sources and was not recorded. Fisk's conductivity entries are in units that were not converted, so they were not recorded.",
    "Vickers hardness (HV) and soft annealing and stress relief temperatures are recorded under benchmark names that are not in the canonical list (vickers_hardness, soft_annealing_temperature, stress_relief_temperature).",
    "Electrical resistivity and conductivity of the spring tempers were not found as numbers. KME says cold deformation lowers conductivity without giving a value.",
    "Corrosion rates in micrometres per year, and salt spray or atmospheric exposure results, were not found in any source read.",
    "The EN number (1.xxxx) and the CW112C designation were not printed in any source read. KME prints 'EN CuNi3Si' while Kemper states 'EN not standardised'; the KME name is recorded with that conflict noted.",
    "Nickel and magnesium supply (producers, shares and critical lists) were not looked up. Only copper and silicon are covered in the supply section.",
    "Radiation tolerance, outgassing and flight heritage were not looked up. No space application or flight record was found in the sources read.",
    "The Aurubis sheets give specific heat as 0.399 and 0.38 kJ/kgK, and melting point as 1095 and 1062 °C; both are recorded as printed, and the disagreement is noted on each row."
  ],
  "story": {
    "why": "Copper alloy C70250 (UNS C70250, CuNi3SiMg) is a precipitation-hardened copper alloy for springs, connectors and lead frames. Aurubis gives a tensile strength of 655 to 830 MPa and a yield strength of 590 to 760 MPa in temper TM02, with an electrical conductivity of at least 23 MS/m (40 %IACS) in the soft condition. Pure copper conducts better; this alloy trades some conduction for strength and spring behaviour. Olin says it can often replace some beryllium copper alloys.",
    "uses": [
      {
        "where": "Connectors and contacts",
        "line": "Aurubis lists contact springs, lead frames, electronic connectors and automotive electrical connectors as typical uses. Olin adds semiconductor leadframes and CPU sockets."
      },
      {
        "where": "Relay and switch springs",
        "line": "KME rates relay springs as particularly well-suited applications, and lists switches and relays among its main applications."
      },
      {
        "where": "Replacement for beryllium copper",
        "line": "Olin says the alloy can often be substituted directly for some Be-Cu alloys. Fisk says it has some of the qualities of beryllium coppers without containing any beryllium."
      }
    ],
    "can_do": [
      {
        "label": "Strength",
        "line": "In temper TM02 the tensile strength is 655 to 830 MPa, and the yield strength is 590 to 760 MPa (Aurubis US datasheet).",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material",
        "value": "655 to 830 MPa"
      },
      {
        "label": "Conductivity",
        "line": "In the soft condition the minimum electrical conductivity is 23 MS/m, or 40 %IACS (Aurubis PNA 370 datasheet). Aurubis says this applies to the soft condition only.",
        "benchmark": "electrical_conductivity",
        "scope": "material",
        "value": "23 MS/m minimum"
      },
      {
        "label": "Heat conduction",
        "line": "Thermal conductivity is 169 W/(m·K) at 20 °C in the Aurubis US datasheet, 170 W/(m·K) in the Fisk listing and 190 W/(m·K) as a typical value in the KME datasheet.",
        "benchmark": "thermal_conductivity",
        "scope": "material",
        "value": "169 W/(m·K) at 20 °C"
      },
      {
        "label": "Spring relaxation",
        "line": "KME says the relaxation properties are excellent even at temperatures up to 150 °C. Aurubis gives relaxation only as a plot, so no relaxation rate is recorded here.",
        "scope": "material"
      },
      {
        "label": "Stress corrosion",
        "line": "Kemper lists stress crack corrosion as none, and Aurubis US says the alloy is resistant against stress corrosion cracking.",
        "scope": "material"
      }
    ],
    "compare": "C70250 is a precipitation-hardened copper alloy. It gives up some of the conduction of pure copper in exchange for much higher strength and good stress relaxation resistance, and it keeps the spring behaviour that copper alone lacks. Olin and Fisk both present it as a beryllium-free substitute for some beryllium copper alloys, and the beryllium copper profile in this collection can be read against these claims. The table compares it on the three benchmarks the collection uses.",
    "compare_rows": [
      {
        "label": "Electrical conductivity",
        "benchmark": "electrical_conductivity",
        "scope": "material"
      },
      {
        "label": "Tensile strength",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material"
      },
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      }
    ],
    "handling": [
      "The solid alloy is not hazardous in solid form under the Wieland copper alloy safety data sheet. Dust and fume from cutting, welding, melting and grinding are the hazard.",
      "Avoid breathing dust or fumes (P261) and keep them off skin and clothing (P262).",
      "Keep the alloy away from ammonia, halide, cyanide and hydrogen sulphide solutions, oxidizing acids and sea water at high flow rates (Aurubis PNA 370).",
      "Soft annealing is 250 to 650 °C for 1 to 3 h and stress relief is 150 to 200 °C for 1 to 3 h (KME). Heating in these ranges changes the temper."
    ],
    "good_for": [
      "Spring contacts and connectors that need strength and conduction together: 655 to 830 MPa tensile strength in TM02 and at least 40 %IACS in the soft condition.",
      "A beryllium-free alternative for some beryllium copper connectors, as Olin and Fisk describe it."
    ],
    "watch_out": [
      "Conductivity is lower in cold-worked and hard tempers. Aurubis says the specified conductivity applies to the soft condition only.",
      "Not resistant to ammonia, halide, cyanide or hydrogen sulphide solutions and atmospheres, oxidizing acids or sea water at high flow rates (Aurubis PNA 370).",
      "Machinability is rated poor by Fisk and not recommended by Aurubis US."
    ],
    "verdict": "C70250 is the choice for springs and connectors that need strength and conduction without beryllium, as long as the part avoids ammonia and sulphide environments.",
    "recipe": {
      "line": "Copper alloy C70250 is copper with nickel and silicon, plus small additions of magnesium, made to temper by cold working and heat treatment at the mill (Fisk). In heat treatment the nickel and silicon form NiSi precipitates (KME), which give the strength and the stress relaxation resistance.",
      "parts": [
        {
          "name": "Copper",
          "symbol": "Cu",
          "role": "The matrix. Copper carries the electrical and thermal conduction, and the alloy keeps its conductivity at 40 %IACS minimum in the soft condition.",
          "share_note": "balance (rest)",
          "source": "aurubis-us",
          "where": "Composition table, Cu row: rem, with Cu plus named elements 99.5 % minimum"
        },
        {
          "name": "Nickel",
          "symbol": "Ni",
          "role": "Forms NiSi precipitates with silicon during heat treatment, which hardens the alloy.",
          "share_percent": 2.2,
          "share_high": 4.2,
          "source": "aurubis-us",
          "where": "Composition table, Ni column"
        },
        {
          "name": "Silicon",
          "symbol": "Si",
          "role": "Combines with nickel to form the NiSi precipitates.",
          "share_percent": 0.25,
          "share_high": 1.2,
          "source": "aurubis-us",
          "where": "Composition table, Si column"
        },
        {
          "name": "Magnesium",
          "symbol": "Mg",
          "role": "A minor addition. KME gives 0.15 wt% as the nominal magnesium content.",
          "share_percent": 0.05,
          "share_high": 0.3,
          "source": "aurubis-us",
          "where": "Composition table, Mg column"
        }
      ]
    },
    "risk_groups": [
      {
        "title": "Solid alloy",
        "lead": "The Wieland copper alloy safety data sheet says the solid metal is not hazardous. No sheet for C70250 itself was found.",
        "points": [
          {
            "label": "Solid form",
            "line": "The Wieland sheet's OSHA statement says that in solid form the material is not hazardous. Its family sheet covers C10000 to C15599, which does not name C70250."
          },
          {
            "label": "Processing",
            "line": "Cutting, welding, melting and grinding produce dust and fume that carry the alloy's component elements into the air."
          }
        ],
        "level": 0,
        "verdict": "Not hazardous in solid form"
      },
      {
        "title": "Dust and fume",
        "lead": "The health hazards apply to dust or fume, not to the solid metal, according to the Wieland sheet.",
        "points": [
          {
            "label": "Hazard statements",
            "line": "H315 causes skin irritation and H335 may cause respiratory irritation, for dust or fume (Wieland sheet)."
          },
          {
            "label": "Precautions",
            "line": "Avoid breathing dust or fumes (P261). Do not get them in the eyes, on the skin or on clothing (P262)."
          }
        ],
        "level": 2,
        "verdict": "Irritant dust and fume while processing"
      }
    ]
  },
  "updated": "2026-10-16",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 30,
    "unreachable": 0,
    "caveats": 0,
    "note": "Values read in this run from the Aurubis, Olin, KME, Fisk and Kemper pages and the USGS summary. Sundwiger and Wieland datasheets for other copper alloys were not readable."
  },
  "sources": {
    "aurubis-us": {
      "title": "Technical Datasheet C70250 (CuNi3SiMg), Aurubis, 18 08 US",
      "id": "UNS C70250; Aurubis designations C7025 and PNA370",
      "url": "https://www.aurubis.be/en/dam/jcr:168e88f6-00e4-41a8-9f07-246f75e99273/c70250-cuni3simg-us.pdf",
      "kind": "datasheet"
    },
    "aurubis-pna370": {
      "title": "Material Datasheet CuNi3SiMg, Aurubis PNA 370, EN_2026_01",
      "id": "Comparable standards UNS C70250; Aurubis designation PNA 370",
      "url": "https://www.aurubis.com/en/dam/jcr:ecd0d61d-f7f8-4a87-9fe6-c08c681323a1/PNA%20370_CuNi3SiMg_C70250-En.pdf",
      "year": 2026,
      "kind": "datasheet"
    },
    "olin-c7025": {
      "title": "Olin Brass Alloy C7025 (C70250) technical data, ASTM B422",
      "id": "ASTM B422",
      "url": "https://www.wieland-rolledproductsna.com/wp-content/uploads/2018/08/Olin-Brass-Mill-Products-Technical-Letter-Alloy-C7025_0.pdf",
      "year": 2013,
      "kind": "datasheet"
    },
    "kme-cunisi": {
      "title": "KME CuNi3Si1Mg (C70250), Industrial Rolled, High Performance Alloys datasheet",
      "id": "EN CuNi3Si; UNS C70250; DIN CEN/TS 13388",
      "url": "https://www.kme-archiv.com/fileadmin/DOWNLOADCENTER/COPPER%20DIVISON/4%20Industrial%20Rolled/3_Datasheets/3_Datasheets_new_2019/CuNi3Si_04_2019.pdf",
      "year": 2019,
      "kind": "datasheet"
    },
    "fisk-c70250": {
      "title": "C70250 High Performance Alloy (CuNi3Si1), Fisk Alloy product page",
      "id": "ASTM B422; ASTM B888",
      "url": "https://fiskalloy.com/product/c70250/",
      "kind": "web"
    },
    "kemper-khp7025": {
      "title": "KHP 7025 (CuNi3SiMg), Gebr. Kemper rolled products alloy page",
      "id": "Standard designation: EN not standardised / UNS C70250",
      "url": "https://www.kemper-group.com/en-en/rolled-products/alloys/khp7025-(cuni3simg)/",
      "kind": "datasheet"
    },
    "usgs-mcs2026-copper": {
      "title": "USGS Mineral Commodity Summaries 2026: Copper",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf",
      "year": 2026,
      "kind": "report"
    },
    "wieland-sds": {
      "title": "Wieland copper alloy safety data sheet, SDS No. 00001.0001 (revision 6/1/15)",
      "id": "UNS/CDA Alloy Nos. c10000 to c15599 (except 15815)",
      "url": "https://www.wieland.com/fr/content/download/12648/file/Safety-Data-Sheet_Copper-alloy.pdf",
      "year": 2015,
      "kind": "datasheet"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/copper-c70250/"
}