spore: profile id: tin-bronze-c90500 spore_version: 0.2 family: copper-alloys name: Tin bronze C90500 (SAE 62 gunmetal) abbreviation: C90500 role: bearing and gear casting alloy category: metals type: copper-alloys summary: | Tin bronze C90500 (SAE 62 gunmetal, also printed as gun metal) is a copper-tin-zinc casting alloy designated UNS C90500. Its continuous-cast form has a density of 8.72 g/cm3 at 20 °C, a minimum tensile strength of 303 MPa and a minimum yield strength of 172 MPa at 0.5 % extension under load. Its electrical conductivity is 11 %IACS, far below that of pure copper. Concast and National Bronze name it for gears, bushings and bearings that carry heavy loads at low speed. No space flight or outgassing data for this alloy were found in the sources used. best_for: Heavy-load, low-speed bushings, bearings and gears in a copper-tin casting alloy (UNS C90500) weakest_at: Electrical conduction at 11 %IACS, and no space flight or outgassing data were found for this grade identity: formula: 'Cu-Sn-Zn casting bronze: copper 86.0 to 89.0 %, tin 9.0 to 11.0 %, zinc 1.0 to 3.0 %, lead 0.30 % maximum (minimum and maximum composition per ASTM B505 in the Concast datasheet); nominal copper 87.5 %, tin 10.0 %, zinc 2.0 % (National Bronze)' source: concast-c90500 where: Chemical composition table of the Concast C90500 datasheet; nominal values from the Specifications table of the National Bronze C90500 page designations: - system: UNS code: C90500 source: concast-c90500 where: Machinability table, row Copper alloy UNS no. C90500 - system: ASTM code: B505 note: continuous castings; composition and mechanical properties per ASTM B505/B505M-23 source: concast-c90500 where: Chemical composition and Mechanical properties headings - system: ASTM code: B22 note: listed as a similar or equivalent specification source: concast-c90500 where: Similar or equivalent specification table, ASTM column - system: SAE code: '62' note: SAE 62 gear bronze source: nationalbronze-c90500 where: Page heading C90500 (SAE62) Bronze tags: environments: [] stresses: [] applications: - mechanisms - structures - electronics-and-chips properties: - benchmark: density label: Density, tin bronze C90500 (continuous cast) value: 8.72 unit: g/cm3 scope: material conditions: grade: C90500 temperature: 20 °C unit_in_source: 8.72 gm/cm3 at 20˚C (0.315 lb/in3 at 68 °F) method: Value printed in a manufacturer datasheet, physical properties table (CDA data) status: ground source: concast-c90500 where: Physical properties table, row Density, metric column - benchmark: melting_point label: Liquidus temperature, tin bronze C90500 value: 999 unit: °C scope: material conditions: grade: C90500 point: liquidus unit_in_source: 1830 °F method: Value printed in a manufacturer datasheet, physical properties table (CDA data) status: ground source: concast-c90500 where: Physical properties table, row Melting point liquidus, metric column - benchmark: melting_point label: Solidus temperature, tin bronze C90500 value: 854 unit: °C scope: material conditions: grade: C90500 point: solidus unit_in_source: 1570 °F method: Value printed in a manufacturer datasheet, physical properties table (CDA data) status: ground source: concast-c90500 where: Physical properties table, row Melting point solidus, metric column - benchmark: thermal_conductivity label: Thermal conductivity, tin bronze C90500 value: 74.8 unit: W/(m·K) scope: material conditions: grade: C90500 temperature: 20 °C unit_in_source: 74.8 W/m at 20°C (the datasheet prints W/m with no kelvin term) method: Value printed in a manufacturer datasheet; the source prints the unit as W/m, read here as W/(m·K), the unit a thermal conductivity requires status: ground source: concast-c90500 where: Physical properties table, row Thermal conductivity, metric column - benchmark: electrical_conductivity label: Electrical conductivity, tin bronze C90500 value: 11 unit: '%IACS' scope: material conditions: grade: C90500 temperature: 68 °F (20 °C) unit_in_source: 11% IACS at 68˚F method: Value printed in a manufacturer datasheet, physical properties table (CDA data) status: ground source: concast-c90500 where: Physical properties table, row Electrical conductivity, US customary column - benchmark: elastic_modulus label: Modulus of elasticity in tension, tin bronze C90500 value: 103400 unit: MPa scope: material conditions: grade: C90500 loading: tension temperature: not printed unit_in_source: 15000 ksi method: Value printed in a manufacturer datasheet, physical properties table (CDA data); the row is labelled modulus of elasticity in tension status: ground source: concast-c90500 where: Physical properties table, row Modulas of elasticity in tension (source spelling), metric column - benchmark: specific_heat label: Specific heat capacity, tin bronze C90500 value: 377.1 unit: J/kg scope: material conditions: grade: C90500 temperature: 20 °C unit_in_source: 377.1 J/kg at 20˚C (0.09 Btu/lb/°F at 68 °F) unit_note: the source prints J/kg with no kelvin term method: Value printed in a manufacturer datasheet, physical properties table (CDA data) status: ground source: concast-c90500 where: Physical properties table, row Specific heat capacity, metric column - benchmark: yield_strength label: Yield strength at 0.5 % extension under load, continuous cast minimum value: 172 bound: lower unit: MPa scope: material conditions: grade: C90500 form: continuous cast (ASTM B505 minimum) measure: 0.5 % extension under load temperature: 68 °F (20 °C) unit_in_source: 25 ksi method: Minimum mechanical property printed in a manufacturer datasheet under ASTM B505/B505M-23 status: ground source: concast-c90500 where: Mechanical properties table, min columns, yield strength at 0.5 % extension under load - benchmark: ultimate_tensile_strength label: Tensile strength, continuous cast minimum value: 303 bound: lower unit: MPa scope: material conditions: grade: C90500 form: continuous cast (ASTM B505 minimum) temperature: 68 °F (20 °C) unit_in_source: 44 ksi method: Minimum mechanical property printed in a manufacturer datasheet under ASTM B505/B505M-23 status: ground source: concast-c90500 where: Mechanical properties table, min columns, tensile strength - benchmark: elongation label: Elongation, continuous cast minimum value: 10 bound: lower unit: '%' scope: material conditions: grade: C90500 form: continuous cast (ASTM B505 minimum) gauge_length: 2 in. or 50 mm method: Minimum mechanical property printed in a manufacturer datasheet under ASTM B505/B505M-23 status: ground source: concast-c90500 where: Mechanical properties table, min columns, elongation - benchmark: hardness_brinell label: Brinell hardness, typical, continuous cast value: 75 unit: BHN scope: material conditions: grade: C90500 form: continuous cast load: 500 kg typ_min: typical method: Typical value printed in a manufacturer datasheet (Brinell hardness at 500 kg load) status: ground source: concast-c90500 where: Mechanical properties table, Brinell hardness (500 kg load), typical BHN - benchmark: ultimate_tensile_strength label: Tensile strength, sand cast typical (temper M01) value: 310 unit: MPa scope: material conditions: grade: C90500 form: sand cast, temper M01 typ_min: typical (TYP) temperature: 68 °F (20 °C) unit_in_source: 45 ksi method: Typical value printed in a supplier datasheet table; a different product form from the continuous-cast values above status: ground source: nationalbronze-c90500 where: Mechanical properties table, row As Sand Cast M01 TYP, tensile strength - benchmark: yield_strength label: Yield strength at 0.5 % extension under load, sand cast typical (temper M01) value: 152 unit: MPa scope: material conditions: grade: C90500 form: sand cast, temper M01 typ_min: typical (TYP) measure: 0.5 % extension under load temperature: 68 °F (20 °C) unit_in_source: 22 ksi method: Typical value printed in a supplier datasheet table; a different product form from the continuous-cast values above status: ground source: nationalbronze-c90500 where: Mechanical properties table, row As Sand Cast M01 TYP, yield strength column - benchmark: elongation label: Elongation, sand cast typical (temper M01) value: 25 unit: '%' scope: material conditions: grade: C90500 form: sand cast, temper M01 typ_min: typical (TYP) gauge_length: not printed method: Typical value printed in a supplier datasheet table; a different product form from the continuous-cast values above status: ground source: nationalbronze-c90500 where: Mechanical properties table, row As Sand Cast M01 TYP, elongation column - benchmark: ultimate_tensile_strength label: Tensile strength, centrifugal cast minimum as-cast (ASTM B271) value: 276 bound: lower unit: MPa scope: material conditions: grade: C90500 form: centrifugal casting, as-cast (ASTM B271 minimum) unit_in_source: 276 min. (Mpa) method: Minimum mechanical property printed in a supplier datasheet under ASTM B271, as-cast heat treatment; a different product form from the continuous-cast values above status: ground source: icast-c90500 where: Mechanical Properties table, row Tensile Strength in Mpa, 276 min. - benchmark: yield_strength label: Yield strength, centrifugal cast minimum as-cast (ASTM B271) value: 124 bound: lower unit: MPa scope: material conditions: grade: C90500 form: centrifugal casting, as-cast (ASTM B271 minimum) measure: not printed unit_in_source: 124 min. (Mpa) method: Minimum mechanical property printed in a supplier datasheet under ASTM B271, as-cast heat treatment; a different product form from the continuous-cast values above status: ground source: icast-c90500 where: Mechanical Properties table, row Yield Strength in Mpa, 124 min. corrosion: - environment: Steam and salt water headline: General gunmetal, the family that includes C90500, is described as resistant to corrosion from steam and salt water. effect: Wikipedia says gunmetal casts and machines well and is resistant to corrosion from steam and salt water. The article gives no corrosion rate and no test data for C90500 specifically. rating: low conditions: basis: general gunmetal description, not a C90500 test exposure: steam and salt water, no duration stated source: wikipedia-gunmetal where: Gunmetal article, corrosion sentence risks: hazards: - text: The copper in the alloy carries the PubChem copper classification. ECHA aggregated hazard codes for copper are H302 at 21.7 %, H400 at 43.1 %, H410 at 18.8 % and H411 at 22.5 % of the company reports that gave codes (1645 of 3463 reports). The remaining 1818 reports, which is 52.5 %, state that copper does not meet GHS criteria. ghs: - H302 - H400 - H410 - H411 source: pubchem-cu where: GHS Classification section, ECHA C&L Notifications Summary, copper CID 23978 - text: Lead is present in C90500 at a 0.30 % maximum in the Concast composition table. No lead hazard statement or safety data sheet for this alloy was read. ghs: [] source: concast-c90500 where: Chemical composition table, column Pb failure_risks: - mode: Permanent deformation under heavy load trigger: Stress above the 172 MPa minimum yield strength (0.5 % extension under load) of the continuous-cast form consequence: Permanent set in a bushing or bearing. No service or wear data for C90500 were read. severity: moderate source: concast-c90500 where: Mechanical properties table; uses described on the Concast product page side_effects: [] handling: - text: Brazing is done within the hot-short range, so strain must be avoided during brazing and cooling. source: concast-c90500 where: Fabrication properties note under the table - text: The solidus is 854 °C and the liquidus is 999 °C. The CDA casting table rates shrinkage in solidification as medium and drossing as low, so the foundry must plan feeding for a casting with that freezing range. source: concast-c90500 where: Physical properties table (melting points); Casting characteristics table (shrinkage in solidification, drossing) mitigations: [] uses: - application: mechanisms device: Gears, bushings and bearings example: Concast describes gear and high-strength bushing and bearing applications where high strength, low speeds and heavy loads are present. source: concast-c90500-page where: Uses and applications section - application: structures device: Movable bridge components and bridge turntables example: Concast lists movable bridge components, turntables for bridges, and other structures for fixed and expansion bearings. source: concast-c90500-page where: Uses and applications section - application: electronics-and-chips device: Electrical connectors example: The Concast typical-uses column lists electrical connectors, plumbing steam fittings and water conditioners, and pump impellers and valve bodies among the uses. source: concast-c90500 where: Typical uses column supply: - subject: Tin (9.0 to 11.0 % of the alloy) producers: - country: China share_percent: 24.5 year: 2025 - country: Indonesia share_percent: 21 year: 2025 - country: Peru share_percent: 11.4 year: 2025 - country: Brazil share_percent: 9.7 year: 2025 critical_lists: [] recycling: 'USGS: about 17,000 tons of tin from old and new scrap was estimated to be recycled in 2025, accounting for 22% of apparent consumption.' substitutes: - 'USGS: aluminum, glass, paper, plastic or tin-free steel substitute for tin in cans and containers; aluminum alloys, alternative copper-base alloys and plastics substitute for tin in bronze.' source: usgs-tin-2026 where: World Mine Production table, 2025e column (world total 290,000 t; China 71,000 t, Indonesia 61,000 t, Peru 33,000 t, Brazil 28,000 t). Shares calculated by Space Mushroom from those tonnes. Recycling and Substitutes paragraphs. - subject: Copper (86.0 to 89.0 % of the alloy) producers: - country: Chile share_percent: 23 year: 2025 - country: Congo (Kinshasa) share_percent: 13.9 year: 2025 - country: Peru share_percent: 11.7 year: 2025 - country: China share_percent: 7.8 year: 2025 critical_lists: - list: U.S. Final 2025 List of Critical Minerals (copper added) listed: true recycling: 'USGS: old scrap provided 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; plastics substitute for copper in drain pipe and plumbing fixtures.' source: usgs-copper-2026 where: World Mine and Refinery Production table, mine production 2025e column (world total 23,000 thousand t of copper content; Chile 5,300, Congo (Kinshasa) 3,200, Peru 2,700, China 1,800). Shares calculated by Space Mushroom from those values. Recycling, Critical Minerals and Substitutes paragraphs. documents: - title: Wieland Concast datasheet, C90500 tin bronze (continuous cast) type: datasheet url: https://www.concast.com/files/C90500.pdf - title: National Bronze and Metals, C90500 (SAE62) Bronze type: datasheet url: https://nationalbronze.com/C90500_Gear_Bronze.php - title: USGS Mineral Commodity Summaries 2026, Tin type: report url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tin.pdf year: 2026 - title: USGS Mineral Commodity Summaries 2026, Copper type: report url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf year: 2026 - title: PubChem compound record for copper, CID 23978 type: database url: https://pubchem.ncbi.nlm.nih.gov/compound/Copper - title: ICAST Alloys, ASTM B271 Tin Bronze UNS C90500 datasheet type: datasheet url: https://icastllp.com/material_db_pdf/ASTM%20B271%20Tin%20Bronze%20and%20Leaded%20Tin%20Bronze%20UNS%20C90500.pdf gaps: - Electrical conductivity and Brinell hardness are not names in property-canon.yaml, so the short names electrical_conductivity and hardness_brinell are used. - The coefficient of thermal expansion is printed only in exponent form (11 · 10 per °F and 19.8 · 10-6 per °C in the Concast table), so it is left out. - A MakeItFrom page for C90500 returned HTTP 403 and was not read, so no second modulus or density source is recorded; the 103400 MPa modulus is the only value. - No corrosion test data for C90500 were read. The only corrosion statement is a general gunmetal description in Wikipedia. - No space flight, outgassing, radiation or atomic oxygen data for any tin bronze were found in the sources used; this grade is not named in a space application in them. - No safety data sheet for C90500 was opened, so the lead hazard classification is not recorded. - The Concast PDF prints phosphorus in a column that does not align in the text extraction, so no phosphorus value is recorded. - The USGS tin summary text does not state whether tin is on the U.S. critical minerals list, so the tin critical_lists entry is empty. - Sand cast values (National Bronze) and continuous-cast minimum values (Concast) are different product forms and are kept as separate rows. - The National Bronze fatigue value (13 ksi, 90 MPa, typical) has no footnote text in the page, so it is not recorded. - The Wikipedia gunmetal melting point (about 1,000 degrees Celsius) and tensile range are for general gunmetal, not C90500, so they are not recorded. - The footnote markers (1), (2) and (3) in the Concast composition table have no printed text, so the exact definitions of Cu (min) and Ni (incl. Co) are taken from the table note only. sources: concast-c90500: title: C90500 datasheet, Wieland Concast (continuous-cast tin bronze; composition and mechanical properties per ASTM B505/B505M-23; physical properties from CDA) id: UNS C90500; ASTM B505, B22; SAE 62 url: https://www.concast.com/files/C90500.pdf kind: datasheet license: Manufacturer datasheet (cited, not reproduced) nationalbronze-c90500: title: C90500 (SAE62) Bronze, National Bronze and Metals id: SAE 62 url: https://nationalbronze.com/C90500_Gear_Bronze.php kind: datasheet license: Supplier datasheet (cited, not reproduced) concast-c90500-page: title: C90500 product page, Wieland Concast url: https://www.concast.com/c90500.php kind: web license: Manufacturer web page (cited, not reproduced) wikipedia-gunmetal: title: Gunmetal, Wikipedia url: https://en.wikipedia.org/wiki/Gunmetal kind: web license: CC BY-SA 4.0 (cited, not reproduced) usgs-tin-2026: title: Mineral Commodity Summaries 2026, Tin id: USGS MCS 2026 url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tin.pdf year: 2026 kind: report license: public domain (USGS) usgs-copper-2026: title: Mineral Commodity Summaries 2026, Copper id: USGS MCS 2026 url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf year: 2026 kind: report license: public domain (USGS) pubchem-cu: title: PubChem compound record for copper (CID 23978), including ECHA C&L Inventory classification id: CAS 7440-50-8, EC 231-159-6 url: https://pubchem.ncbi.nlm.nih.gov/compound/Copper kind: database license: PubChem (NCBI), public domain; sections attributed to ECHA and others icast-c90500: title: ASTM B271 Tin Bronze and Leaded Tin Bronze UNS C90500, ICAST Alloys LLP datasheet (centrifugal castings; composition, as-cast minimums and cross reference table) id: UNS C90500; ASTM B271, B505; SAE 62 url: https://icastllp.com/material_db_pdf/ASTM%20B271%20Tin%20Bronze%20and%20Leaded%20Tin%20Bronze%20UNS%20C90500.pdf kind: datasheet license: Supplier datasheet (cited, not reproduced) review: status: draft method: assistant checked_values: 16 unreachable: 1 caveats: 4 note: 'Values were read by an AI assistant on 2026-11-01 from the datasheets and USGS PDFs named in each entry (PDF text extracted with pdftotext). Unreachable: a MakeItFrom C90500 page (HTTP 403). Caveats: the Concast values are continuous-cast minimums and the National Bronze values are sand-cast typicals; the thermal conductivity unit is printed as W/m and read as W/(m·K); the tin and copper shares are calculated from printed tonnes.' license: CC-BY-4.0 updated: '2026-11-01' story: recipe: line: Tin bronze C90500 is a copper-tin-zinc casting alloy. Copper is the base metal, tin defines the bronze class, and zinc is a minor addition. The Concast datasheet covers the continuous-cast form, supplied as solids, tubes, rectangles and plate. parts: - name: Copper symbol: Cu share: 86.0 to 89.0 % (min to max), nominal 87.5 % role: The base metal and the largest share of the alloy. - name: Tin symbol: Sn share: 9.0 to 11.0 %, nominal 10.0 % role: Defines the tin bronze class; the alloy takes its tin-bronze name from this element. - name: Zinc symbol: Zn share: 1.0 to 3.0 %, nominal 2.0 % role: Minor addition printed in both the Concast composition table and the National Bronze nominal column. - name: Lead symbol: Pb share: 0.30 % maximum role: Impurity limit; the Concast table prints a single value, which it defines as a maximum. risk_groups: - title: For people level: 0 verdict: 'Copper-based alloy: handle dust and fume with care' lead: The alloy is mostly copper. Copper's GHS codes come from PubChem's aggregated company reports, and no safety data sheet for C90500 was read. points: - label: Copper content line: PubChem's copper record gives H302 at 21.7 % and H400 at 43.1 % of the company reports that gave hazard codes, and 52.5 % of all reports state copper does not meet GHS criteria. - label: Lead line: Lead is kept to a 0.30 % maximum in the composition table. - title: In the foundry level: 1 verdict: Hot metal between 854 and 999 °C lead: Melting and casting temperatures come from the Concast datasheet, which states the solidus and liquidus of the alloy. points: - label: Melting range line: The solidus is 854 °C and the liquidus is 999 °C, so the alloy is poured hot and freezes over a range. - label: Brazing line: Brazing is done within the hot-short range, so strain must be avoided during brazing and cooling. why: Tin bronze C90500 (SAE 62 gunmetal) is a copper-tin-zinc casting alloy with a density of 8.72 g/cm3 at 20 °C. In the continuous-cast form its minimum tensile strength is 303 MPa and its minimum yield strength is 172 MPa at 0.5 % extension under load. It is chosen where a strong, wear-resistant casting is needed for bushings, bearings and gears that carry heavy loads at low speed, and where resistance to steam and salt water matters. uses: - where: Gears, bushings and bearings line: Concast describes gear and high-strength bushing and bearing applications where high strength, low speeds and heavy loads are present. - where: Bridges and structures line: Concast lists movable bridge components and turntables for bridges, and structures for fixed and expansion bearings. - where: Electrical and plumbing parts line: The Concast typical-uses column lists electrical connectors, steam fittings and water conditioners. can_do: - label: Heavy loads at low speed benchmark: yield_strength value: 172 MPa line: 'Carry heavy loads at low speed as a bushing or bearing: the continuous-cast form has a minimum yield strength of 172 MPa at 0.5 % extension under load.' - label: Tensile strength benchmark: ultimate_tensile_strength value: 303 MPa line: Hold a minimum tensile strength of 303 MPa in the continuous-cast form, with a minimum elongation of 10 % in 2 in. or 50 mm. - label: Electrical conduction benchmark: electrical_conductivity value: 11 %IACS line: Conduct electricity at 11 %IACS (International Annealed Copper Standard, the reference scale for conductivity), so it is a poor conductor. - label: Corrosion resistance line: Resist corrosion from steam and salt water, according to a general gunmetal description (no C90500 test data were read). compare: Compared with pure copper in this collection, tin bronze C90500 gives up electrical and thermal conduction for strength and castability. Its electrical conductivity is 11 %IACS and its thermal conductivity is 74.8 W/(m·K) at 20 °C, while its continuous-cast minimum yield strength is 172 MPa. The table compares density, yield strength and modulus. compare_rows: - label: Density benchmark: density - label: Yield strength (continuous cast minimum) benchmark: yield_strength - label: Modulus of elasticity benchmark: elastic_modulus handling: - Keep strain off the part while brazing and cooling, because brazing is done inside the hot-short range. - Pour between the solidus of 854 °C and the liquidus of 999 °C, and plan feeding because solidification shrinkage is rated medium. - Treat the alloy as a copper product for any hazard assessment, because the copper classification from PubChem applies to its main constituent. good_for: - Bushings, bearings and gears under heavy loads at low speed, per the Concast uses section. - Castings that see steam or salt water, per the general gunmetal description in Wikipedia. watch_out: - Electrical conductivity is only 11 %IACS, so it is a poor choice for conductors. - The continuous-cast values are minimums and the sand-cast values are typicals; they are different forms and should not be mixed. - No space flight, outgassing or radiation data for this grade were found in the sources used. verdict: C90500 is a strong, corrosion-resistant bearing and gear bronze for heavy loads at low speed. Its space record is not documented in the sources used.