Solder & Low-Melting Alloy Sn99.9 Cast
Grade
ASTM B339 Grade A · JIS H2112 Sn99.9
Cast = as cast
Pick for cast tin anodes, tinning bar and decorative castings where no mechanical duty is required.
Values for the Cast condition
Other Sn99.9 tempers and conditions
Sn99.9 is listed in 3 conditions; see the grade overview at Sn99.9.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
CastThis page As cast | Pick for cast tin anodes, tinning bar and decorative castings where no mechanical duty is required. | 8 | 14 | 40 | 4 HB | 15 % IACS |
Annealed | Fully soft condition (which pure tin reverts to at room temperature anyway) for maximum ductility in forming and wrapping. | 8 | 15 | 60 | 4 HB | 15 % IACS |
Cold rolled | Rolled sheet, strip and foil for gaskets, capacitor foil, organ pipes and lining; tin self-anneals at room temperature so 'hard' tempers are not stable. | 11 | 20 | 55 | 5 HB | 15 % IACS |
What is Sn99.9 Cast?
Sn99.9 Cast is Sn99.9 in the Cast grade — pick for cast tin anodes, tinning bar and decorative castings where no mechanical duty is required. Sn99.9 Cast has a yield strength of 8 MPa (1.16 ksi) and a tensile strength of 14 MPa (2.03 ksi) — weaker than 93% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 44 GPa (6.38 Msi). Sn99.9 Cast has a density of 7.29 g/cm³ (0.263 lb/in³), lighter than 96% of solder & low-melting alloy grades. It melts at 232°C (449 °F).
Advantages
- Conducts heat well — 66.6 W/m·K (38.5 BTU/hr·ft·°F), better than 98% of solder & low-melting alloy grades
- High electrical conductivity — 15 % IACS, better than 97% of solder & low-melting alloy grades
- Lightweight — 7.29 g/cm³ (0.263 lb/in³), better than 96% of solder & low-melting alloy grades
- Good corrosion resistance — 65/100, better than 96% of solder & low-melting alloy grades
- Polishes to a fine finish — 70/100, better than 91% of solder & low-melting alloy grades
Limitations
- Low strength — 8 MPa (1.16 ksi), worse than 93% of solder & low-melting alloy grades
- High embodied carbon — 18 kg CO₂/kg, worse than 76% of solder & low-melting alloy grades
Sn99.9 Cast properties
Typical room-temperature values for Sn99.9 Cast; 18 are specific to this condition. Other listed values are Sn99.9 reference data and may not represent this condition. Bars are the position among solder & low-melting alloy grades.
Physical3
Sn99.9 Cast has a density of 7.29 g/cm³ (0.263 lb/in³), lighter than 96% of solder & low-melting alloy grades. It melts at 232°C (449 °F).
Mechanical10
Sn99.9 Cast has a yield strength of 8 MPa (1.16 ksi) and a tensile strength of 14 MPa (2.03 ksi) — weaker than 93% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 44 GPa (6.38 Msi).
Thermal6
Sn99.9 Cast is rated for continuous service to 100°C (212 °F). It conducts heat at 66.6 W/m·K (38.5 BTU/hr·ft·°F), better than 98% of solder & low-melting alloy grades. Thermal expansion is 23 µm/m·K (12.8 µin/in·°F).
Electrical3
Sn99.9 Cast conducts electricity at 15 % IACS, better than 97% of solder & low-melting alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 96% of solder & low-melting alloy grades.
Sustainability4
Producing a kilogram of Sn99.9 Cast takes about 320 MJ of energy and emits 18 kg of CO₂ — more than 81% of solder & low-melting alloy grades. Typical recycled content is 30%.
Manufacturability8
Sn99.9 Cast's machinability is fair (45/100, better than 69% of solder & low-melting alloy grades); weldability fair (40/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Sn99.9 Cast
Is Sn99.9 easy to machine?
Very soft and gummy — use sharp high-rake tools, high speed, light feed and generous lubrication or freeze/chill the part to avoid smearing.
Can Sn99.9 be welded?
Rarely fusion welded; joints are made by soldering or by simply remelting since the metal itself is the solder base — keep away from sulfur and avoid overheating (dross formation).
Can Sn99.9 be formed, bent or molded?
Rolls to foil and cold-forms almost without limit because it recrystallizes at room temperature; casts easily at 250–300 °C with low shrinkage but poor as-cast strength.
What surface finishes work on Sn99.9?
Bright but easily scratched; can be burnished, tumbled or lightly buffed. Not anodizable; typically used as-plated/tinned or given a light passivation to avoid dulling and whisker growth.
Sn99.9 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance.
| Element | Spec limit (wt %) |
|---|---|
| Pbimpurity limit | ≤ 0.05 |
| Sbimpurity limit | ≤ 0.05 |
| Biimpurity limit | ≤ 0.03 |
| Asimpurity limit | ≤ 0.03 |
| Cuimpurity limit | ≤ 0.03 |
| Feimpurity limit | ≤ 0.01 |
| Znimpurity limit | ≤ 0 |
| Alimpurity limit | ≤ 0 |
| Cdimpurity limit | ≤ 0 |
| Simpurity limit | ≤ 0.01 |
| Total impuritiessum of impurities | ≤ 0.1 |
| SnGB/T 728 Sn99.90 / ASTM B339 Grade A | ≥ 99.9 (balance) |
Sn99.9 Cast — frequently asked
What is Sn99.9 Cast used for?
Sn99.9 Cast is typically used for alloy feedstock, tin plating anodes, chemical tin salts and babbitt/pewter melting stock. In short: purest tin feedstock; corrosion-resistant, low melting point; softest alloy in the family.
What is the yield strength of Sn99.9 Cast?
Sn99.9 Cast has a typical yield strength of 8 MPa (1.16 ksi) and a tensile strength of 14 MPa (2.03 ksi) — weaker than 93% of solder & low-melting alloy grades. Strength varies by condition: see the 3 listed tempers.
Is Sn99.9 Cast easy to machine?
Reasonably — machinability is rated fair (45/100, better than 69% of solder & low-melting alloy grades). Very soft and gummy — use sharp high-rake tools, high speed, light feed and generous lubrication or freeze/chill the part to avoid smearing.
Can Sn99.9 Cast be welded?
With care — weldability is rated fair (40/100). Rarely fusion welded; joints are made by soldering or by simply remelting since the metal itself is the solder base — keep away from sulfur and avoid overheating (dross formation).
What surface finishes work on Sn99.9 Cast?
Bright but easily scratched; can be burnished, tumbled or lightly buffed. Not anodizable; typically used as-plated/tinned or given a light passivation to avoid dulling and whisker growth.
Can Sn99.9 Cast be formed, bent or molded?
Rolls to foil and cold-forms almost without limit because it recrystallizes at room temperature; casts easily at 250–300 °C with low shrinkage but poor as-cast strength.
What is the maximum service temperature of Sn99.9 Cast?
Sn99.9 Cast is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- GB/T 728 — SAC (2020)
- ASTM B339 Standard Specification for Pig Tin — ASTM International (2022)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Tin and Tin Alloys) — ASM International (1990)
- CRC Handbook of Chemistry and Physics — Properties of the Elements — CRC Press (2022)
- International Tin Association / ITRI tin property data — ITA (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.