Solder & Low-Melting Alloy Bi32.5In51Sn16.5
Bi32.5In51Sn16.5 is a lead- and cadmium-free eutectic fusible alloy in the bismuth-indium-tin system, melting at about 62 °C and available as ingot, wire, shot, powder and as-cast parts.
Reference datasheet — Bi32.5In51Sn16.5 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the AS-CAST condition
Bi32.5In51Sn16.5 tempers and conditions
Bi32.5In51Sn16.5 is supplied in one standard condition, AS-CAST. AS-CAST is the default FabDigit quotes; the values on this page are for it.
Supply forms, finishes and certifications
Ways Bi32.5In51Sn16.5 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SHOT | Shot / pellets | Supply form |
WIRE | Extruded / drawn low-temperature solder wire | Supply form |
POWDER | Powder / paste-grade atomised powder | Printing process |
What is Bi32.5In51Sn16.5?
Bi32.5In51Sn16.5 is a lead- and cadmium-free eutectic fusible alloy in the bismuth-indium-tin system, melting at about 62 °C and available as ingot, wire, shot, powder and as-cast parts. It serves as a non-toxic substitute for Wood's metal in low-temperature casting and mould work, with 15 MPa tensile strength, 8 MPa yield, 100% elongation and 10 HB. Service is limited to roughly 40 °C and the alloy creeps under its own weight at room temperature; where a higher melt point is acceptable, Bi57Sn42Ag1 is the nearer alternative. Bi32.5In51Sn16.5 has a density of 7.88 g/cm³ (0.285 lb/in³), lighter than 60% of solder & low-melting alloy grades. It melts at 62°C (144 °F). Bi32.5In51Sn16.5 has a yield strength of 8 MPa (1.16 ksi) and a tensile strength of 15 MPa (2.18 ksi) — weaker than 93% of solder & low-melting alloy grades. Elongation at break is 100% and the elastic modulus is 10 GPa (1.45 Msi).
What is Bi32.5In51Sn16.5 used for?
- non-toxic fusible casting
- jewelry/pattern molding
- educational metal casting
- thermal fuses
Advantages
- Ductile — tolerates forming and impact — 100%, better than 100% of solder & low-melting alloy grades
- Good corrosion resistance — 55/100, better than 78% of solder & low-melting alloy grades
Limitations
- Low stiffness — 10 GPa (1.45 Msi), worse than 98% of solder & low-melting alloy grades
- Limited service temperature — 40°C (104 °F), worse than 97% of solder & low-melting alloy grades
- Low electrical conductivity — 3.4 % IACS, worse than 95% of solder & low-melting alloy grades
- High embodied carbon — 70 kg CO₂/kg, worse than 95% of solder & low-melting alloy grades
- Low strength — 8 MPa (1.16 ksi), worse than 93% of solder & low-melting alloy grades
Bi32.5In51Sn16.5 properties
Typical room-temperature values for Bi32.5In51Sn16.5-AS-CAST; bars are the position among solder & low-melting alloy grades.
Physical3
Bi32.5In51Sn16.5 has a density of 7.88 g/cm³ (0.285 lb/in³), lighter than 60% of solder & low-melting alloy grades. It melts at 62°C (144 °F).
Mechanical10
Bi32.5In51Sn16.5 has a yield strength of 8 MPa (1.16 ksi) and a tensile strength of 15 MPa (2.18 ksi) — weaker than 93% of solder & low-melting alloy grades. Elongation at break is 100% and the elastic modulus is 10 GPa (1.45 Msi).
Thermal6
Bi32.5In51Sn16.5 is rated for continuous service to 40°C (104 °F). It conducts heat at 19 W/m·K (11 BTU/hr·ft·°F), worse than 92% of solder & low-melting alloy grades. Thermal expansion is 23 µm/m·K (12.8 µin/in·°F).
Electrical3
Bi32.5In51Sn16.5 conducts electricity at 3.4 % IACS, worse than 95% of solder & low-melting alloy grades.
Chemical & Environmental2
Corrosion resistance is good (55/100), better than 78% of solder & low-melting alloy grades.
Sustainability3
Producing a kilogram of Bi32.5In51Sn16.5 takes about 1,100 MJ of energy and emits 70 kg of CO₂ — more than 96% of solder & low-melting alloy grades. Typical recycled content is 60%.
Manufacturability7
Bi32.5In51Sn16.5's machinability is poor (30/100, worse than 60% of solder & low-melting alloy grades); weldability poor (20/100); formability excellent (85/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the solder & low-melting alloy family
Yield strength against density for every solder & low-melting alloy grade FabDigit runs. Bi32.5In51Sn16.5 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Bi32.5In51Sn16.5
Is Bi32.5In51Sn16.5 easy to machine?
Machines only with sharp, high-rake tools, flood coolant and light cuts — the alloy smears and frictional heat can melt the chip; freezing the part or casting to net shape is usually preferred.
Can Bi32.5In51Sn16.5 be welded?
Not weldable in the normal sense; joints are made by remelting the alloy itself or by using it as the low-temperature solder — keep away from Al/Cu/Au parts that it would attack.
Can Bi32.5In51Sn16.5 be formed, bent or molded?
Ideal for gravity and open-mould casting at 80–100 °C in silicone, plaster or steel moulds; negligible shrinkage and excellent fill, but parts creep under their own load at room temperature.
Bi32.5In51Sn16.5 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. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Bieutectic composition | 32 – 33 | 32.5 |
| Sn | 16 – 17 | 16.5 |
| Pbimpurity limit — lead-free | ≤ 0.05 | |
| Cdimpurity limit — cadmium-free | ≤ 0.01 | |
| Inbalance; 51 wt% nominal | balance |
What surface finishes work on Bi32.5In51Sn16.5?
Cannot be anodised or plated conventionally; surfaces are simply cast-to-finish or lightly scraped, and a dull oxide film forms in humid air.
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy Bi32.5In51Sn16.5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- Field's Metal
How much does Bi32.5In51Sn16.5 cost?
Bi32.5In51Sn16.5 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Bi32.5In51Sn16.5 — frequently asked
What is Bi32.5In51Sn16.5 used for?
Bi32.5In51Sn16.5 is typically used for non-toxic fusible casting, jewelry/pattern molding, educational metal casting and thermal fuses. In short: melts at 62 °C; lead- and cadmium-free eutectic; highest ductility of family.
What is the yield strength of Bi32.5In51Sn16.5?
Bi32.5In51Sn16.5 has a typical yield strength of 8 MPa (1.16 ksi) and a tensile strength of 15 MPa (2.18 ksi) — weaker than 93% of solder & low-melting alloy grades.
Is Bi32.5In51Sn16.5 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 60% of solder & low-melting alloy grades). Machines only with sharp, high-rake tools, flood coolant and light cuts — the alloy smears and frictional heat can melt the chip; freezing the part or casting to net shape is usually preferred.
Can Bi32.5In51Sn16.5 be welded?
Not readily — weldability is rated poor (20/100). Not weldable in the normal sense; joints are made by remelting the alloy itself or by using it as the low-temperature solder — keep away from Al/Cu/Au parts that it would attack.
What surface finishes work on Bi32.5In51Sn16.5?
Cannot be anodised or plated conventionally; surfaces are simply cast-to-finish or lightly scraped, and a dull oxide film forms in humid air.
Can Bi32.5In51Sn16.5 be formed, bent or molded?
Ideal for gravity and open-mould casting at 80–100 °C in silicone, plaster or steel moulds; negligible shrinkage and excellent fill, but parts creep under their own load at room temperature.
What is the maximum service temperature of Bi32.5In51Sn16.5?
Bi32.5In51Sn16.5 is rated for continuous use to about 40°C (104 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Bi32.5In51Sn16.5 cost?
Bi32.5In51Sn16.5 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASM Handbook Vol. 3 — Alloy Phase Diagrams (Bi-In-Sn system) — ASM International (1992)
- Fusible / low-temperature alloy datasheets (Bi-In-Sn 62 °C eutectic) — Indium Corporation (2023)
- Field's Metal 62 °C low-melt alloy product data — Rotometals (2023)
- CRC Handbook of Chemistry and Physics — properties of Bi, In, Sn — CRC Press (2020)
- Bi-In-Sn eutectic phase-change / liquid-metal thermophysical property compilations — peer-reviewed literature (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.