Solder & Low-Melting Alloy Bi50Pb25Sn12.5Cd12.5
also Cerrobend
Classic eutectic-like fusible alloy melting around 70°C, historically used for safety devices, fire sprinklers and pattern casting; contains toxic lead and cadmium so increasingly replaced by RoHS alternatives.
Reference datasheet — Bi50Pb25Sn12.5Cd12.5 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 Cast condition
Bi50Pb25Sn12.5Cd12.5 tempers and conditions
Bi50Pb25Sn12.5Cd12.5 is supplied in 2 conditions, soft to hard. Cast is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
CastDefault As cast | Standard condition: melt at 80–100 °C and pour into the tube, fixture or mould; measure/use within hours before age growth. | 26 | 44 | 50 | 10 HB | 3.2 % IACS |
Cast and age-stabilised (held ~30 days at room temperature) | Pick when dimensional stability matters: the bismuth-rich alloy grows slightly for weeks after casting, so masters and gauge fillers are aged before final machining. | 30 | 48 | 30 | 12 HB | 3.2 % IACS |
Supply forms, finishes and certifications
Ways Bi50Pb25Sn12.5Cd12.5 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Ingot | Ingot / bar stock for remelting | Supply form |
WIRE | Extruded wire / rod | Supply form |
What is Bi50Pb25Sn12.5Cd12.5?
Classic eutectic-like fusible alloy melting around 70°C, historically used for safety devices, fire sprinklers and pattern casting; contains toxic lead and cadmium so increasingly replaced by RoHS alternatives. Bi50Pb25Sn12.5Cd12.5 has a density of 9.6 g/cm³ (0.347 lb/in³), heavier than 66% of solder & low-melting alloy grades. It melts at 70°C (158 °F). Bi50Pb25Sn12.5Cd12.5 has a yield strength of 26 MPa (3.77 ksi) and a tensile strength of 44 MPa (6.38 ksi) — weaker than 55% of solder & low-melting alloy grades. Elongation at break is 50% and the elastic modulus is 10 GPa (1.45 Msi).
What is Bi50Pb25Sn12.5Cd12.5 used for?
- fire sprinkler fusible links
- safety plugs
- pattern/mold making
- metal casting demonstrations
- temperature fuses
Advantages
- Ductile — tolerates forming and impact — 50%, better than 92% 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 — 3.2 % IACS, worse than 97% of solder & low-melting alloy grades
- Poor heat conductor — 18.8 W/m·K (10.9 BTU/hr·ft·°F), worse than 94% of solder & low-melting alloy grades
Bi50Pb25Sn12.5Cd12.5 properties
Typical room-temperature values for Bi50Pb25Sn12.5Cd12.5-Cast; bars are the position among solder & low-melting alloy grades.
Physical3
Bi50Pb25Sn12.5Cd12.5 has a density of 9.6 g/cm³ (0.347 lb/in³), heavier than 66% of solder & low-melting alloy grades. It melts at 70°C (158 °F).
Mechanical11
Bi50Pb25Sn12.5Cd12.5 has a yield strength of 26 MPa (3.77 ksi) and a tensile strength of 44 MPa (6.38 ksi) — weaker than 55% of solder & low-melting alloy grades. Elongation at break is 50% and the elastic modulus is 10 GPa (1.45 Msi).
Thermal6
Bi50Pb25Sn12.5Cd12.5 is rated for continuous service to 40°C (104 °F). It conducts heat at 18.8 W/m·K (10.9 BTU/hr·ft·°F), worse than 94% of solder & low-melting alloy grades. Thermal expansion is 24 µm/m·K (13.3 µin/in·°F).
Electrical3
Bi50Pb25Sn12.5Cd12.5 conducts electricity at 3.2 % IACS, worse than 97% of solder & low-melting alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 82% of solder & low-melting alloy grades.
Sustainability4
Producing a kilogram of Bi50Pb25Sn12.5Cd12.5 takes about 92 MJ of energy and emits 6.5 kg of CO₂ — less than 72% of solder & low-melting alloy grades. Typical recycled content is 70%.
Manufacturability8
Bi50Pb25Sn12.5Cd12.5's machinability is fair (45/100, better than 69% of solder & low-melting alloy grades); weldability poor (15/100); formability very good (70/100).
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. Bi50Pb25Sn12.5Cd12.5 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Bi50Pb25Sn12.5Cd12.5
Is Bi50Pb25Sn12.5Cd12.5 easy to machine?
Machines like soft lead — very sharp positive-rake tools, light cuts, flood coolant to keep the part below ~40 °C, and expect smearing rather than chips.
Can Bi50Pb25Sn12.5Cd12.5 be welded?
Not fusion-welded in the usual sense; joints are made by remelting the alloy itself at 80–100 °C, and it wets clean steel, brass and copper readily with rosin flux.
Can Bi50Pb25Sn12.5Cd12.5 be formed, bent or molded?
Best used as a casting alloy: melt in a water- or oil-jacketed pot at 80–100 °C (never above ~200 °C, cadmium fume), pour into warmed silicone/steel moulds; near-zero shrinkage gives sharp replication.
Bi50Pb25Sn12.5Cd12.5 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 |
|---|---|---|
| PbRoHS-restricted | 24 – 26 | 25 |
| Sn | 12 – 13 | 12.5 |
| CdRoHS-restricted; toxic fume hazard on overheating | 12 – 13 | 12.5 |
| Others (each)impurities Cu, Zn, Fe, Sb typically <0.05 % each | ≤ 0.05 | |
| Bibalance bismuth | ≥ 49 (balance) |
What surface finishes work on Bi50Pb25Sn12.5Cd12.5?
No plating or anodizing; surfaces are left as-cast or burnished, and parts should be washed and handled with gloves because of lead/cadmium contamination.
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy Bi50Pb25Sn12.5Cd12.5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Cerrobend
- Also called
- Wood's Metal
How much does Bi50Pb25Sn12.5Cd12.5 cost?
Bi50Pb25Sn12.5Cd12.5 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.
Bi50Pb25Sn12.5Cd12.5 — frequently asked
What is Bi50Pb25Sn12.5Cd12.5 used for?
Bi50Pb25Sn12.5Cd12.5 is typically used for fire sprinkler fusible links, safety plugs, pattern/mold making, metal casting demonstrations and temperature fuses. In short: 70 °C melting point; near-zero casting shrinkage; contains lead and cadmium.
What is the yield strength of Bi50Pb25Sn12.5Cd12.5?
Bi50Pb25Sn12.5Cd12.5 has a typical yield strength of 26 MPa (3.77 ksi) and a tensile strength of 44 MPa (6.38 ksi) — weaker than 55% of solder & low-melting alloy grades. Strength varies by condition: see the 2 listed tempers.
Is Bi50Pb25Sn12.5Cd12.5 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 69% of solder & low-melting alloy grades). Machines like soft lead — very sharp positive-rake tools, light cuts, flood coolant to keep the part below ~40 °C, and expect smearing rather than chips.
Can Bi50Pb25Sn12.5Cd12.5 be welded?
Not readily — weldability is rated poor (15/100). Not fusion-welded in the usual sense; joints are made by remelting the alloy itself at 80–100 °C, and it wets clean steel, brass and copper readily with rosin flux.
What surface finishes work on Bi50Pb25Sn12.5Cd12.5?
No plating or anodizing; surfaces are left as-cast or burnished, and parts should be washed and handled with gloves because of lead/cadmium contamination.
Can Bi50Pb25Sn12.5Cd12.5 be formed, bent or molded?
Best used as a casting alloy: melt in a water- or oil-jacketed pot at 80–100 °C (never above ~200 °C, cadmium fume), pour into warmed silicone/steel moulds; near-zero shrinkage gives sharp replication.
What is the maximum service temperature of Bi50Pb25Sn12.5Cd12.5?
Bi50Pb25Sn12.5Cd12.5 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 Bi50Pb25Sn12.5Cd12.5 cost?
Bi50Pb25Sn12.5Cd12.5 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. 2 — Properties and Selection: Nonferrous Alloys, Low-Melting (Fusible) Alloys — ASM International (1990)
- ASTM B774 — Standard Specification for Low Melting Point Alloys — ASTM International (2016)
- Fusible alloy technical data (Cerrobend / 158 °F alloy) — Cerro / Indium Corporation (2022)
- Bi-Pb-Sn-Cd eutectic thermophysical data — CRC Handbook of Chemistry and Physics (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.