Solder & Low-Melting Alloy Sn50Pb50
ASTM Sn50 · JIS H50A · GB HLSnPb50-50
Sn50Pb50 (H50A, HLSnPb50-50) is a mid-tin lead-bearing solder whose broad 183–216 °C pasty range gives a long plastic stage that suits wiped and swept joints.
Reference datasheet — Sn50Pb50 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.
What is Sn50Pb50?
Sn50Pb50 (H50A, HLSnPb50-50) is a mid-tin lead-bearing solder whose broad 183–216 °C pasty range gives a long plastic stage that suits wiped and swept joints. It is the traditional plumbing, sheet-metal and radiator alloy, supplied as bar, solid wire, rosin- and acid-cored wire, foil, preforms and paste. Mechanical values are modest (42 MPa tensile, 45 % elongation, 14 HB), and the alloy is not permitted on potable-water or RoHS parts. Sn70Pb30 or eutectic Sn-Pb give faster freezing for electrical work, while SAC grades replace it where lead-free legislation applies. Sn50Pb50 has a density of 8.87 g/cm³ (0.32 lb/in³), heavier than 57% of solder & low-melting alloy grades. It melts at 183°C (361 °F). Sn50Pb50 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 42 MPa (6.09 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 45% and the elastic modulus is 27 GPa (3.92 Msi).
What is Sn50Pb50 used for?
- plumbing joints
- sheet metal seaming
- radiator manufacturing
Advantages
- Ductile — tolerates forming and impact — 45%, better than 84% of solder & low-melting alloy grades
Sn50Pb50 properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
Sn50Pb50 has a density of 8.87 g/cm³ (0.32 lb/in³), heavier than 57% of solder & low-melting alloy grades. It melts at 183°C (361 °F).
Mechanical12
Sn50Pb50 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 42 MPa (6.09 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 45% and the elastic modulus is 27 GPa (3.92 Msi).
Thermal6
Sn50Pb50 is rated for continuous service to 100°C (212 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 55% of solder & low-melting alloy grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
Sn50Pb50 conducts electricity at 10.9 % IACS, better than 63% of solder & low-melting alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 52% of solder & low-melting alloy grades.
Sustainability4
Producing a kilogram of Sn50Pb50 takes about 170 MJ of energy and emits 9.5 kg of CO₂ — less than 56% of solder & low-melting alloy grades. Typical recycled content is 40%.
Manufacturability6
Sn50Pb50's machinability is poor (25/100, worse than 82% of solder & low-melting alloy grades); weldability poor (20/100); formability excellent (90/100).
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. Sn50Pb50 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Sn50Pb50
Is Sn50Pb50 easy to machine?
Very soft and gummy — use sharp high-rake tools, low speed and paraffin/kerosene lube; solder is normally cast or extruded to shape rather than machined.
Can Sn50Pb50 be welded?
Not fusion welded; the alloy is a filler metal — joints are made by soldering at 230–260 °C with rosin (electrical) or acid/ZnCl2 (sheet metal, non-potable plumbing) flux.
Can Sn50Pb50 be formed, bent or molded?
Extrudes and rolls easily at room temperature into wire, ribbon and preforms; the wide 183–216 °C pasty range makes it ideal for wiped and swept joints.
Sn50Pb50 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 |
|---|---|---|
| SnASTM B32 alloy grade Sn50 | 49.5 – 51.5 | 50 |
| Sbgrade Sn50A; antimonial grade Sn50B allows 0.20–0.50 % | ≤ 0.12 | 0.05 |
| Biimpurity limit | ≤ 0.25 | |
| Cuimpurity limit | ≤ 0.08 | |
| Agimpurity limit (non-silver-bearing grade) | ≤ 0.02 | |
| Feimpurity limit | ≤ 0.02 | |
| Asimpurity limit | ≤ 0.03 | |
| Znimpurity limit | ≤ 0.01 | |
| Alimpurity limit | ≤ 0.01 | |
| Cdimpurity limit | ≤ 0 | |
| Pb | balance |
What surface finishes work on Sn50Pb50?
Wipe or wire-brush hot; wash off activated flux residues to prevent corrosion; do not plate or anodize — surface dulls to a grey oxide that is cosmetically stable.
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy Sn50Pb50 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- Sn50
- GB (China)
- HLSnPb50-50
- JIS
- H50A
How much does Sn50Pb50 cost?
Sn50Pb50 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sn50Pb50 — frequently asked
What is Sn50Pb50 used for?
Sn50Pb50 is typically used for plumbing joints, sheet metal seaming and radiator manufacturing. In short: classic wiping solder; long plastic freezing range; sheet-metal and plumbing grade.
What is the yield strength of Sn50Pb50?
Sn50Pb50 has a typical yield strength of 30 MPa (4.35 ksi) and a tensile strength of 42 MPa (6.09 ksi) — stronger than 61% of solder & low-melting alloy grades.
Is Sn50Pb50 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 82% of solder & low-melting alloy grades). Very soft and gummy — use sharp high-rake tools, low speed and paraffin/kerosene lube; solder is normally cast or extruded to shape rather than machined.
Can Sn50Pb50 be welded?
Not readily — weldability is rated poor (20/100). Not fusion welded; the alloy is a filler metal — joints are made by soldering at 230–260 °C with rosin (electrical) or acid/ZnCl2 (sheet metal, non-potable plumbing) flux.
What surface finishes work on Sn50Pb50?
Wipe or wire-brush hot; wash off activated flux residues to prevent corrosion; do not plate or anodize — surface dulls to a grey oxide that is cosmetically stable.
Can Sn50Pb50 be formed, bent or molded?
Extrudes and rolls easily at room temperature into wire, ribbon and preforms; the wide 183–216 °C pasty range makes it ideal for wiped and swept joints.
What is the maximum service temperature of Sn50Pb50?
Sn50Pb50 is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Sn50Pb50 cost?
Sn50Pb50 is a high-cost solder & low-melting alloy ($$$$), 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
- ASTM B32 — Standard Specification for Solder Metal — ASTM International (2020)
- GB/T 3131 (2020)
- J-STD-006 — Requirements for Electronic Grade Solder Alloys — IPC (2013)
- ASM Handbook Vol. 6 — Welding, Brazing, and Soldering (Solder alloy properties) — ASM International (1993)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Tin and Lead alloys) — ASM International (1990)
- Sn50Pb50 solder bar/wire technical data — AIM Solder / Indium Corporation (2023)
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.