Solder & Low-Melting Alloy Sn63Pb37Sb
Sn63Pb37Sb is the 183 °C tin-lead eutectic with a small antimony addition that raises strength and creep resistance in joints exposed to vibration or thermal cycling.
Reference datasheet — Sn63Pb37Sb 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.
Sn63Pb37Sb tempers and conditions
Sn63Pb37Sb is supplied in one standard condition, AS-SOLDERED.
Supply forms, finishes and certifications
Ways Sn63Pb37Sb is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
BARDefault | Cast bar / ingot for wave and dip soldering | Supply form |
CORED-WIRE | Flux-cored wire | Supply form |
PREFORM | Stamped washers, discs, rings and foil/ribbon | Supply form |
SPHERE | Solder balls / spheres for BGA and CSP ball attach | Supply form |
WIRE | Solid drawn/extruded wire | Supply form |
PASTE | Solder paste, Type 3/4 powder in no-clean or RMA flux | Printing process |
What is Sn63Pb37Sb?
Sn63Pb37Sb is the 183 °C tin-lead eutectic with a small antimony addition that raises strength and creep resistance in joints exposed to vibration or thermal cycling. Engineers choose it for mechanically stressed electrical connections; it is stocked as bar, solid and cored wire, paste, preforms and spheres, with as-soldered joint properties of 58 MPa tensile, 38 MPa yield, 32 % elongation and 16 HB. Service is capped near 100 °C, machinability is poor (score 20), and antimony makes it unsuitable against zinc-plated or cadmium-bearing surfaces. Plain Sn63Pb37 is the alternative where the extra creep strength is not needed. Sn63Pb37Sb has a density of 8.4 g/cm³ (0.303 lb/in³), lighter than 57% of solder & low-melting alloy grades. It melts at 183°C (361 °F). Sn63Pb37Sb has a yield strength of 38 MPa (5.51 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 85% of solder & low-melting alloy grades. Elongation at break is 32% and the elastic modulus is 32 GPa (4.64 Msi).
What is Sn63Pb37Sb used for?
- mechanically stressed electrical joints
- automotive wiring harness soldering
- terminal connections
Advantages
- High strength — 38 MPa (5.51 ksi), better than 85% of solder & low-melting alloy grades
Limitations
- Difficult to machine — 20/100, worse than 94% of solder & low-melting alloy grades
Sn63Pb37Sb properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
Sn63Pb37Sb has a density of 8.4 g/cm³ (0.303 lb/in³), lighter than 57% of solder & low-melting alloy grades. It melts at 183°C (361 °F).
Mechanical10
Sn63Pb37Sb has a yield strength of 38 MPa (5.51 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 85% of solder & low-melting alloy grades. Elongation at break is 32% and the elastic modulus is 32 GPa (4.64 Msi).
Thermal6
Sn63Pb37Sb is rated for continuous service to 100°C (212 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 63% of solder & low-melting alloy grades. Thermal expansion is 24.5 µm/m·K (13.6 µin/in·°F).
Electrical3
Sn63Pb37Sb conducts electricity at 11.5 % IACS, better than 71% 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 Sn63Pb37Sb takes about 210 MJ of energy and emits 11 kg of CO₂ — more than 57% of solder & low-melting alloy grades. Typical recycled content is 30%.
Manufacturability7
Sn63Pb37Sb's machinability is poor (20/100, worse than 94% 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. Sn63Pb37Sb is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Sn63Pb37Sb
Is Sn63Pb37Sb easy to machine?
Extremely soft and gummy — use sharp high-rake tools, flood lubricant and light cuts; solder is normally cast, extruded or stamped rather than machined.
Can Sn63Pb37Sb be welded?
Not fusion-welded; the alloy is itself the filler and is applied by wave, dip, iron, reflow or vapour-phase soldering at 210–250 °C peak.
Can Sn63Pb37Sb be formed, bent or molded?
Casts and extrudes easily at the 183 °C eutectic with a negligible pasty range; wire drawing and preform stamping need no intermediate anneal.
Sn63Pb37Sb 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 |
|---|---|---|
| Snnear-eutectic tin content | 62.5 – 63.5 | 63 |
| Sbstrengthening / anti-creep addition; some specs allow 0.12–0.50 | 0.2 – 0.5 | 0.35 |
| Biimpurity limit | ≤ 0.1 | |
| Cuimpurity limit | ≤ 0.05 | |
| Agimpurity limit | ≤ 0.05 | |
| Asimpurity limit | ≤ 0.03 | |
| Feimpurity limit | ≤ 0.02 | |
| Znimpurity limit (wetting) | ≤ 0 | |
| Alimpurity limit (wetting) | ≤ 0 | |
| Cdimpurity limit | ≤ 0 | |
| Pb | balance |
What surface finishes work on Sn63Pb37Sb?
Remove flux residues (IPA/saponifier or leave no-clean per IPC-610); avoid Zn-plated or Cd-bearing mating surfaces with Sb-bearing solder, and note RoHS restrictions on lead.
How much does Sn63Pb37Sb cost?
Sn63Pb37Sb is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sn63Pb37Sb — frequently asked
What is Sn63Pb37Sb used for?
Sn63Pb37Sb is typically used for mechanically stressed electrical joints, automotive wiring harness soldering and terminal connections. In short: creep-resistant leaded eutectic; strongest Sn63Pb37 variant; 183 °C eutectic melt.
What is the yield strength of Sn63Pb37Sb?
Sn63Pb37Sb has a typical yield strength of 38 MPa (5.51 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 85% of solder & low-melting alloy grades.
Is Sn63Pb37Sb easy to machine?
Not especially — machinability is rated poor (20/100, worse than 94% of solder & low-melting alloy grades). Extremely soft and gummy — use sharp high-rake tools, flood lubricant and light cuts; solder is normally cast, extruded or stamped rather than machined.
Can Sn63Pb37Sb be welded?
Not readily — weldability is rated poor (20/100). Not fusion-welded; the alloy is itself the filler and is applied by wave, dip, iron, reflow or vapour-phase soldering at 210–250 °C peak.
What surface finishes work on Sn63Pb37Sb?
Remove flux residues (IPA/saponifier or leave no-clean per IPC-610); avoid Zn-plated or Cd-bearing mating surfaces with Sb-bearing solder, and note RoHS restrictions on lead.
Can Sn63Pb37Sb be formed, bent or molded?
Casts and extrudes easily at the 183 °C eutectic with a negligible pasty range; wire drawing and preform stamping need no intermediate anneal.
What is the maximum service temperature of Sn63Pb37Sb?
Sn63Pb37Sb is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Sn63Pb37Sb cost?
Sn63Pb37Sb is a high-cost solder & low-melting alloy ($$$$), 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
- ISO 9453 — Soft solder alloys: chemical compositions and forms — ISO (2020)
- J-STD-006 — Requirements for Electronic Grade Solder Alloys — IPC (2013)
- GB/T 3131 (2020)
- ASM Handbook Vol.3 — Alloy Phase Diagrams / Soldering data — ASM International (1992)
- NIST Database for Solder Properties with Emphasis on New Lead-free Solders — NIST/Colorado School of Mines (2002)
- Sn63Pb37Sb solder bar / cored wire technical data — solder producers (AIM, Indium Corp., ) (2024)
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.