Solder & Low-Melting Alloy Sn70Pb30
ASTM Sn70 · JIS H70A, Z3282 H70A · GB HLSnPb70-30
Sn70Pb30 (H70A, HLSnPb70-30, Z3282 H70A) is a tin-rich Sn-Pb solder sitting above the 63/37 eutectic, so it freezes over a 183–192 °C pasty range rather than at a single point.
Reference datasheet — Sn70Pb30 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.
Sn70Pb30 tempers and conditions
Sn70Pb30 is supplied in 2 conditions, soft to hard.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Low-antimony grade | Pick where antimony must be kept low (zinc/galvanized or cadmium-plated substrates, some electronics specs). | 30 | 46 | 40 | 14 HB | 12.3 % IACS |
Antimonial grade | Pick for slightly higher strength and creep resistance on plain copper/steel; avoid on zinc or cadmium coatings. | 35 | 52 | 32 | 16 HB | 11.8 % IACS |
Supply forms, finishes and certifications
Ways Sn70Pb30 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FOIL | Foil / preform / ribbon | Supply form |
IngotDefault | Ingot / solid bar | Supply form |
WIRE | Solid wire | Supply form |
WIRE-CORED | Flux-cored wire | Supply form |
PASTE | Solder paste | Printing process |
What is Sn70Pb30?
Sn70Pb30 (H70A, HLSnPb70-30, Z3282 H70A) is a tin-rich Sn-Pb solder sitting above the 63/37 eutectic, so it freezes over a 183–192 °C pasty range rather than at a single point. The slower solidification aids wetting on difficult or oxidised surfaces, and the alloy is supplied as ingot, solid and flux-cored wire, foil and paste. Strength is low (47 MPa tensile, 30 MPa yield, 40 % elongation, 14 HB) and the lead content restricts use under RoHS and potable-water rules. Sn63Pb37 is the alternative where a sharp eutectic freeze is wanted, and SAC0307 where lead-free is mandatory. Sn70Pb30 has a density of 8.17 g/cm³ (0.295 lb/in³), lighter than 59% of solder & low-melting alloy grades. It melts at 183°C (361 °F). Sn70Pb30 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 47 MPa (6.82 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 30 GPa (4.35 Msi).
What is Sn70Pb30 used for?
- general purpose soldering
- sheet metal joining
- radiator repair
Advantages
- High electrical conductivity — 12.3 % IACS, better than 80% of solder & low-melting alloy grades
Limitations
- Needs corrosion protection — 35/100, worse than 94% of solder & low-melting alloy grades
- Difficult to weld — 10/100, worse than 94% of solder & low-melting alloy grades
- Hard to polish — 20/100, worse than 88% of solder & low-melting alloy grades
Sn70Pb30 properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
Sn70Pb30 has a density of 8.17 g/cm³ (0.295 lb/in³), lighter than 59% of solder & low-melting alloy grades. It melts at 183°C (361 °F).
Mechanical10
Sn70Pb30 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 47 MPa (6.82 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 30 GPa (4.35 Msi).
Thermal6
Sn70Pb30 is rated for continuous service to 100°C (212 °F). It conducts heat at 52 W/m·K (30 BTU/hr·ft·°F), better than 72% of solder & low-melting alloy grades. Thermal expansion is 24 µm/m·K (13.3 µin/in·°F).
Electrical3
Sn70Pb30 conducts electricity at 12.3 % IACS, better than 80% of solder & low-melting alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (35/100), worse than 94% of solder & low-melting alloy grades.
Sustainability4
Producing a kilogram of Sn70Pb30 takes about 190 MJ of energy and emits 12 kg of CO₂ — more than 50% of solder & low-melting alloy grades. Typical recycled content is 30%.
Manufacturability6
Sn70Pb30's machinability is poor (30/100, worse than 60% of solder & low-melting alloy grades); weldability not recommended (10/100); formability excellent (95/100).
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. Sn70Pb30 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Sn70Pb30
Is Sn70Pb30 easy to machine?
Very soft and gummy — use sharp high-rake tools, high speed, low feed and paraffin/kerosene lube; parts smear and load abrasives, so cast or extrude to shape instead.
Can Sn70Pb30 be welded?
Not arc-weldable; joints are made by remelting the solder itself (iron, wave, dip or reflow) at 230–260 °C with rosin or activated flux.
Can Sn70Pb30 be formed, bent or molded?
Freely extruded into wire and rolled into foil at room temperature; casts easily into bars/ingots at 250–280 °C — avoid moving joints while in the 183–192 °C pasty range or fillets become grainy and disturbed.
Sn70Pb30 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 |
|---|---|---|
| Sntin, primary constituent | 69.5 – 71.5 | 70 |
| Sb0.20–0.50 % in the antimonial 'B' grade | ≤ 0.12 | 0.05 |
| Cuimpurity limit | ≤ 0.08 | 0.03 |
| Biimpurity limit | ≤ 0.25 | 0.05 |
| Asimpurity limit | ≤ 0.03 | 0.01 |
| Feimpurity limit | ≤ 0.02 | 0.01 |
| Znimpurity limit — degrades wetting | ≤ 0.01 | 0 |
| Alimpurity limit — degrades wetting | ≤ 0.01 | 0 |
| Cdimpurity limit | ≤ 0.01 | 0 |
| Agimpurity limit | ≤ 0.05 | 0.01 |
| Pb | balance |
What surface finishes work on Sn70Pb30?
No plating or anodizing; keep flux residues cleaned off (saponifier or IPA) to prevent white corrosion, and handle as a lead-bearing material with RoHS/potable-water restrictions.
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy Sn70Pb30 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- Sn70
- GB (China)
- HLSnPb70-30
- JIS
- H70AZ3282 H70A
- Also called
- 70/30 solder
How much does Sn70Pb30 cost?
Sn70Pb30 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sn70Pb30 — frequently asked
What is Sn70Pb30 used for?
Sn70Pb30 is typically used for general purpose soldering, sheet metal joining and radiator repair. In short: tin-rich Sn-Pb solder; wider pasty range than eutectic; good wetting on oxidised surfaces.
What is the yield strength of Sn70Pb30?
Sn70Pb30 has a typical yield strength of 30 MPa (4.35 ksi) and a tensile strength of 47 MPa (6.82 ksi) — stronger than 61% of solder & low-melting alloy grades. Strength varies by condition: see the 2 listed tempers.
Is Sn70Pb30 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 60% of solder & low-melting alloy grades). Very soft and gummy — use sharp high-rake tools, high speed, low feed and paraffin/kerosene lube; parts smear and load abrasives, so cast or extrude to shape instead.
Can Sn70Pb30 be welded?
Not readily — weldability is rated not recommended (10/100). Not arc-weldable; joints are made by remelting the solder itself (iron, wave, dip or reflow) at 230–260 °C with rosin or activated flux.
What surface finishes work on Sn70Pb30?
No plating or anodizing; keep flux residues cleaned off (saponifier or IPA) to prevent white corrosion, and handle as a lead-bearing material with RoHS/potable-water restrictions.
Can Sn70Pb30 be formed, bent or molded?
Freely extruded into wire and rolled into foil at room temperature; casts easily into bars/ingots at 250–280 °C — avoid moving joints while in the 183–192 °C pasty range or fillets become grainy and disturbed.
What is the maximum service temperature of Sn70Pb30?
Sn70Pb30 is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Sn70Pb30 cost?
Sn70Pb30 is a high-cost solder & low-melting alloy ($$$$), 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)
- J-STD-006 — Requirements for Electronic Grade Solder Alloys — IPC (2013)
- JIS Z 3282 — Soft solders (H70A) — JSA (2017)
- GB/T 3131 — (HLSnPb70-30) (2020)
- ASM Handbook Vol. 3 — Alloy Phase Diagrams (Sn-Pb) — ASM International (1992)
- ASM Handbook Vol. 2 — Properties of Solders and Low-Melting Alloys — ASM International (1990)
- Sn-Pb solder alloy data (bar, wire, paste) — 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.