Solder & Low-Melting Alloy B23 Grade 8
ASTM B23 Grade 8 · UNS L53565
ASTM B23 Grade 8 is a lead-base white-metal bearing alloy (babbitt) with roughly 7.5–8.5% Sb, 3.5–4.5% Sn and 0.3–0.7% Cu, balance Pb, covered by ASTM B23 and UNS L53565.
Reference datasheet — B23 Grade 8 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.
B23 Grade 8 tempers and conditions
B23 Grade 8 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 |
|---|---|---|---|---|---|---|
Static (gravity) cast lining on steel/bronze shell | Choose for large, thick-wall bearings and field re-babbitting where slow solidification is acceptable. | 22 | 50 | 2.5 | 19 HB | 5.6 % IACS |
Chill-cast test specimen | Reference condition in which the published ASTM B23 hardness and compressive data are measured. | 23 | 55 | 3 | 20 HB | 5.6 % IACS |
Supply forms, finishes and certifications
Ways B23 Grade 8 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
IngotDefault | As-cast remelt ingot per ASTM B23 | Supply form |
CC | Centrifugally cast lining | Surface finish |
What is B23 Grade 8?
ASTM B23 Grade 8 is a lead-base white-metal bearing alloy (babbitt) with roughly 7.5–8.5% Sb, 3.5–4.5% Sn and 0.3–0.7% Cu, balance Pb, covered by ASTM B23 and UNS L53565. Its low tin content makes it the economical lining for lightly to moderately loaded plain bearings, supplied as ingot for sand, centrifugal or chill casting onto steel shells. Strength is 55 MPa tensile at 3% elongation and 20 HB, so it suits low-speed, low-load service rather than high-speed turbomachinery, where a tin-base babbitt is used instead. Lead content brings RoHS/REACH restrictions. B23 Grade 8 has a density of 10.04 g/cm³ (0.363 lb/in³), heavier than 77% of solder & low-melting alloy grades. It melts at 240°C (464 °F). B23 Grade 8 has a yield strength of 26 MPa (3.77 ksi) and a tensile strength of 55 MPa (7.98 ksi) — weaker than 55% of solder & low-melting alloy grades. Elongation at break is 3% and the elastic modulus is 29 GPa (4.21 Msi).
What is B23 Grade 8 used for?
- General purpose plain bearings
- Pump and motor bushings
- Low-speed shaft bearings
- Bearing re-babbitting/repair
Advantages
- Easy to machine — 90/100, better than 95% of solder & low-melting alloy grades
- Low embodied carbon — 2.2 kg CO₂/kg, better than 88% of solder & low-melting alloy grades
- Polishes to a fine finish — 60/100, better than 82% of solder & low-melting alloy grades
Limitations
- Limited ductility — 3%, worse than 95% of solder & low-melting alloy grades
- Limited formability — 25/100, worse than 91% of solder & low-melting alloy grades
- Low electrical conductivity — 5.6 % IACS, worse than 88% of solder & low-melting alloy grades
- Poor heat conductor — 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 86% of solder & low-melting alloy grades
- Heavy — 10.04 g/cm³ (0.363 lb/in³), worse than 77% of solder & low-melting alloy grades
B23 Grade 8 properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
B23 Grade 8 has a density of 10.04 g/cm³ (0.363 lb/in³), heavier than 77% of solder & low-melting alloy grades. It melts at 240°C (464 °F).
Mechanical11
B23 Grade 8 has a yield strength of 26 MPa (3.77 ksi) and a tensile strength of 55 MPa (7.98 ksi) — weaker than 55% of solder & low-melting alloy grades. Elongation at break is 3% and the elastic modulus is 29 GPa (4.21 Msi).
Thermal6
B23 Grade 8 is rated for continuous service to 120°C (248 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 86% of solder & low-melting alloy grades. Thermal expansion is 26 µm/m·K (14.4 µin/in·°F).
Electrical3
B23 Grade 8 conducts electricity at 5.6 % IACS, worse than 88% 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 B23 Grade 8 takes about 28 MJ of energy and emits 2.2 kg of CO₂ — less than 89% of solder & low-melting alloy grades. Typical recycled content is 70%.
Manufacturability8
B23 Grade 8's machinability is excellent (90/100, better than 95% of solder & low-melting alloy grades); weldability poor (20/100); formability poor (25/100).
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. B23 Grade 8 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with B23 Grade 8
Is B23 Grade 8 easy to machine?
Bores and scrapes very easily with sharp, high-rake tools and generous clearance; use light cuts, flood coolant to avoid smearing, and capture lead-bearing swarf per occupational hygiene rules.
Can B23 Grade 8 be welded?
Not arc-weldable; repair by torch build-up with matching babbitt filler or by stripping and re-pouring the lining.
Can B23 Grade 8 be formed, bent or molded?
Cast only — degas and skim the melt, tin the steel shell (Sn or Sn-flux), pour at about 360–380 °C into a preheated (~230–260 °C) shell and chill from the back for a sound, well-bonded lining.
B23 Grade 8 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 | 4.5 – 5.5 | 5 |
| Sbantimony — forms hard SbSn/Sb phase | 14 – 16 | 15 |
| Asarsenic — grain refiner, raises hot hardness | 0.3 – 0.6 | 0.45 |
| Cu | ≤ 0.5 | — |
| Fe | ≤ 0.1 | — |
| Bi | ≤ 0.1 | — |
| Al | ≤ 0.01 | — |
| Zn | ≤ 0.01 | — |
| Pbbalance, ~79–80 % | balance | — |
What surface finishes work on B23 Grade 8?
Finish is the machined/scraped bore itself; no anodizing or plating — protect stock from moisture and handle as a lead-containing material (RoHS/REACH restrictions apply).
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy B23 Grade 8 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- L53565
How much does B23 Grade 8 cost?
B23 Grade 8 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.
B23 Grade 8 — frequently asked
What is B23 Grade 8 used for?
B23 Grade 8 is typically used for general purpose plain bearings, pump and motor bushings, low-speed shaft bearings and bearing re-babbitting/repair. In short: economical lead babbitt; low-load bearing lining; very free-machining bore.
What is the yield strength of B23 Grade 8?
B23 Grade 8 has a typical yield strength of 26 MPa (3.77 ksi) and a tensile strength of 55 MPa (7.98 ksi) — weaker than 55% of solder & low-melting alloy grades. Strength varies by condition: see the 2 listed tempers.
Is B23 Grade 8 easy to machine?
Yes — machinability is rated excellent (90/100, better than 95% of solder & low-melting alloy grades). Bores and scrapes very easily with sharp, high-rake tools and generous clearance; use light cuts, flood coolant to avoid smearing, and capture lead-bearing swarf per occupational hygiene rules.
Can B23 Grade 8 be welded?
Not readily — weldability is rated poor (20/100). Not arc-weldable; repair by torch build-up with matching babbitt filler or by stripping and re-pouring the lining.
What surface finishes work on B23 Grade 8?
Finish is the machined/scraped bore itself; no anodizing or plating — protect stock from moisture and handle as a lead-containing material (RoHS/REACH restrictions apply).
Can B23 Grade 8 be formed, bent or molded?
Cast only — degas and skim the melt, tin the steel shell (Sn or Sn-flux), pour at about 360–380 °C into a preheated (~230–260 °C) shell and chill from the back for a sound, well-bonded lining.
What is the maximum service temperature of B23 Grade 8?
B23 Grade 8 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does B23 Grade 8 cost?
B23 Grade 8 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 B23 Standard Specification for White Metal Bearing Alloys (Babbitt Metal) — ASTM International (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Bearing alloys) — ASM International (1990)
- ASM Handbook Vol. 18 — Friction, Lubrication, and Wear Technology — ASM International (2017)
- SAE J460 / UNS L53565 designation cross-reference — SAE International / ASTM-SAE Unified Numbering System (2018)
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.