Solder & Low-Melting Alloy B23 Grade 8-SC
Finish state
ASTM B23 Grade 8 · UNS L53565
SC = static (gravity) cast lining on steel/bronze shell
Choose for large, thick-wall bearings and field re-babbitting where slow solidification is acceptable.
Values for the SC condition
Other B23 Grade 8 tempers and conditions
B23 Grade 8 is listed in 2 conditions; see the grade overview at B23 Grade 8.
- SC
- CHILL
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SCThis page 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 |
What is B23 Grade 8-SC?
B23 Grade 8-SC is B23 Grade 8 supplied in the SC condition — choose for large, thick-wall bearings and field re-babbitting where slow solidification is acceptable. B23 Grade 8-SC has a yield strength of 22 MPa (3.19 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 70% of solder & low-melting alloy grades. Elongation at break is 2.5% and the elastic modulus is 28 GPa (4.06 Msi). B23 Grade 8-SC 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).
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 — 2.5%, worse than 97% 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-SC properties
Typical room-temperature values for B23 Grade 8-SC; 19 are specific to this condition. Other listed values are B23 Grade 8 reference data and may not represent this condition. Bars are the position among solder & low-melting alloy grades.
Physical3
B23 Grade 8-SC 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-SC has a yield strength of 22 MPa (3.19 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 70% of solder & low-melting alloy grades. Elongation at break is 2.5% and the elastic modulus is 28 GPa (4.06 Msi).
Thermal6
B23 Grade 8-SC is rated for continuous service to 115°C (239 °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-SC 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-SC 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-SC's machinability is excellent (90/100, better than 95% of solder & low-melting alloy grades); weldability poor (20/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with B23 Grade 8-SC
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.
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).
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 | — |
B23 Grade 8-SC — frequently asked
What is B23 Grade 8-SC used for?
B23 Grade 8-SC 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-SC?
B23 Grade 8-SC has a typical yield strength of 22 MPa (3.19 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 70% of solder & low-melting alloy grades. Strength varies by condition: see the 2 listed tempers.
Is B23 Grade 8-SC 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-SC 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-SC?
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-SC 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-SC?
B23 Grade 8-SC is rated for continuous use to about 115°C (239 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.