Copper Alloy C87600-SR (Stress relieved)
Heat-treated state
UNS C87600 · ASTM B584
Specify when casting-to-machining distortion or residual-stress SCC in ammonia-bearing service must be minimised.
Values for the SR condition
Other C87600 tempers and conditions
C87600 is listed in 6 conditions; see the grade overview at C87600.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SRThis page Stress relieved | Specify when casting-to-machining distortion or residual-stress SCC in ammonia-bearing service must be minimised. | 205 | 425 | 22 | 100 HB | 6.8 % IACS |
F-SANDDefault As-Cast | Default commercial condition for valve bodies, plumbing fittings and marine hardware poured in green/resin sand. | 220 | 435 | 20 | 105 HB | 6.5 % IACS |
As-Cast | For thin-walled, near-net-shape decorative or marine parts where machining allowance must be minimal. | 225 | 440 | 20 | 105 HB | 6.5 % IACS |
As-Cast | Choose for higher-volume small fittings needing tighter dimensions and a finer grain than sand casting. | 240 | 470 | 20 | 115 HB | 6.5 % IACS |
As-Cast | Use for large-diameter rings, bushings and pump/valve sleeves where a segregation-free, void-free wall is required. | 245 | 470 | 19 | 115 HB | 6.5 % IACS |
As-Cast | Pick for machined stock: dense, sound, directionally solidified bar and hollows with the best consistency. | 250 | 480 | 18 | 120 HB | 6.5 % IACS |
What is C87600-SR?
C87600-SR is C87600 heat treated to SR — specify when casting-to-machining distortion or residual-stress SCC in ammonia-bearing service must be minimised. C87600-SR has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 425 MPa (61.6 ksi) — weaker than 53% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 103 GPa (14.9 Msi). C87600-SR has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 900°C (1,652 °F). F-SAND is the default condition FabDigit quotes; SR is available on request or by drawing note.
Advantages
- Readily welded — 78/100, better than 91% of copper alloy grades
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
Limitations
- Poor heat conductor — 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades
- Low electrical conductivity — 6.8 % IACS, worse than 88% of copper alloy grades
C87600-SR properties
Typical room-temperature values for C87600-SR; 20 are specific to this condition. Other listed values are C87600 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C87600-SR has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 900°C (1,652 °F).
Mechanical14
C87600-SR has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 425 MPa (61.6 ksi) — weaker than 53% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C87600-SR is rated for continuous service to 200°C (392 °F). It conducts heat at 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).
Electrical3
C87600-SR conducts electricity at 6.8 % IACS, worse than 88% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 84% of copper alloy grades.
Sustainability4
Producing a kilogram of C87600-SR takes about 50 MJ of energy and emits 3.6 kg of CO₂ — less than 89% of copper alloy grades. Typical recycled content is 75%.
Manufacturability8
C87600-SR's machinability is fair (42/100, better than 59% of copper alloy grades); weldability very good (78/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C87600-SR
Is C87600 easy to machine?
Machines like an unleaded bronze — gummy chips; use sharp positive-rake carbide, high speed, generous feed and flood coolant, expect ~40 % of free-cutting brass rates.
Can C87600 be welded?
Readily GTAW/GMAW welded and repaired with ERCuSi-A filler, low preheat (<100 °C) and low interpass temperature to avoid hot short cracking.
Can C87600 be formed, bent or molded?
Foundry alloy with excellent fluidity and short freezing range: use chills and generous risering for directional solidification, and avoid heavy section changes.
What surface finishes work on C87600?
Not anodizable; buffs to a bright gold finish, accepts chemical patina, clear lacquer, or nickel/chrome plating over a struck copper layer.
C87600 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 |
|---|---|---|
| Si | 3.5 – 5.5 | 4.5 |
| Zn | 4 – 7 | 5.5 |
| Fe | ≤ 0.2 | — |
| Mn | ≤ 0.25 | — |
| Al | ≤ 0.15 | — |
| Pbmax — low-lead potable-water alloy | ≤ 0.09 | — |
| Cu88.0 % min per ASTM B584 | ≥ 88 (balance) | — |
C87600-SR — frequently asked
What is C87600-SR used for?
C87600-SR is typically used for plumbing fittings, marine hardware, valve bodies and pump parts. In short: strongest common silicon bronze; ASTM B584 plumbing grade; lead-free pressure castings.
What is the yield strength of C87600-SR?
C87600-SR has a typical yield strength of 205 MPa (29.7 ksi) and a tensile strength of 425 MPa (61.6 ksi) — weaker than 53% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.
Is C87600-SR easy to machine?
Not especially — machinability is rated fair (42/100, better than 59% of copper alloy grades). Machines like an unleaded bronze — gummy chips; use sharp positive-rake carbide, high speed, generous feed and flood coolant, expect ~40 % of free-cutting brass rates.
Can C87600-SR be welded?
Yes — weldability is rated very good (78/100). Readily GTAW/GMAW welded and repaired with ERCuSi-A filler, low preheat (<100 °C) and low interpass temperature to avoid hot short cracking.
What surface finishes work on C87600-SR?
Not anodizable; buffs to a bright gold finish, accepts chemical patina, clear lacquer, or nickel/chrome plating over a struck copper layer.
Can C87600-SR be formed, bent or molded?
Foundry alloy with excellent fluidity and short freezing range: use chills and generous risering for directional solidification, and avoid heavy section changes.
What is the maximum service temperature of C87600-SR?
C87600-SR is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C87600 F-SAND and C87600 F-CONT?
F-SAND is the default condition — default commercial condition for valve bodies, plumbing fittings and marine hardware poured in green/resin sand. F-CONT: pick for machined stock: dense, sound, directionally solidified bar and hollows with the best consistency. Yield strength is 220 MPa in F-SAND versus 250 MPa in F-CONT.
Sources
- ASTM B584 — Copper Alloy Sand Castings for General Applications — ASTM International (2022)
- ASTM B505/B505M — Copper Alloy Continuous Castings — ASTM International (2018)
- CDA Alloy Database — C87600 silicon bronze — Copper Development Association (copper.org) (2024)
- ASM Handbook Vol.2 — Properties of Copper and Copper Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion of Copper Alloys — ASM International (2005)
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.