Copper Alloy C36600-M20
Finish state · default condition
UNS C36600 · ASTM B121
M20 = as hot rolled
Standard supply condition for ASTM B171 condenser and heat-exchanger tube plate; best combination of strength and drillability.
Values for the M20 condition
Other C36600 tempers and conditions
C36600 is listed in 5 conditions; see the grade overview at C36600.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Use when maximum ductility is needed for bending or when residual stress must be removed before machining. | 125 | 345 | 50 | 70 HB | 28 % IACS |
M20DefaultThis page As hot rolled | Standard supply condition for ASTM B171 condenser and heat-exchanger tube plate; best combination of strength and drillability. | 138 | 372 | 45 | 80 HB | 28 % IACS |
As hot extruded | Pick for extruded bar, rod or sections that will be machined rather than formed. | 145 | 365 | 40 | 80 HB | 28 % IACS |
Quarter hard | Light cold reduction for higher yield strength in thin plate and strip where only mild forming follows. | 275 | 420 | 25 | 110 HB | 27 % IACS |
Half hard | Highest practical strength condition for this alloy; for flat parts machined or only slightly bent. | 350 | 470 | 15 | 130 HB | 27 % IACS |
What is C36600-M20?
C36600-M20 is C36600 supplied in the M20 condition — standard supply condition for ASTM B171 condenser and heat-exchanger tube plate; best combination of strength and drillability. C36600-M20 has a yield strength of 138 MPa (20 ksi) and a tensile strength of 372 MPa (54 ksi) — weaker than 76% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 105 GPa (15.2 Msi). C36600-M20 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 885°C (1,625 °F).
Advantages
- Ductile — tolerates forming and impact — 45%, better than 91% of copper alloy grades
Limitations
- Low strength — 138 MPa (20 ksi), worse than 76% of copper alloy grades
C36600-M20 properties
Typical room-temperature values for C36600-M20; 11 are specific to this condition. Other listed values are C36600 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C36600-M20 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 885°C (1,625 °F).
Mechanical11
C36600-M20 has a yield strength of 138 MPa (20 ksi) and a tensile strength of 372 MPa (54 ksi) — weaker than 76% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 105 GPa (15.2 Msi).
Thermal6
C36600-M20 is rated for continuous service to 200°C (392 °F). It conducts heat at 123 W/m·K (71.1 BTU/hr·ft·°F), better than 70% of copper alloy grades. Thermal expansion is 20.8 µm/m·K (11.6 µin/in·°F).
Electrical3
C36600-M20 conducts electricity at 28 % IACS, better than 69% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 86% of copper alloy grades.
Sustainability4
Producing a kilogram of C36600-M20 takes about 62 MJ of energy and emits 3.8 kg of CO₂ — more than 76% of copper alloy grades. Typical recycled content is 55%.
Manufacturability7
C36600-M20's machinability is good (60/100, better than 74% of copper alloy grades); weldability fair (40/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C36600-M20
Is C36600 easy to machine?
Free-machining enough for gang-drilling tube-plate hole patterns; use sharp carbide or HSS tools, 0–5° rake, generous coolant — chips are short but stringier than C36000.
Can C36600 be welded?
Fusion welding is not recommended (lead causes hot cracking and zinc fumes); join by soldering or silver brazing, with fume extraction.
Can C36600 be formed, bent or molded?
Excellent hot working at 650–760 °C; cold forming limited by the β phase — anneal at 425–600 °C and avoid tight bend radii.
What surface finishes work on C36600?
Takes a good mechanical polish and accepts nickel/tin/chrome plating; a light acid pickle removes hot-rolling oxide, and stress-relief annealing reduces ammonia SCC risk.
C36600 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 |
|---|---|---|
| Cu | 58 – 61 | 59.5 |
| Pbmachinability addition | 0.25 – 0.7 | 0.45 |
| Fe | ≤ 0.15 | — |
| Asdezincification inhibitor | 0.02 – 0.1 | 0.05 |
| Zn | balance | — |
C36600-M20 — frequently asked
What is C36600-M20 used for?
C36600-M20 is typically used for architectural trim, valve stems and condenser hardware. In short: low-lead Muntz metal; 60/40 strength, moderate machining; strong hot workability.
What is the yield strength of C36600-M20?
C36600-M20 has a typical yield strength of 138 MPa (20 ksi) and a tensile strength of 372 MPa (54 ksi) — weaker than 76% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is C36600-M20 easy to machine?
Reasonably — machinability is rated good (60/100, better than 74% of copper alloy grades). Free-machining enough for gang-drilling tube-plate hole patterns; use sharp carbide or HSS tools, 0–5° rake, generous coolant — chips are short but stringier than C36000.
Can C36600-M20 be welded?
With care — weldability is rated fair (40/100). Fusion welding is not recommended (lead causes hot cracking and zinc fumes); join by soldering or silver brazing, with fume extraction.
What surface finishes work on C36600-M20?
Takes a good mechanical polish and accepts nickel/tin/chrome plating; a light acid pickle removes hot-rolling oxide, and stress-relief annealing reduces ammonia SCC risk.
Can C36600-M20 be formed, bent or molded?
Excellent hot working at 650–760 °C; cold forming limited by the β phase — anneal at 425–600 °C and avoid tight bend radii.
What is the maximum service temperature of C36600-M20?
C36600-M20 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 C36600-M20 and C36600-H02?
M20 is the default condition — standard supply condition for ASTM B171 condenser and heat-exchanger tube plate; best combination of strength and drillability. H02: highest practical strength condition for this alloy; for flat parts machined or only slightly bent. Yield strength is 138 MPa in M20 versus 350 MPa in H02.
Sources
- ASTM B171/B171M — Copper-Alloy Plate and Sheet for Pressure Vessels, Condensers, and Heat Exchangers — ASTM International (2018)
- ASTM B121/B121M — Leaded Brass Plate, Sheet, Strip and Rolled Bar — ASTM International (2020)
- CDA Alloy Datasheet C36500–C36800 (Leaded Muntz Metal) — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.