Copper Alloy TU2-M
Heat-treated state · default condition
GB TU2 · UNS C10200, C12200 · JIS C1020
M = thermomechanically controlled processed
Default stock condition: maximum conductivity and ductility for deep drawing, gaskets, vacuum parts, ACR tube and busbar bending.
Values for the M condition
Other TU2 tempers and conditions
TU2 is listed in 8 conditions; see the grade overview at TU2.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MDefaultThis page Thermomechanically controlled processed | Default stock condition: maximum conductivity and ductility for deep drawing, gaskets, vacuum parts, ACR tube and busbar bending. | 70 | 230 | 45 | 42 HB | 101 % IACS |
Light drawn tube | Semi-flexible drawn tube for refrigeration/medical-gas lines that must still be bent but hold shape. | 190 | 250 | 25 | 70 HB | 100 % IACS |
quarter hard, cold worked ~11 % | Light cold work for stiffer sheet/strip that still bends and forms; used for stamped terminals and shielding. | 195 | 260 | 30 | 70 HB | 100 % IACS |
half hard | Common compromise temper for bar, strip and busbar needing handling stiffness with moderate bendability. | 225 | 285 | 16 | 85 HB | 99 % IACS |
Hard drawn | Rigid drawn tube for pressure lines, waveguide and vacuum plumbing where straightness and pressure rating matter. | 275 | 315 | 10 | 95 HB | 98 % IACS |
hard drawn / hard rolled | Choose for straight rod, machined electrodes, commutator bars and busbar where strength and dimensional stability outrank formability. | 290 | 330 | 8 | 100 HB | 98 % IACS |
extra hard | Heavily cold-worked strip/rod for maximum strength copper contacts and springy clips where forming is minimal. | 320 | 355 | 5 | 105 HB | 97 % IACS |
Spring hard | Maximum cold-worked strength for conductive springs, gaskets and RF finger stock; almost no forming reserve. | 350 | 390 | 4 | 115 HB | 97 % IACS |
What is TU2-M?
TU2-M is TU2 heat treated to M — default stock condition: maximum conductivity and ductility for deep drawing, gaskets, vacuum parts, ACR tube and busbar bending. TU2-M has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 93% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi). TU2-M has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Advantages
- Conducts heat well — 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades
- High electrical conductivity — 101 % IACS, better than 98% of copper alloy grades
- Forms and bends easily — 95/100, better than 94% of copper alloy grades
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
- Ductile — tolerates forming and impact — 45%, better than 91% of copper alloy grades
Limitations
- Difficult to machine — 20/100, worse than 98% of copper alloy grades
- Low strength — 70 MPa (10.2 ksi), worse than 93% of copper alloy grades
TU2-M properties
Typical room-temperature values for TU2-M; 16 are specific to this condition. Other listed values are TU2 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
TU2-M has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Mechanical12
TU2-M has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 93% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi).
Thermal6
TU2-M is rated for continuous service to 250°C (482 °F). It conducts heat at 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
TU2-M conducts electricity at 101 % IACS, better than 98% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 68% of copper alloy grades.
Sustainability4
Producing a kilogram of TU2-M takes about 57 MJ of energy and emits 3.8 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 10%.
Manufacturability7
TU2-M's machinability is poor (20/100, worse than 98% of copper alloy grades); weldability very good (70/100); formability excellent (95/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with TU2-M
Is TU2 easy to machine?
Gummy and stringy — use sharp positive-rake tools, high speed with low feed, generous coolant, and prefer half-hard/hard temper to reduce burring.
Can TU2 be welded?
GTAW/EBW/laser and friction welding all work well; oxygen-free chemistry avoids hydrogen embrittlement, but preheat 200–500 °C and high heat input are needed because of 390 W/m·K conductivity.
Can TU2 be formed, bent or molded?
In M temper it deep-draws, spins and cold-heads readily with no intermediate cracking; interstage anneal at 375–650 °C after ~60 % reduction.
What surface finishes work on TU2?
Not anodisable — electroplate Ni/Ag/Sn or Au for contacts, or use chemical blackening/clear lacquer; takes a bright mirror polish but tarnishes without a coating.
TU2 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 |
|---|---|---|
| Ooxygen ceiling that defines the OF grade | ≤ 0 | 0 |
| P | ≤ 0 | — |
| Bi | ≤ 0 | — |
| Sb | ≤ 0 | — |
| As | ≤ 0 | — |
| Fe | ≤ 0 | — |
| Ni | ≤ 0 | — |
| Pb | ≤ 0 | — |
| Sn | ≤ 0 | — |
| S | ≤ 0 | — |
| Zn | ≤ 0 | — |
| CuCu + Ag, oxygen-free; total impurities ≤ 0.05 % | ≥ 99.95 (balance) | — |
TU2-M — frequently asked
What is TU2-M used for?
TU2-M is typically used for refrigeration tubing, bus conductors, vacuum parts and welding cable. In short: standard oxygen-free copper; weldable without embrittlement; refrigeration tube grade.
What is the yield strength of TU2-M?
TU2-M has a typical yield strength of 70 MPa (10.2 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 93% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is TU2-M easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of copper alloy grades). Gummy and stringy — use sharp positive-rake tools, high speed with low feed, generous coolant, and prefer half-hard/hard temper to reduce burring.
Can TU2-M be welded?
Yes — weldability is rated very good (70/100). GTAW/EBW/laser and friction welding all work well; oxygen-free chemistry avoids hydrogen embrittlement, but preheat 200–500 °C and high heat input are needed because of 390 W/m·K conductivity.
What surface finishes work on TU2-M?
Not anodisable — electroplate Ni/Ag/Sn or Au for contacts, or use chemical blackening/clear lacquer; takes a bright mirror polish but tarnishes without a coating.
Can TU2-M be formed, bent or molded?
In M temper it deep-draws, spins and cold-heads readily with no intermediate cracking; interstage anneal at 375–650 °C after ~60 % reduction.
What is the maximum service temperature of TU2-M?
TU2-M is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between TU2-M and TU2-H08?
M is the default condition — default stock condition: maximum conductivity and ductility for deep drawing, gaskets, vacuum parts, ACR tube and busbar bending. H08: maximum cold-worked strength for conductive springs, gaskets and RF finger stock; almost no forming reserve. Yield strength is 70 MPa in M versus 350 MPa in H08.
Sources
- ASTM B170 Oxygen-Free Electrolytic Copper — Refinery Shapes — ASTM (2019)
- ASTM B152/B152M Copper Sheet, Strip, Plate and Rolled Bar — ASTM (2019)
- ASTM B75/B68 Seamless Copper Tube — ASTM (2020)
- C10200 Oxygen-Free Copper alloy datasheet — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties of 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.